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Conserved domains on  [gi|17540172|ref|NP_501400|]
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G-protein coupled receptors family 3 profile domain-containing protein [Caenorhabditis elegans]

Protein Classification

Graphical summary

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List of domain hits

Name Accession Description Interval E-value
7tm_classC_mGluR-like cd13953
metabotropic glutamate receptor-like class C family of seven-transmembrane G protein-coupled ...
1072-1266 1.20e-54

metabotropic glutamate receptor-like class C family of seven-transmembrane G protein-coupled receptors superfamily; The class C GPCRs consist of glutamate receptors (mGluR1-8), the extracellular calcium-sensing receptors (caSR), the gamma-amino-butyric acid type B receptors (GABA-B), the vomeronasal type-2 pheromone receptors (V2R), the type 1 taste receptors (TAS1R), and the promiscuous L-alpha-amino acid receptor (GPRC6A), as well as several orphan receptors. Structurally, these receptors are typically composed of a large extracellular domain containing a Venus flytrap module which possesses the orthosteric agonist-binding site, a cysteine-rich domain (CRD) with the exception of GABA-B receptors, and the seven-transmembrane domains responsible for G protein activation. Moreover, the Venus flytrap module shows high structural homology with bacterial periplasmic amino acid-binding proteins, which serve as primary receptors in transport of a variety of soluble substrates such as amino acids and polysaccharides, among many others. The class C GPCRs exist as either homo- or heterodimers, which are essential for their function. The GABA-B1 and GABA-B2 receptors form a heterodimer via interactions between the N-terminal Venus flytrap modules and the C-terminal coiled-coiled domains. On the other hand, heterodimeric CaSRs and Tas1Rs and homodimeric mGluRs utilize Venus flytrap interactions and intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD), which can also acts as a molecular link to mediate the signal between the Venus flytrap and the 7TMs. Furthermore, members of the class C GPCRs bind a variety of endogenous ligands, ranging from amino acids, ions, to pheromones and sugar molecules, and play important roles in many physiological processes such as synaptic transmission, calcium homeostasis, and the sensation of sweet and umami tastes.


:

Pssm-ID: 320091 [Multi-domain]  Cd Length: 251  Bit Score: 191.30  E-value: 1.20e-54
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGF---GTAIHISFWNYWLLLFFIVGVQIALSIS 1148
Cdd:cd13953   52 FLLAFLFLLPPSDVLCGLRRFLFGLSFTLVFSTLLVKTNRIYRIFKSGLrssLRPKLLSNKSQLLLVLFLLLVQVAILIV 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1149 WF-LEPFMSTIGVIDTN-VQRMMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWVAWI 1226
Cdd:cd13953  132 WLiLDPPKVEKVIDSDNkVVELCCSTGNIGLILSLVYNILLLLICTYLAFKTRKLPDNFNEARYIGFSSLLSLVIWIAFI 211
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|
gi 17540172 1227 TLYLVLDHEFRDTVIVVELVACATILLGFLFGPKIYILLS 1266
Cdd:cd13953  212 PTYFTTSGPYRDAILSFGLLLNATVLLLCLFLPKIYIILF 251
PBP1_GPCR_family_C-like cd06350
ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory ...
57-354 8.37e-53

ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory transmission on the cellular surface through initial binding of glutamate; categorized into ionotropic glutamate receptors (iGluRs) and metabotropic glutamate receptors (m; Ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory transmission on the cellular surface through initial binding of glutamate and are categorized into ionotropic glutamate receptors (iGluRs) and metabotropic glutamate receptors (mGluRs). The metabotropic glutamate receptors (mGluR) are key receptors in the modulation of excitatory synaptic transmission in the central nervous system. The mGluRs are coupled to G proteins and are thus distinct from the iGluRs which internally contain ligand-gated ion channels. The mGluR structure is divided into three regions: the extracellular region, the seven-spanning transmembrane region and the cytoplasmic region. The extracellular region is further divided into the ligand-binding domain (LBD) and the cysteine-rich domain. The LBD has sequence similarity to the LIVBP, which is a bacterial periplasmic protein (PBP), as well as to the extracellular region of both iGluR and the gamma-aminobutyric acid (GABA)b receptor. iGluRs are divided into three main subtypes based on pharmacological profile: NMDA, AMPA, and kainate receptors. All family C GPCRs have a large extracellular N terminus that contain a domain with homology to bacterial periplasmic amino acid-binding proteins.


:

Pssm-ID: 380573  Cd Length: 350  Bit Score: 189.43  E-value: 8.37e-53
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172   57 IGGSFPLHQDD------CTTLRPDTVQEIVAIQWALTHWNQK-DENGDCKLGLYAGDTCSRSAESLSQSLRFLDSVGYHE 129
Cdd:cd06350    2 IGGLFPVHYRDdadfccCGILNPRGVQLVEAMIYAIEEINNDsSLLPNVTLGYDIRDTCSSSSVALESSLEFLLDNGIKL 81
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  130 PKE-CRTETPGAKLLGLIAPKDYESSMSLGKFLSVSAIPVAAYSSESVNALTELDVENTIATSPTIGVYVEALIRLINQM 208
Cdd:cd06350   82 LANsNGQNIGPPNIVAVIGAASSSVSIAVANLLGLFKIPQISYASTSPELSDKIRYPYFLRTVPSDTLQAKAIADLLKHF 161
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  209 RSNLVTVV--DDGAQNPVVKKVISYLRDADIFVSESIPI-------DHPFLAQALEDSDSSIVV----SVLNKQQLLKTV 275
Cdd:cd06350  162 NWNYVSTVysDDDYGRSGIEAFEREAKERGICIAQTIVIpenstedEIKRIIDKLKSSPNAKVVvlflTESDARELLKEA 241
                        250       260       270       280       290       300       310
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 17540172  276 KHPSIyaMSKMWISIPTEGEALDESEqlelLHKDAKLEVVSLQPKYKELPQFRDYFirvlrnnfknyqllTSYIEQVYN 354
Cdd:cd06350  242 KRRNL--TGFTWIGSDGWGDSLVILE----GYEDVLGGAIGVVPRSKEIPGFDDYL--------------KSYAPYVID 300
PBP1_GPCR_family_C-like cd06350
ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory ...
532-809 2.81e-49

ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory transmission on the cellular surface through initial binding of glutamate; categorized into ionotropic glutamate receptors (iGluRs) and metabotropic glutamate receptors (m; Ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory transmission on the cellular surface through initial binding of glutamate and are categorized into ionotropic glutamate receptors (iGluRs) and metabotropic glutamate receptors (mGluRs). The metabotropic glutamate receptors (mGluR) are key receptors in the modulation of excitatory synaptic transmission in the central nervous system. The mGluRs are coupled to G proteins and are thus distinct from the iGluRs which internally contain ligand-gated ion channels. The mGluR structure is divided into three regions: the extracellular region, the seven-spanning transmembrane region and the cytoplasmic region. The extracellular region is further divided into the ligand-binding domain (LBD) and the cysteine-rich domain. The LBD has sequence similarity to the LIVBP, which is a bacterial periplasmic protein (PBP), as well as to the extracellular region of both iGluR and the gamma-aminobutyric acid (GABA)b receptor. iGluRs are divided into three main subtypes based on pharmacological profile: NMDA, AMPA, and kainate receptors. All family C GPCRs have a large extracellular N terminus that contain a domain with homology to bacterial periplasmic amino acid-binding proteins.


:

Pssm-ID: 380573  Cd Length: 350  Bit Score: 179.03  E-value: 2.81e-49
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  532 YLVGLFDLHSGQT-----CQSMAHTDISLPMAFVHTVWTFKQRFpqlGLLKDLDFGALLIDSCSSGKQAIESVVRSETQC 606
Cdd:cd06350    1 IIGGLFPVHYRDDadfccCGILNPRGVQLVEAMIYAIEEINNDS---SLLPNVTLGYDIRDTCSSSSVALESSLEFLLDN 77
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  607 FRFNQAG-RNITIVPKSVFGYASALHGD-SQESLKGYFSSGDTDASLVSVDSE---HSALQRSFTALPSSRNQALALLKL 681
Cdd:cd06350   78 GIKLLANsNGQNIGPPNIVAVIGAASSSvSIAVANLLGLFKIPQISYASTSPElsdKIRYPYFLRTVPSDTLQAKAIADL 157
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  682 LNRMQWQFVTAALSEQDpESLSLFRAFERLALDRGVCLAEVLNI--------GGSRLDNIRSTTN--VTIVFSTARDAAD 751
Cdd:cd06350  158 LKHFNWNYVSTVYSDDD-YGRSGIEAFEREAKERGICIAQTIVIpenstedeIKRIIDKLKSSPNakVVVLFLTESDARE 236
                        250       260       270       280       290       300
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 17540172  752 YLIASKIRGNhVNVMMGEAHDWYLhAPNNKELFP----GTVSVQPRNILYGDFREWLETTTP 809
Cdd:cd06350  237 LLKEAKRRNL-TGFTWIGSDGWGD-SLVILEGYEdvlgGAIGVVPRSKEIPGFDDYLKSYAP 296
 
Name Accession Description Interval E-value
7tm_classC_mGluR-like cd13953
metabotropic glutamate receptor-like class C family of seven-transmembrane G protein-coupled ...
1072-1266 1.20e-54

metabotropic glutamate receptor-like class C family of seven-transmembrane G protein-coupled receptors superfamily; The class C GPCRs consist of glutamate receptors (mGluR1-8), the extracellular calcium-sensing receptors (caSR), the gamma-amino-butyric acid type B receptors (GABA-B), the vomeronasal type-2 pheromone receptors (V2R), the type 1 taste receptors (TAS1R), and the promiscuous L-alpha-amino acid receptor (GPRC6A), as well as several orphan receptors. Structurally, these receptors are typically composed of a large extracellular domain containing a Venus flytrap module which possesses the orthosteric agonist-binding site, a cysteine-rich domain (CRD) with the exception of GABA-B receptors, and the seven-transmembrane domains responsible for G protein activation. Moreover, the Venus flytrap module shows high structural homology with bacterial periplasmic amino acid-binding proteins, which serve as primary receptors in transport of a variety of soluble substrates such as amino acids and polysaccharides, among many others. The class C GPCRs exist as either homo- or heterodimers, which are essential for their function. The GABA-B1 and GABA-B2 receptors form a heterodimer via interactions between the N-terminal Venus flytrap modules and the C-terminal coiled-coiled domains. On the other hand, heterodimeric CaSRs and Tas1Rs and homodimeric mGluRs utilize Venus flytrap interactions and intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD), which can also acts as a molecular link to mediate the signal between the Venus flytrap and the 7TMs. Furthermore, members of the class C GPCRs bind a variety of endogenous ligands, ranging from amino acids, ions, to pheromones and sugar molecules, and play important roles in many physiological processes such as synaptic transmission, calcium homeostasis, and the sensation of sweet and umami tastes.


Pssm-ID: 320091 [Multi-domain]  Cd Length: 251  Bit Score: 191.30  E-value: 1.20e-54
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGF---GTAIHISFWNYWLLLFFIVGVQIALSIS 1148
Cdd:cd13953   52 FLLAFLFLLPPSDVLCGLRRFLFGLSFTLVFSTLLVKTNRIYRIFKSGLrssLRPKLLSNKSQLLLVLFLLLVQVAILIV 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1149 WF-LEPFMSTIGVIDTN-VQRMMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWVAWI 1226
Cdd:cd13953  132 WLiLDPPKVEKVIDSDNkVVELCCSTGNIGLILSLVYNILLLLICTYLAFKTRKLPDNFNEARYIGFSSLLSLVIWIAFI 211
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|
gi 17540172 1227 TLYLVLDHEFRDTVIVVELVACATILLGFLFGPKIYILLS 1266
Cdd:cd13953  212 PTYFTTSGPYRDAILSFGLLLNATVLLLCLFLPKIYIILF 251
PBP1_GPCR_family_C-like cd06350
ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory ...
57-354 8.37e-53

ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory transmission on the cellular surface through initial binding of glutamate; categorized into ionotropic glutamate receptors (iGluRs) and metabotropic glutamate receptors (m; Ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory transmission on the cellular surface through initial binding of glutamate and are categorized into ionotropic glutamate receptors (iGluRs) and metabotropic glutamate receptors (mGluRs). The metabotropic glutamate receptors (mGluR) are key receptors in the modulation of excitatory synaptic transmission in the central nervous system. The mGluRs are coupled to G proteins and are thus distinct from the iGluRs which internally contain ligand-gated ion channels. The mGluR structure is divided into three regions: the extracellular region, the seven-spanning transmembrane region and the cytoplasmic region. The extracellular region is further divided into the ligand-binding domain (LBD) and the cysteine-rich domain. The LBD has sequence similarity to the LIVBP, which is a bacterial periplasmic protein (PBP), as well as to the extracellular region of both iGluR and the gamma-aminobutyric acid (GABA)b receptor. iGluRs are divided into three main subtypes based on pharmacological profile: NMDA, AMPA, and kainate receptors. All family C GPCRs have a large extracellular N terminus that contain a domain with homology to bacterial periplasmic amino acid-binding proteins.


Pssm-ID: 380573  Cd Length: 350  Bit Score: 189.43  E-value: 8.37e-53
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172   57 IGGSFPLHQDD------CTTLRPDTVQEIVAIQWALTHWNQK-DENGDCKLGLYAGDTCSRSAESLSQSLRFLDSVGYHE 129
Cdd:cd06350    2 IGGLFPVHYRDdadfccCGILNPRGVQLVEAMIYAIEEINNDsSLLPNVTLGYDIRDTCSSSSVALESSLEFLLDNGIKL 81
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  130 PKE-CRTETPGAKLLGLIAPKDYESSMSLGKFLSVSAIPVAAYSSESVNALTELDVENTIATSPTIGVYVEALIRLINQM 208
Cdd:cd06350   82 LANsNGQNIGPPNIVAVIGAASSSVSIAVANLLGLFKIPQISYASTSPELSDKIRYPYFLRTVPSDTLQAKAIADLLKHF 161
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  209 RSNLVTVV--DDGAQNPVVKKVISYLRDADIFVSESIPI-------DHPFLAQALEDSDSSIVV----SVLNKQQLLKTV 275
Cdd:cd06350  162 NWNYVSTVysDDDYGRSGIEAFEREAKERGICIAQTIVIpenstedEIKRIIDKLKSSPNAKVVvlflTESDARELLKEA 241
                        250       260       270       280       290       300       310
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 17540172  276 KHPSIyaMSKMWISIPTEGEALDESEqlelLHKDAKLEVVSLQPKYKELPQFRDYFirvlrnnfknyqllTSYIEQVYN 354
Cdd:cd06350  242 KRRNL--TGFTWIGSDGWGDSLVILE----GYEDVLGGAIGVVPRSKEIPGFDDYL--------------KSYAPYVID 300
PBP1_GPCR_family_C-like cd06350
ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory ...
532-809 2.81e-49

ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory transmission on the cellular surface through initial binding of glutamate; categorized into ionotropic glutamate receptors (iGluRs) and metabotropic glutamate receptors (m; Ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory transmission on the cellular surface through initial binding of glutamate and are categorized into ionotropic glutamate receptors (iGluRs) and metabotropic glutamate receptors (mGluRs). The metabotropic glutamate receptors (mGluR) are key receptors in the modulation of excitatory synaptic transmission in the central nervous system. The mGluRs are coupled to G proteins and are thus distinct from the iGluRs which internally contain ligand-gated ion channels. The mGluR structure is divided into three regions: the extracellular region, the seven-spanning transmembrane region and the cytoplasmic region. The extracellular region is further divided into the ligand-binding domain (LBD) and the cysteine-rich domain. The LBD has sequence similarity to the LIVBP, which is a bacterial periplasmic protein (PBP), as well as to the extracellular region of both iGluR and the gamma-aminobutyric acid (GABA)b receptor. iGluRs are divided into three main subtypes based on pharmacological profile: NMDA, AMPA, and kainate receptors. All family C GPCRs have a large extracellular N terminus that contain a domain with homology to bacterial periplasmic amino acid-binding proteins.


Pssm-ID: 380573  Cd Length: 350  Bit Score: 179.03  E-value: 2.81e-49
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  532 YLVGLFDLHSGQT-----CQSMAHTDISLPMAFVHTVWTFKQRFpqlGLLKDLDFGALLIDSCSSGKQAIESVVRSETQC 606
Cdd:cd06350    1 IIGGLFPVHYRDDadfccCGILNPRGVQLVEAMIYAIEEINNDS---SLLPNVTLGYDIRDTCSSSSVALESSLEFLLDN 77
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  607 FRFNQAG-RNITIVPKSVFGYASALHGD-SQESLKGYFSSGDTDASLVSVDSE---HSALQRSFTALPSSRNQALALLKL 681
Cdd:cd06350   78 GIKLLANsNGQNIGPPNIVAVIGAASSSvSIAVANLLGLFKIPQISYASTSPElsdKIRYPYFLRTVPSDTLQAKAIADL 157
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  682 LNRMQWQFVTAALSEQDpESLSLFRAFERLALDRGVCLAEVLNI--------GGSRLDNIRSTTN--VTIVFSTARDAAD 751
Cdd:cd06350  158 LKHFNWNYVSTVYSDDD-YGRSGIEAFEREAKERGICIAQTIVIpenstedeIKRIIDKLKSSPNakVVVLFLTESDARE 236
                        250       260       270       280       290       300
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 17540172  752 YLIASKIRGNhVNVMMGEAHDWYLhAPNNKELFP----GTVSVQPRNILYGDFREWLETTTP 809
Cdd:cd06350  237 LLKEAKRRNL-TGFTWIGSDGWGD-SLVILEGYEdvlgGAIGVVPRSKEIPGFDDYLKSYAP 296
7tm_3 pfam00003
7 transmembrane sweet-taste receptor of 3 GCPR; This is a domain of seven transmembrane ...
1072-1260 5.99e-34

7 transmembrane sweet-taste receptor of 3 GCPR; This is a domain of seven transmembrane regions that forms the C-terminus of some subclass 3 G-coupled-protein receptors. It is often associated with a downstream cysteine-rich linker domain, NCD3G pfam07562, which is the human sweet-taste receptor, and the N-terminal domain, ANF_receptor pfam01094. The seven TM regions assemble in such a way as to produce a docking pocket into which such molecules as cyclamate and lactisole have been found to bind and consequently confer the taste of sweetness.


Pssm-ID: 459626 [Multi-domain]  Cd Length: 247  Bit Score: 131.24  E-value: 5.99e-34
                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172   1072 YSTAFFFVFDPTdSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFGTaihISFWNYWLLLFFIVGVQIALSISWFL 1151
Cdd:pfam00003   57 FLLAFLFIGKPT-VTCALRRFLFGVGFTLCFSCLLAKTFRLVLIFRRRKPG---PRGWQLLLLALGLLLVQVIILTEWLI 132
                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172   1152 EPFMSTIGVIDTNVQRMMCTMGKVEFVVSNF--YVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWVAWITLY 1229
Cdd:pfam00003  133 DPPFPEKDNLSEGKIILECEGSTSIAFLDFVlaYVGLLLLAGFLLAFKTRKLPDNFNEAKFITFSMLLSVLIWVAFIPMY 212
                          170       180       190
                   ....*....|....*....|....*....|....*
gi 17540172   1230 LVLDHEF----RDTVIVVELVACATILLGFLFGPK 1260
Cdd:pfam00003  213 LYGNKGKgtwdPVALAIFAILASGWVLLGLYFIPK 247
ANF_receptor pfam01094
Receptor family ligand binding region; This family includes extracellular ligand binding ...
574-803 3.16e-08

Receptor family ligand binding region; This family includes extracellular ligand binding domains of a wide range of receptors. This family also includes the bacterial amino acid binding proteins of known structure.


Pssm-ID: 460062 [Multi-domain]  Cd Length: 347  Bit Score: 57.40  E-value: 3.16e-08
                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172    574 GLLKDLDFGALLIDSCSSGKQAIEsvvrsetQCFRFNQAGrnitivPKSVFG-----YASALHGDSQESLKGYFSSGDTD 648
Cdd:pfam01094   18 GLLPGTKLEYIILDTCCDPSLALA-------AALDLLKGE------VVAIIGpscssVASAVASLANEWKVPLISYGSTS 84
                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172    649 ASLvsvdsehSALQRS---FTALPSSRNQALALLKLLNRMQWQFVtAALSEQDPESLSLFRAFERLALDRGVCLAEVLNI 725
Cdd:pfam01094   85 PAL-------SDLNRYptfLRTTPSDTSQADAIVDILKHFGWKRV-ALIYSDDDYGESGLQALEDALRERGIRVAYKAVI 156
                          170       180       190       200       210       220       230       240
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172    726 GGSRLDN---------IRSTTNVTIVFSTARDAADYLIASKIRGnhvnvMMGEAHDWYL----------HAPNNKELFPG 786
Cdd:pfam01094  157 PPAQDDDeiarkllkeVKSRARVIVVCCSSETARRLLKAARELG-----MMGEGYVWIAtdglttslviLNPSTLEAAGG 231
                          250       260
                   ....*....|....*....|
gi 17540172    787 TVSVQ---PRNILYGDFREW 803
Cdd:pfam01094  232 VLGFRlhpPDSPEFSEFFWE 251
ANF_receptor pfam01094
Receptor family ligand binding region; This family includes extracellular ligand binding ...
81-354 3.20e-03

Receptor family ligand binding region; This family includes extracellular ligand binding domains of a wide range of receptors. This family also includes the bacterial amino acid binding proteins of known structure.


Pssm-ID: 460062 [Multi-domain]  Cd Length: 347  Bit Score: 41.60  E-value: 3.20e-03
                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172     81 AIQWALTHWNQKDE-NGDCKLGLYAGDTCSRSAESLSQSLRFLDsvgyhepkecrtetpgAKLLGLIAPKDYESSMSLGK 159
Cdd:pfam01094    5 AVRLAVEDINADPGlLPGTKLEYIILDTCCDPSLALAAALDLLK----------------GEVVAIIGPSCSSVASAVAS 68
                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172    160 FLSVSAIPVAAYSSESvNALTELDVENTIA-TSPTIGVYVEALIRLINQMRSNLVTVV----DDGaqNPVVKKVISYLRD 234
Cdd:pfam01094   69 LANEWKVPLISYGSTS-PALSDLNRYPTFLrTTPSDTSQADAIVDILKHFGWKRVALIysddDYG--ESGLQALEDALRE 145
                          170       180       190       200       210       220       230       240
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172    235 ADIFV--SESIP--IDHPFLAQALE---DSDSSIVV---SVLNKQQLLKTVKHPSIYAMSKMWISIPTEGEALDESEQLE 304
Cdd:pfam01094  146 RGIRVayKAVIPpaQDDDEIARKLLkevKSRARVIVvccSSETARRLLKAARELGMMGEGYVWIATDGLTTSLVILNPST 225
                          250       260       270       280       290
                   ....*....|....*....|....*....|....*....|....*....|.
gi 17540172    305 LLHKDAKLEVVSLQPKYKELPQFRDYFIRVLRNNFKNYQLLT-SYIEQVYN 354
Cdd:pfam01094  226 LEAAGGVLGFRLHPPDSPEFSEFFWEKLSDEKELYENLGGLPvSYGALAYD 276
 
Name Accession Description Interval E-value
7tm_classC_mGluR-like cd13953
metabotropic glutamate receptor-like class C family of seven-transmembrane G protein-coupled ...
1072-1266 1.20e-54

metabotropic glutamate receptor-like class C family of seven-transmembrane G protein-coupled receptors superfamily; The class C GPCRs consist of glutamate receptors (mGluR1-8), the extracellular calcium-sensing receptors (caSR), the gamma-amino-butyric acid type B receptors (GABA-B), the vomeronasal type-2 pheromone receptors (V2R), the type 1 taste receptors (TAS1R), and the promiscuous L-alpha-amino acid receptor (GPRC6A), as well as several orphan receptors. Structurally, these receptors are typically composed of a large extracellular domain containing a Venus flytrap module which possesses the orthosteric agonist-binding site, a cysteine-rich domain (CRD) with the exception of GABA-B receptors, and the seven-transmembrane domains responsible for G protein activation. Moreover, the Venus flytrap module shows high structural homology with bacterial periplasmic amino acid-binding proteins, which serve as primary receptors in transport of a variety of soluble substrates such as amino acids and polysaccharides, among many others. The class C GPCRs exist as either homo- or heterodimers, which are essential for their function. The GABA-B1 and GABA-B2 receptors form a heterodimer via interactions between the N-terminal Venus flytrap modules and the C-terminal coiled-coiled domains. On the other hand, heterodimeric CaSRs and Tas1Rs and homodimeric mGluRs utilize Venus flytrap interactions and intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD), which can also acts as a molecular link to mediate the signal between the Venus flytrap and the 7TMs. Furthermore, members of the class C GPCRs bind a variety of endogenous ligands, ranging from amino acids, ions, to pheromones and sugar molecules, and play important roles in many physiological processes such as synaptic transmission, calcium homeostasis, and the sensation of sweet and umami tastes.


Pssm-ID: 320091 [Multi-domain]  Cd Length: 251  Bit Score: 191.30  E-value: 1.20e-54
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGF---GTAIHISFWNYWLLLFFIVGVQIALSIS 1148
Cdd:cd13953   52 FLLAFLFLLPPSDVLCGLRRFLFGLSFTLVFSTLLVKTNRIYRIFKSGLrssLRPKLLSNKSQLLLVLFLLLVQVAILIV 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1149 WF-LEPFMSTIGVIDTN-VQRMMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWVAWI 1226
Cdd:cd13953  132 WLiLDPPKVEKVIDSDNkVVELCCSTGNIGLILSLVYNILLLLICTYLAFKTRKLPDNFNEARYIGFSSLLSLVIWIAFI 211
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|
gi 17540172 1227 TLYLVLDHEFRDTVIVVELVACATILLGFLFGPKIYILLS 1266
Cdd:cd13953  212 PTYFTTSGPYRDAILSFGLLLNATVLLLCLFLPKIYIILF 251
PBP1_GPCR_family_C-like cd06350
ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory ...
57-354 8.37e-53

ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory transmission on the cellular surface through initial binding of glutamate; categorized into ionotropic glutamate receptors (iGluRs) and metabotropic glutamate receptors (m; Ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory transmission on the cellular surface through initial binding of glutamate and are categorized into ionotropic glutamate receptors (iGluRs) and metabotropic glutamate receptors (mGluRs). The metabotropic glutamate receptors (mGluR) are key receptors in the modulation of excitatory synaptic transmission in the central nervous system. The mGluRs are coupled to G proteins and are thus distinct from the iGluRs which internally contain ligand-gated ion channels. The mGluR structure is divided into three regions: the extracellular region, the seven-spanning transmembrane region and the cytoplasmic region. The extracellular region is further divided into the ligand-binding domain (LBD) and the cysteine-rich domain. The LBD has sequence similarity to the LIVBP, which is a bacterial periplasmic protein (PBP), as well as to the extracellular region of both iGluR and the gamma-aminobutyric acid (GABA)b receptor. iGluRs are divided into three main subtypes based on pharmacological profile: NMDA, AMPA, and kainate receptors. All family C GPCRs have a large extracellular N terminus that contain a domain with homology to bacterial periplasmic amino acid-binding proteins.


Pssm-ID: 380573  Cd Length: 350  Bit Score: 189.43  E-value: 8.37e-53
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172   57 IGGSFPLHQDD------CTTLRPDTVQEIVAIQWALTHWNQK-DENGDCKLGLYAGDTCSRSAESLSQSLRFLDSVGYHE 129
Cdd:cd06350    2 IGGLFPVHYRDdadfccCGILNPRGVQLVEAMIYAIEEINNDsSLLPNVTLGYDIRDTCSSSSVALESSLEFLLDNGIKL 81
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  130 PKE-CRTETPGAKLLGLIAPKDYESSMSLGKFLSVSAIPVAAYSSESVNALTELDVENTIATSPTIGVYVEALIRLINQM 208
Cdd:cd06350   82 LANsNGQNIGPPNIVAVIGAASSSVSIAVANLLGLFKIPQISYASTSPELSDKIRYPYFLRTVPSDTLQAKAIADLLKHF 161
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  209 RSNLVTVV--DDGAQNPVVKKVISYLRDADIFVSESIPI-------DHPFLAQALEDSDSSIVV----SVLNKQQLLKTV 275
Cdd:cd06350  162 NWNYVSTVysDDDYGRSGIEAFEREAKERGICIAQTIVIpenstedEIKRIIDKLKSSPNAKVVvlflTESDARELLKEA 241
                        250       260       270       280       290       300       310
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 17540172  276 KHPSIyaMSKMWISIPTEGEALDESEqlelLHKDAKLEVVSLQPKYKELPQFRDYFirvlrnnfknyqllTSYIEQVYN 354
Cdd:cd06350  242 KRRNL--TGFTWIGSDGWGDSLVILE----GYEDVLGGAIGVVPRSKEIPGFDDYL--------------KSYAPYVID 300
PBP1_GPCR_family_C-like cd06350
ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory ...
532-809 2.81e-49

ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory transmission on the cellular surface through initial binding of glutamate; categorized into ionotropic glutamate receptors (iGluRs) and metabotropic glutamate receptors (m; Ligand-binding domain of membrane-bound glutamate receptors that mediate excitatory transmission on the cellular surface through initial binding of glutamate and are categorized into ionotropic glutamate receptors (iGluRs) and metabotropic glutamate receptors (mGluRs). The metabotropic glutamate receptors (mGluR) are key receptors in the modulation of excitatory synaptic transmission in the central nervous system. The mGluRs are coupled to G proteins and are thus distinct from the iGluRs which internally contain ligand-gated ion channels. The mGluR structure is divided into three regions: the extracellular region, the seven-spanning transmembrane region and the cytoplasmic region. The extracellular region is further divided into the ligand-binding domain (LBD) and the cysteine-rich domain. The LBD has sequence similarity to the LIVBP, which is a bacterial periplasmic protein (PBP), as well as to the extracellular region of both iGluR and the gamma-aminobutyric acid (GABA)b receptor. iGluRs are divided into three main subtypes based on pharmacological profile: NMDA, AMPA, and kainate receptors. All family C GPCRs have a large extracellular N terminus that contain a domain with homology to bacterial periplasmic amino acid-binding proteins.


Pssm-ID: 380573  Cd Length: 350  Bit Score: 179.03  E-value: 2.81e-49
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  532 YLVGLFDLHSGQT-----CQSMAHTDISLPMAFVHTVWTFKQRFpqlGLLKDLDFGALLIDSCSSGKQAIESVVRSETQC 606
Cdd:cd06350    1 IIGGLFPVHYRDDadfccCGILNPRGVQLVEAMIYAIEEINNDS---SLLPNVTLGYDIRDTCSSSSVALESSLEFLLDN 77
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  607 FRFNQAG-RNITIVPKSVFGYASALHGD-SQESLKGYFSSGDTDASLVSVDSE---HSALQRSFTALPSSRNQALALLKL 681
Cdd:cd06350   78 GIKLLANsNGQNIGPPNIVAVIGAASSSvSIAVANLLGLFKIPQISYASTSPElsdKIRYPYFLRTVPSDTLQAKAIADL 157
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  682 LNRMQWQFVTAALSEQDpESLSLFRAFERLALDRGVCLAEVLNI--------GGSRLDNIRSTTN--VTIVFSTARDAAD 751
Cdd:cd06350  158 LKHFNWNYVSTVYSDDD-YGRSGIEAFEREAKERGICIAQTIVIpenstedeIKRIIDKLKSSPNakVVVLFLTESDARE 236
                        250       260       270       280       290       300
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 17540172  752 YLIASKIRGNhVNVMMGEAHDWYLhAPNNKELFP----GTVSVQPRNILYGDFREWLETTTP 809
Cdd:cd06350  237 LLKEAKRRNL-TGFTWIGSDGWGD-SLVILEGYEdvlgGAIGVVPRSKEIPGFDDYLKSYAP 296
7tm_3 pfam00003
7 transmembrane sweet-taste receptor of 3 GCPR; This is a domain of seven transmembrane ...
1072-1260 5.99e-34

7 transmembrane sweet-taste receptor of 3 GCPR; This is a domain of seven transmembrane regions that forms the C-terminus of some subclass 3 G-coupled-protein receptors. It is often associated with a downstream cysteine-rich linker domain, NCD3G pfam07562, which is the human sweet-taste receptor, and the N-terminal domain, ANF_receptor pfam01094. The seven TM regions assemble in such a way as to produce a docking pocket into which such molecules as cyclamate and lactisole have been found to bind and consequently confer the taste of sweetness.


Pssm-ID: 459626 [Multi-domain]  Cd Length: 247  Bit Score: 131.24  E-value: 5.99e-34
                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172   1072 YSTAFFFVFDPTdSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFGTaihISFWNYWLLLFFIVGVQIALSISWFL 1151
Cdd:pfam00003   57 FLLAFLFIGKPT-VTCALRRFLFGVGFTLCFSCLLAKTFRLVLIFRRRKPG---PRGWQLLLLALGLLLVQVIILTEWLI 132
                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172   1152 EPFMSTIGVIDTNVQRMMCTMGKVEFVVSNF--YVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWVAWITLY 1229
Cdd:pfam00003  133 DPPFPEKDNLSEGKIILECEGSTSIAFLDFVlaYVGLLLLAGFLLAFKTRKLPDNFNEAKFITFSMLLSVLIWVAFIPMY 212
                          170       180       190
                   ....*....|....*....|....*....|....*
gi 17540172   1230 LVLDHEF----RDTVIVVELVACATILLGFLFGPK 1260
Cdd:pfam00003  213 LYGNKGKgtwdPVALAIFAILASGWVLLGLYFIPK 247
7tmC_Boss cd15042
Bride of sevenless, member of the class C family of seven-transmembrane G protein-coupled ...
1085-1265 1.20e-16

Bride of sevenless, member of the class C family of seven-transmembrane G protein-coupled receptors; Bride of Sevenless (Boss) is a putative Drosophila melanogaster G protein-coupled receptor that functions as a glucose-responding receptor to regulate energy metabolism. Boss is expressed predominantly in the fly's fat body, a nutrient-sensing tissue functionally analogous to the mammalian liver and adipose tissues, and in photoreceptor cells. Boss, which is expressed on the surface of R8 photoreceptor cell, binds and activates the Sevenless receptor tyrosine kinase on the neighboring R7 precursor cell. Activation of Sevenless results in phosphorylation of the Sevenless, triggering a signaling transduction cascade through Ras pathway that ultimately leads to the differentiation of the R7 precursor into a fully functional R7 photoreceptor, the last of eight photoreceptors to differentiate in each ommatidium of the developing Drosophila eye. In the absence of either of Sevenless or Boss, the R7 precursor fails to differentiate as a photoreceptor and instead develops into a non-neuronal cone cell. Moreover, Boss mutants in Drosophila showed elevated food intake, but reduced stored triglyceride levels, suggesting that Boss may play a role in regulating energy homeostasis in nutrient sensing tissues. Furthermore, GPRC5B, a mammalian Boss homolog, activates obesity-associated inflammatory signaling in adipocytes, and that the GPRC5B knockout mice showed resistance to high-fat diet-induced obesity and insulin resistance.


Pssm-ID: 320170  Cd Length: 238  Bit Score: 80.93  E-value: 1.20e-16
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1085 SVCRLRVILHGLGYTICFGVMIAKATQLRNAeTLGFGTAIHISFWNYWLLLFFIVGVQIALSISWFLepfmstigvidtn 1164
Cdd:cd15042   69 SLCAVRILLTTLAFGFTFSLMLSRALFLALS-TGEGGFLSHVNGYLQSVMCLFSFGVQVAMSVQYFV------------- 134
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1165 vqrmMCTMGKVEFVVSNFYVMIL-----IFMALFI-SMLNRNIKRNYKETKWLLYSTVLCFFTWVAWITLYLVLDHEFRD 1238
Cdd:cd15042  135 ----LNHANSAVIYRGLWFIALLgydifLLIALFVlCPFIFRSQRNYREGKYFFGASIGLLVIWVIWLPCFLLMGPEWRD 210
                        170       180
                 ....*....|....*....|....*..
gi 17540172 1239 TVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15042  211 AVISFGLVATAYAILVGILVPRTYLMT 237
7tmC_mGluRs_group2_3 cd15934
metabotropic glutamate receptors in group 2 and 3, member of the class C family of ...
1070-1265 4.33e-15

metabotropic glutamate receptors in group 2 and 3, member of the class C family of seven-transmembrane G protein-coupled receptors; The metabotropic glutamate receptors (mGluRs) are homodimeric class C G-protein coupled receptors which are activated by glutamate, the major excitatory neurotransmitter of the CNS. The mGluRs are involved in regulating neuronal excitability and synaptic transmission via intracellular activation of second messenger signaling pathways. While the ionotropic glutamate receptor subtypes (AMPA, NMDA, and kainite) mediate fast excitatory postsynaptic transmission, mGluRs are known to mediate slower excitatory postsynaptic responses and to be involved in synaptic plasticity in the mammalian brain. In addition to seven-transmembrane helices, the class C GPCRs are characterized by a large N-terminal extracellular Venus flytrap-like domain, which is composed of two adjacent lobes separated by a cleft which binds an endogenous ligand. Moreover, they exist as either homo- or heterodimers, which are essential for their function. For instance, mGluRs form homodimers via interactions between the N-terminal Venus flytrap domains and the intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD). At least eight different subtypes of metabotropic receptors (mGluR1-8) have been identified and further classified into three groups based on their sequence homology, pharmacological properties, and signaling pathways. Group 1 (mGluR1 and mGluR5) receptors are predominantly located postsynaptically on neurons and are involved in long-term synaptic plasticity in the brain, including long-term potentiation (LTP) in the hippocampus and long-term depression (LTD) in the cerebellum. They are coupled to G(q/11) proteins, thereby activating phospholipase C to generate inositol-1,4,5-triphosphate (IP3) and diacyglycerol (DAG), which in turn lead to Ca2+ release and protein kinase C activation, respectively. Group I mGluR expression is shown to be strongly upregulated in animal models of epilepsy, brain injury, inflammatory, and neuropathic pain, as well as in patients with amyotrophic lateral sclerosis or multiple sclerosis. Group 2 (mGluR2 and mGluR3) and 3 (mGluR4, mGluR6, mGluR7, and mGluR8) receptors are predominantly localized presynaptically in the active region of neurotransmitter release. They are coupled to (Gi/o) proteins, which leads to inhibition of adenylate cyclase activity and cAMP formation, and consequently to a decrease in protein kinase A (PKA) activity. Ultimately, activation of these receptors leads to inhibition of neurotransmitter release such as glutamate and GABA via inhibition of Ca2+ channels and activation of K+ channels. Furthermore, while activation of Group 1 mGluRs increases NMDA (N-methyl-D-aspartate) receptor activity and risk of neurotoxicity, Group 2 and 3 mGluRs decrease NMDA receptor activity and prevent neurotoxicity.


Pssm-ID: 320600  Cd Length: 252  Bit Score: 76.50  E-value: 4.33e-15
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1070 ILYSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQL--------RNAETLGFgtaihISFWNYWLLLFFIVGV 1141
Cdd:cd15934   50 LCYLMTFVLLAKPSVITCALRRLGLGLGFSICYAALLTKTNRIsrifnsgkRSAKRPRF-----ISPKSQLVICLGLISV 124
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1142 QIALSISWF-LEPFMSTIGVIDTNVQRMMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWL---LYSTvl 1217
Cdd:cd15934  125 QLIGVLVWLvVEPPGTRIDYPRRDQVVLKCKISDSSLLISLVYNMLLIILCTVYAFKTRKIPENFNEAKFIgftMYTT-- 202
                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|
gi 17540172 1218 CFFtWVAWITLYLVL--DHEFRDTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15934  203 CII-WLAFVPIYFGTsnDFKIQTTTLCVSISLSASVALGCLFAPKVYIIL 251
7tmC_mGluR_group1 cd15285
metabotropic glutamate receptors in group 1, member of the class C family of ...
1072-1265 7.65e-15

metabotropic glutamate receptors in group 1, member of the class C family of seven-transmembrane G protein-coupled receptors; Group 1 mGluRs includes mGluR1 and mGluR5, as well as their closely related invertebrate receptors. They are homodimeric class C G-protein coupled receptors which are activated by glutamate, the major excitatory neurotransmitter of the CNS. mGluRs are involved in regulating neuronal excitability and synaptic transmission via intracellular activation of second messenger signaling pathways. While the ionotropic glutamate receptor subtypes (AMPA, NMDA, and kainite) mediate fast excitatory postsynaptic transmission, mGluRs are known to mediate slower excitatory postsynaptic responses and to be involved in synaptic plasticity in the mammalian brain. In addition to seven-transmembrane helices, the class C GPCRs are characterized by a large N-terminal extracellular Venus flytrap-like domain, which is composed of two adjacent lobes separated by a cleft which binds an endogenous ligand. Moreover, they exist as either homo- or heterodimers, which are essential for their function. For instance, mGluRs form homodimers via interactions between the N-terminal Venus flytrap domains and the intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD). At least eight different subtypes of metabotropic receptors (mGluR1-8) have been identified and further classified into three groups based on their sequence homology, pharmacological properties, and signaling pathways. Group 1 (mGluR1 and mGluR5) receptors are predominantly located postsynaptically on neurons and are involved in long-term synaptic plasticity in the brain, including long-term potentiation (LTP) in the hippocampus and long-term depression (LTD) in the cerebellum. They are coupled to G(q/11) proteins, thereby activating phospholipase C to generate inositol-1,4,5-triphosphate (IP3) and diacyglycerol (DAG), which in turn lead to Ca2+ release and protein kinase C activation, respectively. Group 1 mGluR expression is shown to be strongly upregulated in animal models of epilepsy, brain injury, inflammatory, and neuropathic pain, as well as in patients with amyotrophic lateral sclerosis or multiple sclerosis. Group 2 (mGluR2 and mGluR3) and 3 (mGluR4, mGluR6, mGluR7, and mGluR8) receptors are predominantly localized presynaptically in the active region of neurotransmitter release. They are coupled to G(i/o) proteins, which leads to inhibition of adenylate cyclase activity and cAMP formation, and consequently to a decrease in protein kinase A (PKA) activity. Ultimately, activation of these receptors leads to inhibition of neurotransmitter release such as glutamate and GABA via inhibition of Ca2+ channels and activation of K+ channels. Furthermore, while activation of Group 1 mGluRs increases NMDA (N-methyl-D-aspartate) receptor activity and risk of neurotoxicity, Group 2 and 3 mGluRs decrease NMDA receptor activity and prevent neurotoxicity.


Pssm-ID: 320412  Cd Length: 250  Bit Score: 75.75  E-value: 7.65e-15
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATqlRNAETLGfGT--------AIHISFWNYWLLLFFIVGVQI 1143
Cdd:cd15285   52 YASTFALLAKPSTISCYLQRILPGLSFAMIYAALVTKTN--RIARILA-GSkkkiltrkPRFMSASAQVVITGILISVEV 128
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1144 ALSISWF-LEPFMSTIGVIDTNVQRMMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWL---LYSTVLcf 1219
Cdd:cd15285  129 AIIVVMLiLEPPDATLDYPTPKRVRLICNTSTLGFVVPLGFDFLLILLCTLYAFKTRNLPENFNEAKFIgftMYTTCV-- 206
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|....*.
gi 17540172 1220 fTWVAWITLYLVLDHEFRDTVIVVELVAcaTILLGFLFGPKIYILL 1265
Cdd:cd15285  207 -IWLAFLPIYFGSDNKEITLCFSVSLSA--TVALVFLFFPKVYIIL 249
7tmC_mGluRs cd15045
metabotropic glutamate receptors, member of the class C family of seven-transmembrane G ...
1072-1265 1.52e-14

metabotropic glutamate receptors, member of the class C family of seven-transmembrane G protein-coupled receptors; The metabotropic glutamate receptors (mGluRs) are homodimeric class C G-protein coupled receptors which are activated by glutamate, the major excitatory neurotransmitter of the CNS. mGluRs are involved in regulating neuronal excitability and synaptic transmission via intracellular activation of second messenger signaling pathways. While the ionotropic glutamate receptor subtypes (AMPA, NMDA, and kainite) mediate fast excitatory postsynaptic transmission, mGluRs are known to mediate slower excitatory postsynaptic responses and to be involved in synaptic plasticity in the mammalian brain. In addition to seven-transmembrane helices, the class C GPCRs are characterized by a large N-terminal extracellular Venus flytrap-like domain, which is composed of two adjacent lobes separated by a cleft which binds an endogenous ligand. Moreover, they exist as either homo- or heterodimers, which are essential for their function. For instance, mGluRs form homodimers via interactions between the N-terminal Venus flytrap domains and the intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD). At least eight different subtypes of metabotropic receptors (mGluR1-8) have been identified and further classified into three groups based on their sequence homology, pharmacological properties, and signaling pathways. Group 1 (mGluR1 and mGluR5) receptors are predominantly located postsynaptically on neurons and are involved in long-term synaptic plasticity in the brain, including long-term potentiation (LTP) in the hippocampus and long-term depression (LTD) in the cerebellum. They are coupled to G(q/11) proteins, thereby activating phospholipase C to generate inositol-1,4,5-triphosphate (IP3) and diacyglycerol (DAG), which in turn lead to Ca2+ release and protein kinase C activation, respectively. Group I mGluR expression is shown to be strongly upregulated in animal models of epilepsy, brain injury, inflammatory, and neuropathic pain, as well as in patients with amyotrophic lateral sclerosis or multiple sclerosis. Group 2 (mGluR2 and mGluR3) and 3 (mGluR4, mGluR6, mGluR7, and mGluR8) receptors are predominantly localized presynaptically in the active region of neurotransmitter release. They are coupled to (Gi/o) proteins, which leads to inhibition of adenylate cyclase activity and cAMP formation, and consequently to a decrease in protein kinase A (PKA) activity. Ultimately, activation of these receptors leads to inhibition of neurotransmitter release such as glutamate and GABA via inhibition of Ca2+ channels and activation of K+ channels. Furthermore, while activation of Group 1 mGluRs increases NMDA (N-methyl-D-aspartate) receptor activity and risk of neurotoxicity, Group 2 and 3 mGluRs decrease NMDA receptor activity and prevent neurotoxicity.


Pssm-ID: 320173 [Multi-domain]  Cd Length: 253  Bit Score: 74.97  E-value: 1.52e-14
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFGTAIHISFWNYWLLLFF---IVGVQIALSIS 1148
Cdd:cd15045   52 YVMTFVLVAKPSTIVCGLQRFGLGLCFTVCYAAILTKTNRIARIFRLGKKSAKRPRFISPRSQLVItglLVSVQVLVLAV 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1149 WF-LEPFMSTI--GVIDTNvQRMMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWVAW 1225
Cdd:cd15045  132 WLiLSPPRATHhyPTRDKN-VLVCSSALDASYLIGLAYPILLIILCTVYAFKTRKIPEGFNEAKYIGFTMYTTCIIWLAF 210
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|..
gi 17540172 1226 ITLYLVLDH--EFRDTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15045  211 VPLYFTTASniEVRITTLSVSISLSATVQLACLFAPKVYIIL 252
7tmC_CaSR cd15282
calcium-sensing receptor, member of the class C of seven-transmembrane G protein-coupled ...
1072-1265 6.20e-14

calcium-sensing receptor, member of the class C of seven-transmembrane G protein-coupled receptors; CaSR is a widely expressed GPCR that is involved in sensing small changes in extracellular levels of calcium ion to maintain a constant level of the extracellular calcium via modulating the synthesis and secretion of calcium regulating hormones, such as parathyroid hormone (PTH), in order to regulate Ca(2+)transport into or out of the extracellular fluid via kidney, intestine, and/or bone. For instance, when Ca2+ is high, CaSR downregulates PTH synthesis and secretion, leading to an increase in renal Ca2+ excretion, a decrease in intestinal Ca2+ absorption, and a reduction in release of skeletal Ca2+. CaSR is coupled to both G(q/11)-dependent activation of phospholipase and, subsequently, intracellular calcium mobilization and protein kinase C activation as well as G(i/o)-dependent inhibition of adenylate cyclase leading to inhibition of cAMP formation. CaSR is closely related to GRPC6A (GPCR, class C, group 6, subtype A), which is an amino acid-sensing GPCR that is most potently activated by the basic amino acids L-arginine, L-lysine, and L-ornithine. These receptors contain a large extracellular Venus flytrap-like domain in the N-terminus, cysteine-rich domain (CRD), and seven-transmembrane (7TM) domain, which are characteristics of the class C GPCRs. The Venus flytrap-like domain shares strong sequence homology to bacterial periplasmic binding proteins and possess the orthosteric amino acid and calcium binding sites for members of the class C, including CaSR, GABA-B1, GPRC6A, mGlu, and TASR1 receptors.


Pssm-ID: 320409 [Multi-domain]  Cd Length: 252  Bit Score: 73.45  E-value: 6.20e-14
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFGTAIHISFWNY---WLLLFFIVGVQIALSIS 1148
Cdd:cd15282   52 FSSSLIFIGEPQDWTCRLRQPAFGISFVLCISCILVKTNRVLLVFEAKIPTSLHRKWWGLnlqFLLVFLCTFVQIVICVI 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1149 WFLE--PFMSTIGVIDTNVQRMMCTMGKVE---FVVSnfYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWV 1223
Cdd:cd15282  132 WLYTapPSSYRNHELEDEIIFITCNEGSLMalgFLIG--YTCLLAAICFFFAFKSRKLPENFNEAKFITFSMLIFFIVWI 209
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|..
gi 17540172 1224 AWITLYLVLDHEFRDTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15282  210 SFIPAYASTYGKFVSAVEVIAILASSFGLLACIFFNKVYIIL 251
7tmC_V2R_AA_sensing_receptor-like cd15044
vomeronasal type-2 pheromone receptors, amino acid-sensing receptors and closely related ...
1072-1265 1.44e-13

vomeronasal type-2 pheromone receptors, amino acid-sensing receptors and closely related proteins; member of the class C family of seven-transmembrane G protein-coupled receptors; This group is composed of vomeronasal type-2 pheromone receptors (V2Rs), a subgroup of broad-spectrum amino-acid sensing receptors including calcium-sensing receptor (CaSR) and GPRC6A, as well as their closely related proteins. Members of the V2R family of vomeronasal GPCRs are involved in detecting protein pheromones for social and sexual cues between the same species. V2Rs and G-alpha(o) protein are co-expressed in the basal layer of the vomeronasal organ (VNO), which is the sensory organ of the accessory olfactory system present in amphibians, reptiles, and non-primate mammals such as mice and rodents, but it is non-functional or absent in humans, apes, and monkeys. On the other hand, members of the V1R receptor family and G-alpha(i2) protein are co-expressed in the apical neurons of the VNO. Activation of V1R or V2R causes activation of phospholipase pathway, producing the second messengers diacylglycerol (DAG) and IP3. However, in contrast to V1Rs, V2Rs contain the long N-terminal extracellular domain, which is believed to bind pheromones. CaSR is a widely expressed GPCR that is involved in sensing small changes in extracellular levels of calcium ion to maintain a constant level of the extracellular calcium via modulating the synthesis and secretion of calcium regulating hormones, such as parathyroid hormone (PTH), in order to regulate Ca(2+)transport into or out of the extracellular fluid via kidney, intestine, and/or bone. For instance, when Ca2+ is high, CaSR downregulates PTH synthesis and secretion, leading to an increase in renal Ca2+ excretion, a decrease in intestinal Ca2+ absorption, and a reduction in release of skeletal Ca2+. GRPC6A (GPCR, class C, group 6, subtype A) is a widely expressed amino acid-sensing GPCR that is most closely related to CaSR. GPRC6A is most potently activated by the basic amino acids L-arginine, L-lysine, and L-ornithine and less potently by small aliphatic amino acids. Moreover, the receptor can be either activated or modulated by divalent cations such as Ca2+. GPRC6A is expressed in the testis, but not the ovary and specifically also binds to the osteoblast-derived hormone osteocalcin (OCN), which regulates testosterone production by the testis and male fertility independently of the hypothalamic-pituitary axis. Furthermore, GPRC6A knockout studies suggest that GRPC6A is involved in regulation of bone metabolism, male reproduction, energy homeostasis, glucose metabolism, and in activation of inflammation response, as well as prostate cancer growth and progression, among others.


Pssm-ID: 320172 [Multi-domain]  Cd Length: 251  Bit Score: 72.12  E-value: 1.44e-13
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAK------ATQLRNAETLGFGTAIHISFwnywLLLFFIVGVQIAL 1145
Cdd:cd15044   52 FSSSLFFIGEPQDWTCKLRQTMFGVSFTLCISCILTKtlkvllAFSADKPLTQKFLMCLYLPI----LIVFTCTGIQVVI 127
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1146 SISW-FLEPFMSTIGVIDTNVQRMM-CTMGKVEFVVSNF-YVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTW 1222
Cdd:cd15044  128 CTVWlIFAPPTVEVNVSPLPRVIILeCNEGSILAFGTMLgYIAFLAFLCFLFAFKARKLPDNYNEAKFITFGMLVFFIVW 207
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|...
gi 17540172 1223 VAWITLYLVLDHEFRDTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15044  208 ISFVPAYLSTKGKFVVAVEIIAILASSYGLLGCIFLPKCYVIL 250
7tmC_GABA-B-like cd15047
gamma-aminobutyric acid type B receptor and related proteins, member of the class C family of ...
1072-1264 4.91e-13

gamma-aminobutyric acid type B receptor and related proteins, member of the class C family of seven-transmembrane G protein-coupled receptors; The type B receptor for gamma-aminobutyric acid, GABA-B, is activated by its endogenous ligand GABA, the principal inhibitory neurotransmitter. The functional GABA-B receptor is an obligatory heterodimer composed of two related subunits, GABA-B1, which is primarily involved in GABA ligand binding, and GABA-B2, which is responsible for both G-protein coupling and trafficking of the heterodimer to the plasma membrane. Activation of GABA-B couples to G(i/o)-type G proteins, which in turn modulate three major downstream effectors: adenylate cyclase, voltage-sensitive Ca2+ channels, and inwardly-rectifying K+ channels. Consequently, GABA-B receptor produces slow and sustained inhibitory responses by decreased neurotransmitter release via inhibition of Ca2+ channels and by postsynaptic hyperpolarization via the activation of K+ channels through the G-protein beta-gamma dimer. The GABA-B is expressed in both pre- and postsynaptic sites of glutamatergic and GABAergic neurons in the brain where it regulates synaptic activity. Thus, the GABA-B receptor agonist, baclofen, is used to treat muscle tightness and cramping caused by spasticity in multiple sclerosis patients. Moreover, GABA-B antagonists improves cognitive performance in mammals, while GABA-B agonists suppress cognitive behavior. In most of the class C family members, the extracellular Venus-flytrap domain in the N-terminus is connected to the seven-transmembrane (7TM) via a cysteine-rich domain (CRD). However, in the GABA-B receptor, the CRD is absent in both subunits and the Venus-flytrap ligand-binding domain is directly connected to the 7TM via a 10-15 amino acids linker, suggesting that GABA-B receptor may utilize a different activation mechanism. Also included in this group are orphan receptors, GPR156 and GPR158, which are closely related to the GABA-B receptor family.


Pssm-ID: 320175  Cd Length: 263  Bit Score: 70.67  E-value: 4.91e-13
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFD---PTDSVCRLRVILHGLGYTICFGVMIAK---------ATQLRNaetlgfgtaIHISFWNYWLLLFFIV 1139
Cdd:cd15047   52 YISVILFGLDdskPSSFLCTARPWLLSIGFTLVFGALFAKtwriyriftNKKLKR---------IVIKDKQLLKIVGILL 122
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1140 GVQIALSISWF----LEPFMSTI-------GVIDTNVQRMMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKR-NYKE 1207
Cdd:cd15047  123 LIDIIILILWTivdpLKPTRVLVlseisddVKYEYVVHCCSSSNGIIWLGILLAYKGLLLLFGCFLAWKTRNVDIeEFNE 202
                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 17540172 1208 TKWLLYSTVLCFFTWVAWITLYLVLDHEF--RDTVIVVELVACATILLGFLFGPKIYIL 1264
Cdd:cd15047  203 SKYIGISIYNVLFLSVIGVPLSFVLTDSPdtSYLIISAAILFCTTATLCLLFVPKFWLL 261
7tmC_RAIG2_GPRC5B cd15278
retinoic acid-inducible orphan G-protein-coupled receptor 2; class C family of ...
1072-1265 4.57e-12

retinoic acid-inducible orphan G-protein-coupled receptor 2; class C family of seven-transmembrane G protein-coupled receptors, group 5, member B; Retinoic acid-inducible G-protein-coupled receptors (RAIGs), also referred to as GPCR class C group 5, are a group consisting of four orphan receptors RAIG1 (GPRC5A), RAIG2 (GPRC5B), RAIG3 (GPRC5C), and RAIG4 (GPRC5D). Unlike other members of the class C GPCRs which contain a large N-terminal extracellular domain, RAIGs have a shorter N-terminus. Thus, it is unlikely that RAIGs bind an agonist at its N-terminus domain. Instead, the agonists may bind to the seven-transmembrane domain of these receptors. In addition, RAIG2 and RAIG3 contain a cleavable signal peptide whereas RAIG1 and RAIG4 do not. Although their expression is induced by retinoic acid (vitamin A analog), their biological function is not clearly understood. To date, no ligand is known for the members of RAIG family. Three receptor types (RAIG1-3) are found in vertebrates, while RAIG4 is only present in mammals. They show distinct tissue distribution with RAIG1 being primarily expressed in the lung, RAIG2 in the brain and placenta, RAIG3 in the brain, kidney and liver, and RAIG4 in the skin. RAIG2 (GPRC5B), a mammalian Boss (Bride of sevenless) homolog, has been shown to activate obesity-associated inflammatory signaling in adipocytes, and that the GPRC5B knockout mice have been shown to be resistance to high-fat diet-induced obesity and insulin resistance.


Pssm-ID: 320405  Cd Length: 244  Bit Score: 67.53  E-value: 4.57e-12
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFGTaihiSFWNYWLLLFFIVGVQIALSISWFL 1151
Cdd:cd15278   54 FGLTFAFIIQEDETICSLRRFLWGVLFALCFSCLLAQGWRLRRLVRHGKGP----SGWHLTGLALCLMLVQVIIAVEWLI 129
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1152 EPFMSTigvidtnvQRMMCTMGKVEFVVSNFYVMILIFMALFISMLNR--NIKRNYKETKWLLYSTVLCFFTWVAWITLY 1229
Cdd:cd15278  130 LTVLRD--------GRPACQYEPMDFVMALIYVMVLLVATLGLALFTLcgKFQKWKKNGICLLITCFLSVLIWVAWMTMY 201
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|..
gi 17540172 1230 LVLDHEFR------DTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15278  202 LYGNDELGrsddwnDPTLAIALVASGWVFLIFHAIPEVHCTL 243
PBP1_mGluR cd06362
ligand binding domain of metabotropic glutamate receptors (mGluR); Ligand binding domain of ...
669-938 6.40e-12

ligand binding domain of metabotropic glutamate receptors (mGluR); Ligand binding domain of the metabotropic glutamate receptors (mGluR), which are members of the family C of G-protein-coupled receptors that transduce extracellular signals into G-protein activation and ultimately into cellular responses. mGluRs bind to glutamate and function as an excitatory neurotransmitter; they are involved in learning, memory, anxiety, and the perception of pain. Eight subtypes of mGluRs have been cloned so far, and are classified into three groups according to their sequence similarities, transduction mechanisms, and pharmacological profiles. Group I is composed of mGlu1R and mGlu5R that both stimulate PLC hydrolysis. Group II includes mGlu2R and mGlu3R, which inhibit adenylyl cyclase, as do mGlu4R, mGlu6R, mGlu7R, and mGlu8R, which form group III.


Pssm-ID: 380585 [Multi-domain]  Cd Length: 460  Bit Score: 69.63  E-value: 6.40e-12
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  669 PSSRNQALALLKLLNRMQWQFVTAALSEQDPESlSLFRAFERLALDRGVCLAEVLNIGGSRLDN--------IRSTTNVT 740
Cdd:cd06362  158 PSDSFQAKAIVDILLHFNWTYVSVVYSEGSYGE-EGYKAFKKLARKAGICIAESERISQDSDEKdyddviqkLLQKKNAR 236
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  741 IV--FSTARDAADYLIASKiRGNHVN--VMMGeAHDW---YLHAPNNKELFPGTVSVQPRNILYGDFREWLETTTPLT-- 811
Cdd:cd06362  237 VVvlFADQEDIRGLLRAAK-RLGASGrfIWLG-SDGWgtnIDDLKGNEDVALGALTVQPYSEEVPRFDDYFKSLTPSNnt 314
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  812 ----LPELWywsyiESRYGCALsqksKVIYGKMCTGDELLNIESLG--RMTKAGYLSRGVERFLFAMDSVYKSLCPAQNG 885
Cdd:cd06362  315 rnpwFREFW-----QELFQCSF----RPSRENSCNDDKLLINKSEGykQESKVSFVIDAVYAFAHALHKMHKDLCPGDTG 385
                        250       260       270       280       290       300       310
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 17540172  886 LClefyEQGRRQI-----LTQLKKTSTEDDV----------------EIYEFLPDINNHFTYHLIANWTLTTGL 938
Cdd:cd06362  386 LC----QDLMKCIdgselLEYLLNVSFTGEAggeirfdengdgpgryDIMNFQRNNDGSYEYVRVGVWDQYTQK 455
7tmC_GPRC6A cd15281
class C of seven-transmembrane G protein-coupled receptors, subtype 6A; GRPC6A (GPCR, class C, ...
1072-1265 5.78e-11

class C of seven-transmembrane G protein-coupled receptors, subtype 6A; GRPC6A (GPCR, class C, group 6, subtype A) is a widely expressed amino acid-sensing GPCR that is most closely related to CaSR. GPRC6A is most potently activated by the basic amino acids L-arginine, L-lysine, and L-ornithine and less potently by small aliphatic amino acids. Moreover, the receptor can be either activated or modulated by divalent cations such as Ca2+ and Mg2+. GPRC6A is expressed in the testis, but not the ovary and specifically also binds to the osteoblast-derived hormone osteocalcin (OCN), which regulates testosterone production by the testis and male fertility independently of the hypothalamic-pituitary axis. Furthermore, GPRC6A knockout studies suggest that GRPC6A is involved in regulation of bone metabolism, male reproduction, energy homeostasis, glucose metabolism, and in activation of inflammation response, as well as prostate cancer growth and progression, among others. GPRC6A has been suggested to couple to the Gq subtype of G proteins, leading to IP3 production and intracellular calcium mobilization. GPRC6A contains a large extracellular Venus flytrap-like domain in the N-terminus, cysteine-rich domain (CRD), and seven-transmembrane (7TM) domain, which are characteristics of the class C GPCRs. The Venus flytrap-like domain shares strong sequence homology to bacterial periplasmic binding proteins and possess the orthosteric amino acid and calcium binding sites for members of the class C, including CaSR, GABA-B, GPRC6A, mGlu, and TAS1R receptors.


Pssm-ID: 320408  Cd Length: 249  Bit Score: 64.41  E-value: 5.78e-11
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFG-TAIHISFWNYWLLLFFIVGVQIALSISW- 1149
Cdd:cd15281   52 FISTVFFIGEPSDLTCKTRQTLFGISFTLCVSCILVKSLKILLAFSFDPKlQELLKCLYKPIMIVFICTGIQVIICTVWl 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1150 -FLEPFMSTIGVIdTNVQRMMCTMGK-VEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWVAWIT 1227
Cdd:cd15281  132 vFYKPFVDKNFSL-PESIILECNEGSyVAFGLMLGYIALLAFICFIFAFKGRKLPENYNEAKFITFGMLIYFIAWITFIP 210
                        170       180       190
                 ....*....|....*....|....*....|....*....
gi 17540172 1228 LYLVLDHEFRDTV-IVVELVACATILLGFLFgPKIYILL 1265
Cdd:cd15281  211 IYATTFGKYVPAVeMIVILISNYGILSCTFL-PKCYIIL 248
7tmC_RAIG_GPRC5 cd15043
retinoic acid-inducible orphan G-protein-coupled receptors; class C family of ...
1076-1265 2.00e-10

retinoic acid-inducible orphan G-protein-coupled receptors; class C family of seven-transmembrane G protein-coupled receptors, group 5; Retinoic acid-inducible G-protein-coupled receptors (RAIGs), also referred to as GPCR class C group 5, are a group consisting of four orphan receptors RAIG1 (GPRC5A), RAIG2 (GPRC5B), RAIG3 (GPRC5C), and RAIG4 (GPRC5D). Unlike other members of the class C GPCRs which contain a large N-terminal extracellular domain, RAIGs have a shorter N-terminus. Thus, it is unlikely that RAIGs bind an agonist at its N-terminus domain. Instead, agonists may bind to the seven-transmembrane domain of these receptors. In addition, RAIG2 and RAIG3 contain a cleavable signal peptide whereas RAIG1 and RAIG4 do not. Although their expression is induced by retinoic acid (vitamin A analog), their biological function is not clearly understood. To date, no ligand is known for the members of RAIG family. Three receptor types (RAIG1-3) are found in vertebrates, while RAIG4 is only present in mammals. They show distinct tissue distribution with RAIG1 being primarily expressed in the lung, RAIG2 in the brain and placenta, RAIG3 in the brain, kidney and liver, and RAIG4 in the skin. RAIG1 is evolutionarily conserved from mammals to fish. RAIG1 has been to shown to act as a tumor suppressor in non-small cell lung carcinoma as well as oral squamous cell carcinoma, but it could also act as an oncogene in breast cancer, colorectal cancer, and pancreatic cancer. Studies have shown that overexpression of RAIG1 decreases intracellular cAMP levels. Moreover, knocking out RAIG1 induces the activation of the NF-kB and STAT3 signaling pathways leading to cell proliferation and resistance to apoptosis. RAIG2 (GPRC5B), a mammalian Boss (Bride of sevenless) homolog, activates obesity-associated inflammatory signaling in adipocytes, and GPRC5B knockout mice show resistance to high-fat diet-induced obesity and insulin resistance. The specific functions of RAIG3 and RAIG4 are unknown; however, they may play roles in mediating the effects of retinoic acid on embryogenesis, differentiation, and tumorigenesis through interactions with G-protein signaling pathways.


Pssm-ID: 320171  Cd Length: 248  Bit Score: 62.97  E-value: 2.00e-10
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1076 FFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFGTAIhisfwnyWLLLFFIVG---VQIALSISWFLe 1152
Cdd:cd15043   58 FAFIIGLDGSTCPTRRFLFGVLFAICFSCLLAHAVSLTKLVRGRKGPSG-------WVILGLALGlslVQVIIAIEWLV- 129
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1153 pfmstIGVIDTNVQ---RMMCTMGKVEFVVSNFYVMILIFMALFISM--LNRNIKRNYKETKWLLYSTVLCFFTWVAWIT 1227
Cdd:cd15043  130 -----LTMNRTNVNvfsELSCARRNMDFVMALIYVMFLLALTFLMASftLCGSFKRWKRHGAFILLTMLLSVAIWVAWIT 204
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|...
gi 17540172 1228 LYLV-----LDHEFRDTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15043  205 MYMLgnvlqFDRRWDDPTLAIALAANGWVFVLFYVIPEFWLLT 247
7tmC_V2R_pheromone cd15283
vomeronasal type-2 pheromone receptors, member of the class C family of seven-transmembrane G ...
1075-1265 5.26e-10

vomeronasal type-2 pheromone receptors, member of the class C family of seven-transmembrane G protein-coupled receptors; This group represents vomeronasal type-2 pheromone receptors (V2Rs). Members of the V2R family of vomeronasal GPCRs are involved in detecting protein pheromones for social and sexual cues between the same species. V2Rs and G-alpha(o) protein are coexpressed in the basal layer of the vomeronasal organ (VNO), which is the sensory organ of the accessory olfactory system present in amphibians, reptiles, and non-primate mammals such as mice and rodents, but it is non-functional or absent in humans, apes, and monkeys. On the other hand, members of the V1R receptor family and G-alpha(i2) protein are coexpressed in the apical neurons of the VNO. Activation of V1R or V2R causes activation of phospholipase pathway, producing the second messengers diacylglycerol (DAG) and IP3. However, in contrast to V1Rs, V2Rs contain the long N-terminal extracellular domain, which is believed to bind pheromones.


Pssm-ID: 320410 [Multi-domain]  Cd Length: 252  Bit Score: 61.52  E-value: 5.26e-10
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1075 AFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKatqlrnaeTLGFGTAIHISFWNYWLLLFFIVG-----------VQI 1143
Cdd:cd15283   55 SLLFIGQPSTWTCMLRQTAFGISFVLCISCILAK--------TIVVVAAFKATRPGSNIMKWFGPGqqraiifictlVQV 126
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1144 ALSISWFLE--PFMstigVIDTNVQR----MMCTMGKVE-FVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTV 1216
Cdd:cd15283  127 VICAIWLATspPFP----DKNMHSEHgkiiLECNEGSVVaFYCVLGYIGLLALVSFLLAFLARKLPDNFNEAKFITFSML 202
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|....*....
gi 17540172 1217 LCFFTWVAWITLYLVLDHEFRDTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15283  203 VFCAVWVAFVPAYISSPGKYMVAVEIFAILASSAGLLGCIFAPKCYIIL 251
7tmC_V2R-like cd15280
vomeronasal type-2 receptor-like proteins, member of the class C family of seven-transmembrane ...
1074-1265 1.08e-09

vomeronasal type-2 receptor-like proteins, member of the class C family of seven-transmembrane G protein-coupled receptors; This group represents vomeronasal type-2 receptor-like proteins that are closely related to the V2R family of vomeronasal GPCRs. Members of the V2R family of vomeronasal GPCRs are involved in detecting protein pheromones for social and sexual cues between the same species. V2Rs and G-alpha(o) protein are coexpressed in the basal layer of the vomeronasal organ (VNO), which is the sensory organ of the accessory olfactory system present in amphibians, reptiles, and non-primate mammals such as mice and rodents, but it is non-functional or absent in humans, apes, and monkeys. On the other hand, members of the V1R receptor family and G-alpha(i2) protein are co-expressed in the apical neurons of the VNO. Activation of V1R or V2R causes activation of phospholipase pathway, generating the secondary messengers diacylglycerol (DAG) and IP3. However, in contrast to V1Rs, V2Rs contain the long N-terminal extracellular domain, which is believed to bind pheromones. Human V2R1-like protein, also known as putative calcium-sensing receptor-like 1 (CASRL1), is not included here because it is a nonfunctional pseudogene.


Pssm-ID: 320407 [Multi-domain]  Cd Length: 253  Bit Score: 60.57  E-value: 1.08e-09
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1074 TAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFGTAIHISFWNYWLLLFFIVGV--QIALSISWF- 1150
Cdd:cd15280   54 TSILFIGKPENWSCMARQITLALGFSLCLSSILGKTISLFLRYRASKSETRLDSMHPIYQKIIVLICVliEVGICTAYLi 133
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1151 LEPFMSTIGVIDTNVQRMM-CTMGKVEFVVSNF----YVMILIFMALFISmlnRNIKRNYKETKWLLYSTVLCFFTWVAW 1225
Cdd:cd15280  134 LEPPRMYKNTEVQNVKIIFeCNEGSIEFLCSIFgfdvFLALLCFLTAFVA---RKLPDNFNEGKFITFGMLVFFIVWISF 210
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|
gi 17540172 1226 ITLYLVLDHEFRDTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15280  211 VPAYLSTRGKFKVAVEIFAILASSFGLLGCIFVPKCYIIL 250
7tmC_mGluR2 cd15447
metabotropic glutamate receptor 2 in group 2, member of the class C family of ...
1072-1265 1.24e-09

metabotropic glutamate receptor 2 in group 2, member of the class C family of seven-transmembrane G protein-coupled receptors; The metabotropic glutamate receptors (mGluRs) in group 2 include mGluR 2 and 3. They are homodimeric class C G-protein coupled receptors which are activated by glutamate, the major excitatory neurotransmitter of the CNS. mGluRs are involved in regulating neuronal excitability and synaptic transmission via intracellular activation of second messenger signaling pathways. While the ionotropic glutamate receptor subtypes (AMPA, NMDA, and kainite) mediate fast excitatory postsynaptic transmission, mGluRs are known to mediate slower excitatory postsynaptic responses and to be involved in synaptic plasticity in the mammalian brain. In addition to seven-transmembrane helices, the class C GPCRs are characterized by a large N-terminal extracellular Venus flytrap-like domain, which is composed of two adjacent lobes separated by a cleft which binds an endogenous ligand. Moreover, they exist as either homo- or heterodimers, which are essential for their function. For instance, mGluRs form homodimers via interactions between the N-terminal Venus flytrap domains and the intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD). At least eight different subtypes of metabotropic receptors (mGluR1-8) have been identified and further classified into three groups based on their sequence homology, pharmacological properties, and signaling pathways. Group 1 (mGluR1 and mGluR5) receptors are predominantly located postsynaptically on neurons and are involved in long-term synaptic plasticity in the brain, including long-term potentiation (LTP) in the hippocampus and long-term depression (LTD) in the cerebellum. They are coupled to G(q/11) proteins, thereby activating phospholipase C to generate inositol-1,4,5-triphosphate (IP3) and diacyglycerol (DAG), which in turn lead to Ca2+ release and protein kinase C activation, respectively. Group 1 mGluR expression is shown to be strongly upregulated in animal models of epilepsy, brain injury, inflammatory, and neuropathic pain, as well as in patients with amyotrophic lateral sclerosis or multiple sclerosis. Group 2 (mGluR2 and mGluR3) and 3 (mGluR4, mGluR6, mGluR7, and mGluR8) receptors are predominantly localized presynaptically in the active region of neurotransmitter release. They are coupled to G(i/o) proteins, which leads to inhibition of adenylate cyclase activity and cAMP formation, and consequently to a decrease in protein kinase A (PKA) activity. Ultimately, activation of these receptors leads to inhibition of neurotransmitter release such as glutamate and GABA via inhibition of Ca2+ channels and activation of K+ channels. Furthermore, while activation of Group 1 mGluRs increases NMDA (N-methyl-D-aspartate) receptor activity and risk of neurotoxicity, Group 2 and 3 mGluRs decrease NMDA receptor activity and prevent neurotoxicity.


Pssm-ID: 320563  Cd Length: 254  Bit Score: 60.71  E-value: 1.24e-09
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLR---NAETLGFGTAIHISFWNYWLLLFFIVGVQIALSIS 1148
Cdd:cd15447   52 YLMTFIFIAKPSTAVCTLRRLGLGTSFAVCYSALLTKTNRIArifSGAKDGAQRPRFISPASQVAICLALISCQLLVVLI 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1149 WFLepfMSTIGV-IDTNVQR-----MMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTW 1222
Cdd:cd15447  132 WLL---VEAPGTrKETAPERryvvtLKCNSRDSSMLISLTYNVLLIILCTLYAFKTRKCPENFNEAKFIGFTMYTTCIIW 208
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|....*
gi 17540172 1223 VAWITLYLVLDHEFR--DTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15447  209 LAFLPIFYVTSSDYRvqTTTMCISVSLSGSVVLGCLFAPKLHIIL 253
7tmC_TAS1R2a-like cd15287
type 1 taste receptor subtype 2a and similar proteins, member of the class C of ...
1076-1265 3.06e-09

type 1 taste receptor subtype 2a and similar proteins, member of the class C of seven-transmembrane G protein-coupled receptors; This group includes TAS1R2a and its similar proteins found in fish. They are members of the type I taste receptor (TAS1R) family that belongs to the class C of G protein-coupled receptors. The functional TAS1Rs are obligatory heterodimers built from three known members, TAS1R1-3. TAS1R1 combines with TAS1R3 to form an umami taste receptor, which is responsible for the perception of savory taste, such as the food additive mono-sodium glutamate (MSG); whereas the combination of TAS1R2-TAS1R3 forms a sweet-taste receptor for sugars and D-amino acids. On the other hand, the type II taste receptors (TAS2Rs), which belong to the class A family of GPCRs, recognize bitter tasting compounds. In the case of sweet, for example, the TAS1R2-TAS1R3 heterodimer activates phospholipase C (PLC) via alpha-gustducin, a heterodimeric G protein that is involved in perception of sweet and bitter tastes. This activation leads to generation of inositol (1, 4, 5)-trisphosphate (IP3) and diacylglycerol (DAG), and consequently increases intracellular Ca2+ mobilization and activates a cation channel, TRPM5. In contrast to the TAS1R2-TAS1R3 heterodimer, TAS1R3 alone could activate adenylate cyclase leading to cAMP formation in the absence of alpha-gustducin. Each TAS1R contains a large extracellular Venus flytrap-like domain in the N-terminus, cysteine-rich domain (CRD) and seven-transmembrane (7TM) domain, which are characteristics of the class C GPCRs. The Venus flytrap-like domain shares strong sequence homology to bacterial periplasmic binding proteins and possess the orthosteric amino acid and calcium binding sites for members of the class C, including CaSR, GABA-B1, GPRC6A, mGlu, and TAS1R receptors.


Pssm-ID: 320414  Cd Length: 252  Bit Score: 59.31  E-value: 3.06e-09
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1076 FFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLrnaeTLGFGTA-----IHISFWNY---WLLLFFIVGVQIALSI 1147
Cdd:cd15287   56 FFYFGKPTVASCILRYFPFLLFYTVCLACFVVRSFQI----VCIFKIAakfpkLHSWWVKYhgqWLLIAVAFVIQALLLI 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1148 SWFL----EPFMSTIGVIDTNVqrMMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWV 1223
Cdd:cd15287  132 TGFSfsppKPYNDTSWYPDKII--LSCDINLKATSMSLVLLLSLCCLCFIFSYMGKDLPKNYNEAKAITFCLLLLILTWI 209
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|....*
gi 17540172 1224 AWITLYLVLDHEFrdtVIVVELVACATILLGFLFG---PKIYILL 1265
Cdd:cd15287  210 IFATEYMLYRGKY---IQLLNALAVLSSLYSFLLWyflPKCYIII 251
7tmC_mGluR1 cd15449
metabotropic glutamate receptor 1 in group 1, member of the class C family of ...
1072-1266 3.54e-09

metabotropic glutamate receptor 1 in group 1, member of the class C family of seven-transmembrane G protein-coupled receptors; Group 1 mGluRs includes mGluR1 and mGluR5, as well as their closely related invertebrate receptors. They are homodimeric class C G-protein coupled receptors which are activated by glutamate, the major excitatory neurotransmitter of the CNS. mGluRs are involved in regulating neuronal excitability and synaptic transmission via intracellular activation of second messenger signaling pathways. While the ionotropic glutamate receptor subtypes (AMPA, NMDA, and kainite) mediate fast excitatory postsynaptic transmission, mGluRs are known to mediate slower excitatory postsynaptic responses and to be involved in synaptic plasticity in the mammalian brain. In addition to seven-transmembrane helices, the class C GPCRs are characterized by a large N-terminal extracellular Venus flytrap-like domain, which is composed of two adjacent lobes separated by a cleft which binds an endogenous ligand. Moreover, they exist as either homo- or heterodimers, which are essential for their function. For instance, mGluRs form homodimers via interactions between the N-terminal Venus flytrap domains and the intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD). At least eight different subtypes of metabotropic receptors (mGluR1-8) have been identified and further classified into three groups based on their sequence homology, pharmacological properties, and signaling pathways. Group 1 (mGluR1 and mGluR5) receptors are predominantly located postsynaptically on neurons and are involved in long-term synaptic plasticity in the brain, including long-term potentiation (LTP) in the hippocampus and long-term depression (LTD) in the cerebellum. They are coupled to G(q/11) proteins, thereby activating phospholipase C to generate inositol-1,4,5-triphosphate (IP3) and diacyglycerol (DAG), which in turn lead to Ca2+ release and protein kinase C activation, respectively. Group 1 mGluR expression is shown to be strongly upregulated in animal models of epilepsy, brain injury, inflammatory, and neuropathic pain, as well as in patients with amyotrophic lateral sclerosis or multiple sclerosis. Group 2 (mGluR2 and mGluR3) and 3 (mGluR4, mGluR6, mGluR7, and mGluR8) receptors are predominantly localized presynaptically in the active region of neurotransmitter release. They are coupled to G(i/o) proteins, which leads to inhibition of adenylate cyclase activity and cAMP formation, and consequently to a decrease in protein kinase A (PKA) activity. Ultimately, activation of these receptors leads to inhibition of neurotransmitter release such as glutamate and GABA via inhibition of Ca2+ channels and activation of K+ channels. Furthermore, while activation of Group 1 mGluRs increases NMDA (N-methyl-D-aspartate) receptor activity and risk of neurotoxicity, Group 2 and 3 mGluRs decrease NMDA receptor activity and prevent neurotoxicity.


Pssm-ID: 320565  Cd Length: 250  Bit Score: 59.26  E-value: 3.54e-09
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLR-----NAETLGFGTAIHISFWNYWLLLFFIVGVQIALS 1146
Cdd:cd15449   52 YVCPFTLIAKPTTTSCYLQRLLVGLSSAMCYSALVTKTNRIArilagSKKKICTRKPRFMSAWAQVVIASILISVQLTLV 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1147 ISWF-LEPFMSTIGVIDTNVQRMMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWVAW 1225
Cdd:cd15449  132 VTLIiMEPPMPILSYPSIKEVYLICNTSNLGVVAPLGYNGLLIMSCTYYAFKTRNVPANFNEAKYIAFTMYTTCIIWLAF 211
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|.
gi 17540172 1226 ITLYLVLDHEFRDTVIVVELvaCATILLGFLFGPKIYILLS 1266
Cdd:cd15449  212 VPIYFGSNYKIITTCFAVSL--SVTVALGCMFTPKMYIIIA 250
7tmC_TAS1R cd15046
type 1 taste receptors, member of the class C of seven-transmembrane G protein-coupled ...
1072-1265 3.83e-09

type 1 taste receptors, member of the class C of seven-transmembrane G protein-coupled receptors; This subfamily represents the type I taste receptors (TAS1Rs) that belongs to the class C family of G protein-coupled receptors. The functional TAS1Rs are obligatory heterodimers built from three known members, TAS1R1-3. TAS1R1 combines with TAS1R3 to form an umami taste receptor, which is responsible for the perception of savory taste, such as the food additive mono-sodium glutamate (MSG); whereas the combination of TAS1R2-TAS1R3 forms a sweet-taste receptor for sugars and D-amino acids. On the other hand, the type II taste receptors (TAS2Rs), which belong to the class A family of GPCRs, recognize bitter tasting compounds. In the case of sweet, for example, the TAS1R2-TAS1R3 heterodimer activates phospholipase C (PLC) via alpha-gustducin, a heterodimeric G protein that is involved in perception of sweet and bitter tastes. This activation leads to generation of inositol (1, 4, 5)-trisphosphate (IP3) and diacylglycerol (DAG), and consequently increases intracellular Ca2+ mobilization and activates a cation channel, TRPM5. In contrast to the TAS1R2-TAS1R3 heterodimer, TAS1R3 alone could activate adenylate cyclase leading to cAMP formation in the absence of alpha-gustducin. Each TAS1R contains a large extracellular Venus flytrap-like domain in the N-terminus, cysteine-rich domain (CRD) and seven-transmembrane (7TM) domain, which are characteristics of the class C GPCRs. The Venus flytrap-like domain shares strong sequence homology to bacterial periplasmic binding proteins and possess the orthosteric amino acid and calcium binding sites for members of the class C, including CaSR, GABA-B1, GPRC6A, mGlu, and TAS1R receptors.


Pssm-ID: 320174 [Multi-domain]  Cd Length: 253  Bit Score: 59.08  E-value: 3.83e-09
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFGTAIHISFW----NYWLLLFFIVGVQIALSI 1147
Cdd:cd15046   52 YMSVPVYFGPPKVSTCLLRQALFPLCFTVCLACIAVRSFQIVCIFKMASRFPRAYSYWvkyhGPYVSIAFITVLKMVIVV 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1148 ----SWFLEPFMSTIGVIDTNVQrMMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWV 1223
Cdd:cd15046  132 igmlATPPSPTTDTDPDPKITIV-SCNPNYRNSSLFNTSLDLLLSVVCFSFSYMGKDLPTNYNEAKFITFSLTFYFTSWI 210
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|...
gi 17540172 1224 AWITLYLVLDHEFRDTV-IVVELVACATILLGFlFGPKIYILL 1265
Cdd:cd15046  211 SFCTFMLAYSGVLVTIVdLLATLLSLLAFSLGY-FLPKCYIIL 252
7tmC_TAS1R3 cd15290
type 1 taste receptor subtype 3, member of the class C of seven-transmembrane G ...
1078-1265 5.68e-09

type 1 taste receptor subtype 3, member of the class C of seven-transmembrane G protein-coupled receptors; This group represents TAS1R3, which is a member of the type I taste receptor (TAS1R) family that belongs to the class C of G protein-coupled receptors. The functional TAS1Rs are obligatory heterodimers built from three known members, TAS1R1-3. TAS1R1 combines with TAS1R3 to form an umami taste receptor, which is responsible for the perception of savory taste, such as the food additive mono-sodium glutamate (MSG); whereas the combination of TAS1R2-TAS1R3 forms a sweet-taste receptor for sugars and D-amino acids. On the other hand, the type II taste receptors (TAS2Rs), which belong to the class A family of GPCRs, recognize bitter tasting compounds. In the case of sweet, for example, the TAS1R2-TAS1R3 heterodimer activates phospholipase C (PLC) via alpha-gustducin, a heterodimeric G protein that is involved in perception of sweet and bitter tastes. This activation leads to generation of inositol (1, 4, 5)-trisphosphate (IP3) and diacylglycerol (DAG), and consequently increases intracellular Ca2+ mobilization and activates a cation channel, TRPM5. In contrast to the TAS1R2-TAS1R3 heterodimer, TAS1R3 alone could activate adenylate cyclase leading to cAMP formation in the absence of alpha-gustducin. Each TAS1R contains a large extracellular Venus flytrap-like domain in the N-terminus, cysteine-rich domain (CRD) and seven-transmembrane (7TM) domain, which are characteristics of the class C GPCRs. The Venus flytrap-like domain shares strong sequence homology to bacterial periplasmic binding proteins and possess the orthosteric amino acid and calcium binding sites for members of the class C, including CaSR, GABA-B1, GPRC6A, mGlu, and TAS1R receptors.


Pssm-ID: 320417 [Multi-domain]  Cd Length: 253  Bit Score: 58.53  E-value: 5.68e-09
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1078 FVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFGTAIHISFWN---YWLLLFFIVGVQIALSiSWFLE-- 1152
Cdd:cd15290   58 FLGQPSDVVCRLQQPLNALFLTVCLSTILSISLQIFLVTEFPKCAASHLHWLRgpgSWLVVLICCLVQAGLC-GWYVQdg 136
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1153 -PFMSTIGVIDTNVQRMM--CTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWVAWITLY 1229
Cdd:cd15290  137 pSLSEYDAKMTLFVEVFLrcPVEPWLGFGLMHGFNGALALISFMCTFMAQKPLKQYNLARDITFSTLIYCVTWVIFIPIY 216
                        170       180       190
                 ....*....|....*....|....*....|....*.
gi 17540172 1230 LVLDHEFRDTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15290  217 AGLQVKLRSIAQVGFILLSNLGLLAAYYLPKCYLLL 252
7tmC_mGluR6 cd15453
metabotropic glutamate receptor 6 in group 3, member of the class C family of ...
1070-1265 5.71e-09

metabotropic glutamate receptor 6 in group 3, member of the class C family of seven-transmembrane G protein-coupled receptors; The receptors in group 3 include mGluRs 4, 6, 7, and 8. They are homodimeric class C G-protein coupled receptors which are activated by glutamate, the major excitatory neurotransmitter of the CNS. mGluRs are involved in regulating neuronal excitability and synaptic transmission via intracellular activation of second messenger signaling pathways. While the ionotropic glutamate receptor subtypes (AMPA, NMDA, and kainite) mediate fast excitatory postsynaptic transmission, mGluRs are known to mediate slower excitatory postsynaptic responses and to be involved in synaptic plasticity in the mammalian brain. In addition to seven-transmembrane helices, the class C GPCRs are characterized by a large N-terminal extracellular Venus flytrap-like domain, which is composed of two adjacent lobes separated by a cleft which binds an endogenous ligand. Moreover, they exist as either homo- or heterodimers, which are essential for their function. For instance, mGluRs form homodimers via interactions between the N-terminal Venus flytrap domains and the intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD). At least eight different subtypes of metabotropic receptors (mGluR1-8) have been identified and further classified into three groups based on their sequence homology, pharmacological properties, and signaling pathways. Group 1 (mGluR1 and mGluR5) receptors are predominantly located postsynaptically on neurons and are involved in long-term synaptic plasticity in the brain, including long-term potentiation (LTP) in the hippocampus and long-term depression (LTD) in the cerebellum. They are coupled to G(q/11) proteins, thereby activating phospholipase C to generate inositol-1,4,5-triphosphate (IP3) and diacyglycerol (DAG), which in turn lead to Ca2+ release and protein kinase C activation, respectively. Group 1 mGluR expression is shown to be strongly upregulated in animal models of epilepsy, brain injury, inflammatory, and neuropathic pain, as well as in patients with amyotrophic lateral sclerosis or multiple sclerosis. Group 2 (mGluR2 and mGluR3) and 3 (mGluR4, mGluR6, mGluR7, and mGluR8) receptors are predominantly localized presynaptically in the active region of neurotransmitter release. They are coupled to G(i/o) proteins, which leads to inhibition of adenylate cyclase activity and cAMP formation, and consequently to a decrease in protein kinase A (PKA) activity. Ultimately, activation of these receptors leads to inhibition of neurotransmitter release such as glutamate and GABA via inhibition of Ca2+ channels and activation of K+ channels. Furthermore, while activation of Group 1 mGluRs increases NMDA (N-methyl-D-aspartate) receptor activity and risk of neurotoxicity, Group 2 and 3 mGluRs decrease NMDA receptor activity and prevent neurotoxicity.


Pssm-ID: 320569 [Multi-domain]  Cd Length: 273  Bit Score: 58.89  E-value: 5.71e-09
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1070 ILYSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFGTAI---HISFWNYWLLLFFIVGVQIALS 1146
Cdd:cd15453   50 LIYAITFLMVAEPGAAVCAFRRLFLGLGTTLSYSALLTKTNRIYRIFEQGKRSVTpppFISPTSQLVITFSLTSLQVVGV 129
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1147 ISWF-LEPFMStigVIDTNVQR----------MMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYST 1215
Cdd:cd15453  130 IAWLgAQPPHS---VIDYEEQRtvdpeqargvLKCDMSDLSLIGCLGYSLLLMVTCTVYAIKARGVPETFNEAKPIGFTM 206
                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 17540172 1216 VLCFFTWVAWITLYLVLDHE-----FRDTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15453  207 YTTCIIWLAFVPIFFGTAQSaekiyIQTTTLTVSLSLSASVSLGMLYVPKTYVIL 261
7tmC_mGluR4 cd15452
metabotropic glutamate receptor 4 in group 3, member of the class C family of ...
1072-1265 7.68e-09

metabotropic glutamate receptor 4 in group 3, member of the class C family of seven-transmembrane G protein-coupled receptors; The receptors in group 3 include mGluRs 4, 6, 7, and 8. They are homodimeric class C G-protein coupled receptors which are activated by glutamate, the major excitatory neurotransmitter of the CNS. mGluRs are involved in regulating neuronal excitability and synaptic transmission via intracellular activation of second messenger signaling pathways. While the ionotropic glutamate receptor subtypes (AMPA, NMDA, and kainite) mediate fast excitatory postsynaptic transmission, mGluRs are known to mediate slower excitatory postsynaptic responses and to be involved in synaptic plasticity in the mammalian brain. In addition to seven-transmembrane helices, the class C GPCRs are characterized by a large N-terminal extracellular Venus flytrap-like domain, which is composed of two adjacent lobes separated by a cleft which binds an endogenous ligand. Moreover, they exist as either homo- or heterodimers, which are essential for their function. For instance, mGluRs form homodimers via interactions between the N-terminal Venus flytrap domains and the intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD). At least eight different subtypes of metabotropic receptors (mGluR1-8) have been identified and further classified into three groups based on their sequence homology, pharmacological properties, and signaling pathways. Group 1 (mGluR1 and mGluR5) receptors are predominantly located postsynaptically on neurons and are involved in long-term synaptic plasticity in the brain, including long-term potentiation (LTP) in the hippocampus and long-term depression (LTD) in the cerebellum. They are coupled to G(q/11) proteins, thereby activating phospholipase C to generate inositol-1,4,5-triphosphate (IP3) and diacyglycerol (DAG), which in turn lead to Ca2+ release and protein kinase C activation, respectively. Group 1 mGluR expression is shown to be strongly upregulated in animal models of epilepsy, brain injury, inflammatory, and neuropathic pain, as well as in patients with amyotrophic lateral sclerosis or multiple sclerosis. Group 2 (mGluR2 and mGluR3) and 3 (mGluR4, mGluR6, mGluR7, and mGluR8) receptors are predominantly localized presynaptically in the active region of neurotransmitter release. They are coupled to G(i/o) proteins, which leads to inhibition of adenylate cyclase activity and cAMP formation, and consequently to a decrease in protein kinase A (PKA) activity. Ultimately, activation of these receptors leads to inhibition of neurotransmitter release such as glutamate and GABA via inhibition of Ca2+ channels and activation of K+ channels. Furthermore, while activation of Group 1 mGluRs increases NMDA (N-methyl-D-aspartate) receptor activity and risk of neurotoxicity, Group 2 and 3 mGluRs decrease NMDA receptor activity and prevent neurotoxicity.


Pssm-ID: 320568 [Multi-domain]  Cd Length: 327  Bit Score: 59.22  E-value: 7.68e-09
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFGTAI---HISFWNYWLLLFFIVGVQIALSIS 1148
Cdd:cd15452   52 YATTFLMIAEPDLGTCSLRRIFLGLGMSISYAALLTKTNRIYRIFEQGKRSVSaprFISPASQLVITFSLISLQLLGVCV 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1149 WFL-EPFMStigVIDTNVQR----------MMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVL 1217
Cdd:cd15452  132 WFLvDPSHS---VVDYEDQRtpdpqfargvLKCDISDLSLICLLGYSMLLMVTCTVYAIKTRGVPETFNEAKPIGFTMYT 208
                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|...
gi 17540172 1218 CFFTWVAWITLYLVLDHE-----FRDTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15452  209 TCIIWLAFIPIFFGTSQSaekmyIQTTTLTISVSLSASVSLGMLYMPKVYVIL 261
7tmC_mGluR3 cd15448
metabotropic glutamate receptor 3 in group 2, member of the class C family of ...
1072-1265 8.67e-09

metabotropic glutamate receptor 3 in group 2, member of the class C family of seven-transmembrane G protein-coupled receptors; The metabotropic glutamate receptors (mGluRs) in group 2 include mGluR 2 and 3. They are homodimeric class C G-protein coupled receptors which are activated by glutamate, the major excitatory neurotransmitter of the CNS. mGluRs are involved in regulating neuronal excitability and synaptic transmission via intracellular activation of second messenger signaling pathways. While the ionotropic glutamate receptor subtypes (AMPA, NMDA, and kainite) mediate fast excitatory postsynaptic transmission, mGluRs are known to mediate slower excitatory postsynaptic responses and to be involved in synaptic plasticity in the mammalian brain. In addition to seven-transmembrane helices, the class C GPCRs are characterized by a large N-terminal extracellular Venus flytrap-like domain, which is composed of two adjacent lobes separated by a cleft which binds an endogenous ligand. Moreover, they exist as either homo- or heterodimers, which are essential for their function. For instance, mGluRs form homodimers via interactions between the N-terminal Venus flytrap domains and the intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD). At least eight different subtypes of metabotropic receptors (mGluR1-8) have been identified and further classified into three groups based on their sequence homology, pharmacological properties, and signaling pathways. Group 1 (mGluR1 and mGluR5) receptors are predominantly located postsynaptically on neurons and are involved in long-term synaptic plasticity in the brain, including long-term potentiation (LTP) in the hippocampus and long-term depression (LTD) in the cerebellum. They are coupled to G(q/11) proteins, thereby activating phospholipase C to generate inositol-1,4,5-triphosphate (IP3) and diacyglycerol (DAG), which in turn lead to Ca2+ release and protein kinase C activation, respectively. Group 1 mGluR expression is shown to be strongly upregulated in animal models of epilepsy, brain injury, inflammatory, and neuropathic pain, as well as in patients with amyotrophic lateral sclerosis or multiple sclerosis. Group 2 (mGluR2 and mGluR3) and 3 (mGluR4, mGluR6, mGluR7, and mGluR8) receptors are predominantly localized presynaptically in the active region of neurotransmitter release. They are coupled to G(i/o) proteins, which leads to inhibition of adenylate cyclase activity and cAMP formation, and consequently to a decrease in protein kinase A (PKA) activity. Ultimately, activation of these receptors leads to inhibition of neurotransmitter release such as glutamate and GABA via inhibition of Ca2+ channels and activation of K+ channels. Furthermore, while activation of Group 1 mGluRs increases NMDA (N-methyl-D-aspartate) receptor activity and risk of neurotoxicity, Group 2 and 3 mGluRs decrease NMDA receptor activity and prevent neurotoxicity.


Pssm-ID: 320564  Cd Length: 254  Bit Score: 58.04  E-value: 8.67e-09
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLR---NAETLGFGTAIHISFWNYWLLLFFIVGVQIALSIS 1148
Cdd:cd15448   52 YCMTFFFIAKPSPVICTLRRLGLGTSFAVCYSALLTKTNCIArifDGVKNGAQRPKFISPSSQVFICLSLILVQIVVVSV 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1149 WFLEPFMSTIGVIDTNVQR---MMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWVAW 1225
Cdd:cd15448  132 WLILEAPGTRRYTLPEKREtviLKCNVKDSSMLISLTYDVVLVILCTVYAFKTRKCPENFNEAKFIGFTMYTTCIIWLAF 211
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|..
gi 17540172 1226 ITLYLVLDHEFR--DTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15448  212 LPIFYVTSSDYRvqTTTMCISVSLSGFVVLGCLFAPKVHIIL 253
7tmC_RAIG3_GPRC5C cd15277
retinoic acid-inducible orphan G-protein-coupled receptor 3; class C family of ...
1072-1261 1.62e-08

retinoic acid-inducible orphan G-protein-coupled receptor 3; class C family of seven-transmembrane G protein-coupled receptors, group 5, member C; Retinoic acid-inducible G-protein-coupled receptors (RAIGs), also referred to as GPCR class C group 5, are a group consisting of four orphan receptors RAIG1 (GPRC5A), RAIG2 (GPRC5B), RAIG3 (GPRC5C), and RAIG4 (GPRC5D). Unlike other members of the class C GPCRs which contain a large N-terminal extracellular domain, RAIGs have a shorter N-terminus. Thus, it is unlikely that RAIGs bind an agonist at its N-terminus domain. Instead, the agonists may bind to the seven-transmembrane domain of these receptors. In addition, RAIG2 and RAIG3 contain a cleavable signal peptide whereas RAIG1 and RAIG4 do not. Although their expression is induced by retinoic acid (vitamin A analog), their biological function is not clearly understood. To date, no ligand is known for the members of RAIG family. Three receptor types (RAIG1-3) are found in vertebrates, while RAIG4 is only present in mammals. They show distinct tissue distribution with RAIG1 being primarily expressed in the lung, RAIG2 in the brain and placenta, RAIG3 in the brain, kidney and liver, and RAIG4 in the skin. The specific function of RAIG3 is unknown; however, this protein may play a role in mediating the effects of retinoic acid on embryogenesis, differentiation, and tumorigenesis through interaction with a G-protein signaling cascade.


Pssm-ID: 320404  Cd Length: 250  Bit Score: 57.05  E-value: 1.62e-08
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNaetlgfgTAIHISFWNYWLLLFFIVGVqialsisWFL 1151
Cdd:cd15277   54 FCLVFAFIVGPNFATCASRRFLFGVLFAICFSCLLAHAVRLNF-------LARRNRGPRGWVIFLLALGL-------WLV 119
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1152 EPFMSTIGVIDTNVQRMM---------CTMGKVEFVVSNFYVMILIFMALFIS--MLNRNIKRNYKETKWLLYSTVLCFF 1220
Cdd:cd15277  120 EVIINTEWLIITIVRGNAgsapvlgdpCNIANQDFVMALIYVMFLLLAAFITAwpALCGKYKHWRKHGAFILVTGFLSVA 199
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|....*.
gi 17540172 1221 TWVAWITLYL-----VLDHEFRDTVIVVELVACATILLGFLFGPKI 1261
Cdd:cd15277  200 IWVAWIVMYVygnqkVGQPYWDDPTLAIALVSNAWVFLFFYIIPEI 245
PBP1_mGluR cd06362
ligand binding domain of metabotropic glutamate receptors (mGluR); Ligand binding domain of ...
57-388 1.64e-08

ligand binding domain of metabotropic glutamate receptors (mGluR); Ligand binding domain of the metabotropic glutamate receptors (mGluR), which are members of the family C of G-protein-coupled receptors that transduce extracellular signals into G-protein activation and ultimately into cellular responses. mGluRs bind to glutamate and function as an excitatory neurotransmitter; they are involved in learning, memory, anxiety, and the perception of pain. Eight subtypes of mGluRs have been cloned so far, and are classified into three groups according to their sequence similarities, transduction mechanisms, and pharmacological profiles. Group I is composed of mGlu1R and mGlu5R that both stimulate PLC hydrolysis. Group II includes mGlu2R and mGlu3R, which inhibit adenylyl cyclase, as do mGlu4R, mGlu6R, mGlu7R, and mGlu8R, which form group III.


Pssm-ID: 380585 [Multi-domain]  Cd Length: 460  Bit Score: 58.84  E-value: 1.64e-08
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172   57 IGGSFPLH-----QDDCTTLRPDT-VQEIVAIQWALthwnqkDE-NGD------CKLGLYAGDTCSRSAESLSQSLRF-- 121
Cdd:cd06362    5 LGGLFPVHersssGECCGEIREERgIQRLEAMLFAI------DEiNSRpdllpnITLGFVILDDCSSDTTALEQALHFir 78
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  122 --LDSVGYHEPKECR-------TETPGAKLLGLIAPKDYESSMSLGKFLSVSAIPVAAYSSESVnaltELDVENT----I 188
Cdd:cd06362   79 dsLLSQESAGFCQCSddppnldESFQFYDVVGVIGAESSSVSIQVANLLRLFKIPQISYASTSD----ELSDKERypyfL 154
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  189 ATSPTIGVYVEALIRLINQMRSNLVTVV--DDGAQNPVVKKVISYLRDADIFVSESIPIDHPF--------LAQALEDSD 258
Cdd:cd06362  155 RTVPSDSFQAKAIVDILLHFNWTYVSVVysEGSYGEEGYKAFKKLARKAGICIAESERISQDSdekdyddvIQKLLQKKN 234
                        250       260       270       280       290       300       310       320
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  259 SSIVVSVLNK---QQLLKTVKHPSiYAMSKMWI---SIPTEGEALDESEqlellhkDAKLEVVSLQPKYKELPQFRDYFI 332
Cdd:cd06362  235 ARVVVLFADQediRGLLRAAKRLG-ASGRFIWLgsdGWGTNIDDLKGNE-------DVALGALTVQPYSEEVPRFDDYFK 306
                        330       340       350       360       370       380
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 17540172  333 RVLRNNFKNYQLLTSYIEQVYNC-----TNEDCNLNKDVMMKT--YVQARTAEASIRMTYAFA 388
Cdd:cd06362  307 SLTPSNNTRNPWFREFWQELFQCsfrpsRENSCNDDKLLINKSegYKQESKVSFVIDAVYAFA 369
PBP1_mGluR_groupII cd06375
ligand binding domain of the group II metabotropic glutamate receptor; Ligand binding domain ...
674-887 2.18e-08

ligand binding domain of the group II metabotropic glutamate receptor; Ligand binding domain of the group II metabotropic glutamate receptor, a family that contains mGlu2R and mGlu3R, all of which inhibit adenylyl cyclase. The metabotropic glutamate receptor is a member of the family C of G-protein-coupled receptors that transduce extracellular signals into G-protein activation and ultimately into intracellular responses. The mGluRs are classified into three groups which comprise eight subtypes


Pssm-ID: 380598 [Multi-domain]  Cd Length: 462  Bit Score: 58.30  E-value: 2.18e-08
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  674 QALALLKLLNRMQWQFVTAALSEQDPESLSLfRAFERLALDRGVCLAEVLNIGGSR----LDNI------RSTTNVTIVF 743
Cdd:cd06375  166 QAKAMAEILRFFNWTYVSTVASEGDYGETGI-EAFEQEARLRNICIATAEKVGRSAdrksFDGVirellqKPNARVVVLF 244
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  744 STARDAADYL------------IASKIRGNHVNVMMGEAHDWYlhapnnkelfpGTVSVQPRNILYGDFREWLETTTPLT 811
Cdd:cd06375  245 TRSDDARELLaaakrlnasftwVASDGWGAQESIVKGSEDVAE-----------GAITLELASHPIPDFDRYFQSLTPYN 313
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  812 L---PelWYWSYIESRYGCALSQKSKviygKMCTGDELLNIESLG--RMTKAGYLSRGVERFLFAMDSVYKSLCPAQNGL 886
Cdd:cd06375  314 NhrnP--WFRDFWEQKFQCSLQNKSQ----AASVSDKHLSIDSSNyeQESKIMFVVNAVYAMAHALHNMQRTLCPNTTRL 387

                 .
gi 17540172  887 C 887
Cdd:cd06375  388 C 388
ANF_receptor pfam01094
Receptor family ligand binding region; This family includes extracellular ligand binding ...
574-803 3.16e-08

Receptor family ligand binding region; This family includes extracellular ligand binding domains of a wide range of receptors. This family also includes the bacterial amino acid binding proteins of known structure.


Pssm-ID: 460062 [Multi-domain]  Cd Length: 347  Bit Score: 57.40  E-value: 3.16e-08
                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172    574 GLLKDLDFGALLIDSCSSGKQAIEsvvrsetQCFRFNQAGrnitivPKSVFG-----YASALHGDSQESLKGYFSSGDTD 648
Cdd:pfam01094   18 GLLPGTKLEYIILDTCCDPSLALA-------AALDLLKGE------VVAIIGpscssVASAVASLANEWKVPLISYGSTS 84
                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172    649 ASLvsvdsehSALQRS---FTALPSSRNQALALLKLLNRMQWQFVtAALSEQDPESLSLFRAFERLALDRGVCLAEVLNI 725
Cdd:pfam01094   85 PAL-------SDLNRYptfLRTTPSDTSQADAIVDILKHFGWKRV-ALIYSDDDYGESGLQALEDALRERGIRVAYKAVI 156
                          170       180       190       200       210       220       230       240
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172    726 GGSRLDN---------IRSTTNVTIVFSTARDAADYLIASKIRGnhvnvMMGEAHDWYL----------HAPNNKELFPG 786
Cdd:pfam01094  157 PPAQDDDeiarkllkeVKSRARVIVVCCSSETARRLLKAARELG-----MMGEGYVWIAtdglttslviLNPSTLEAAGG 231
                          250       260
                   ....*....|....*....|
gi 17540172    787 TVSVQ---PRNILYGDFREW 803
Cdd:pfam01094  232 VLGFRlhpPDSPEFSEFFWE 251
7tmC_TAS1R1 cd15289
type 1 taste receptor subtype 1, member of the class C of seven-transmembrane G ...
1082-1265 4.30e-08

type 1 taste receptor subtype 1, member of the class C of seven-transmembrane G protein-coupled receptors; This group represents TAS1R1, which is a member of the type I taste receptor (TAS1R) family that belongs to the class C of G protein-coupled receptors. The functional TAS1Rs are obligatory heterodimers built from three known members, TAS1R1-3. TAS1R1 combines with TAS1R3 to form an umami taste receptor, which is responsible for the perception of savory taste, such as the food additive mono-sodium glutamate (MSG); whereas the combination of TAS1R2-TAS1R3 forms a sweet-taste receptor for sugars and D-amino acids. On the other hand, the type II taste receptors (TAS2Rs), which belong to the class A family of GPCRs, recognize bitter tasting compounds. In the case of sweet, for example, the TAS1R2-TAS1R3 heterodimer activates phospholipase C (PLC) via alpha-gustducin, a heterodimeric G protein that is involved in perception of sweet and bitter tastes. This activation leads to generation of inositol (1, 4, 5)-trisphosphate (IP3) and diacylglycerol (DAG), and consequently increases intracellular Ca2+ mobilization and activates a cation channel, TRPM5. In contrast to the TAS1R2-TAS1R3 heterodimer, TAS1R3 alone could activate adenylate cyclase leading to cAMP formation in the absence of alpha-gustducin. Each TAS1R contains a large extracellular Venus flytrap-like domain in the N-terminus, cysteine-rich domain (CRD) and seven-transmembrane (7TM) domain, which are characteristics of the class C GPCRs. The Venus flytrap-like domain shares strong sequence homology to bacterial periplasmic binding proteins and possess the orthosteric amino acid and calcium binding sites for members of the class C, including CaSR, GABA-B1, GPRC6A, mGlu, and TAS1R receptors.


Pssm-ID: 320416  Cd Length: 253  Bit Score: 55.89  E-value: 4.30e-08
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1082 PTDSVCRLRVILHGLGYTICFGVMIAKATQLrnaeTLGFGTAIHI-SFWNYW-------LLLFFIVGVQIALSISWFL-- 1151
Cdd:cd15289   62 PTWLACLLKQPLFSLSFTVCLSCIAVRSFQI----VCIFKLASKLpRFYETWaknhgpeLFILISSAVQLLISLLWLVln 137
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1152 EPFMSTIGVIDTNVQRMMCT-MGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWVAWITLYL 1230
Cdd:cd15289  138 PPVPTKDYDRYPDLIVLECSqTLSVGSFLELLYNCLLSISCFVFSYMGKDLPANYNEAKCITFSLLIYFISWISFFTTYS 217
                        170       180       190
                 ....*....|....*....|....*....|....*...
gi 17540172 1231 VLDHEFrdtVIVVELVACATILLGFL---FGPKIYILL 1265
Cdd:cd15289  218 IYRGKY---LMAINVLAILSSLLGIFggyFLPKVYIIL 252
7tmC_mGluR_group2 cd15284
metabotropic glutamate receptors in group 2, member of the class C family of ...
1072-1265 8.98e-08

metabotropic glutamate receptors in group 2, member of the class C family of seven-transmembrane G protein-coupled receptors; The metabotropic glutamate receptors (mGluRs) in group 2 include mGluR 2 and 3. They are homodimeric class C G-protein coupled receptors which are activated by glutamate, the major excitatory neurotransmitter of the CNS. mGluRs are involved in regulating neuronal excitability and synaptic transmission via intracellular activation of second messenger signaling pathways. While the ionotropic glutamate receptor subtypes (AMPA, NMDA, and kainite) mediate fast excitatory postsynaptic transmission, mGluRs are known to mediate slower excitatory postsynaptic responses and to be involved in synaptic plasticity in the mammalian brain. In addition to seven-transmembrane helices, the class C GPCRs are characterized by a large N-terminal extracellular Venus flytrap-like domain, which is composed of two adjacent lobes separated by a cleft which binds an endogenous ligand. Moreover, they exist as either homo- or heterodimers, which are essential for their function. For instance, mGluRs form homodimers via interactions between the N-terminal Venus flytrap domains and the intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD). At least eight different subtypes of metabotropic receptors (mGluR1-8) have been identified and further classified into three groups based on their sequence homology, pharmacological properties, and signaling pathways. Group 1 (mGluR1 and mGluR5) receptors are predominantly located postsynaptically on neurons and are involved in long-term synaptic plasticity in the brain, including long-term potentiation (LTP) in the hippocampus and long-term depression (LTD) in the cerebellum. They are coupled to G(q/11) proteins, thereby activating phospholipase C to generate inositol-1,4,5-triphosphate (IP3) and diacyglycerol (DAG), which in turn lead to Ca2+ release and protein kinase C activation, respectively. Group 1 mGluR expression is shown to be strongly upregulated in animal models of epilepsy, brain injury, inflammatory, and neuropathic pain, as well as in patients with amyotrophic lateral sclerosis or multiple sclerosis. Group 2 (mGluR2 and mGluR3) and 3 (mGluR4, mGluR6, mGluR7, and mGluR8) receptors are predominantly localized presynaptically in the active region of neurotransmitter release. They are coupled to G(i/o) proteins, which leads to inhibition of adenylate cyclase activity and cAMP formation, and consequently to a decrease in protein kinase A (PKA) activity. Ultimately, activation of these receptors leads to inhibition of neurotransmitter release such as glutamate and GABA via inhibition of Ca2+ channels and activation of K+ channels. Furthermore, while activation of Group 1 mGluRs increases NMDA (N-methyl-D-aspartate) receptor activity and risk of neurotoxicity, Group 2 and 3 mGluRs decrease NMDA receptor activity and prevent neurotoxicity.


Pssm-ID: 320411  Cd Length: 254  Bit Score: 54.85  E-value: 8.98e-08
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLR---NAETLGFGTAIHISFWNYWLLLFFIVGVQIALSIS 1148
Cdd:cd15284   52 YCMTFIFIAKPSPAICTLRRLGLGTSFAVCYSALLTKTNRIArifSGVKDGAQRPRFISPSSQVFICLALISVQLLVVSV 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1149 WFLEPFMSTIGviDTNVQR-----MMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWV 1223
Cdd:cd15284  132 WLLVEAPGTRR--YTLPEKretviLKCNVRDSSMLISLTYDVVLVILCTVYAFKTRKCPENFNEAKFIGFTMYTTCIIWL 209
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|....
gi 17540172 1224 AWITLYLVLDHEFR--DTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15284  210 AFLPIFYVTSSDYRvqTTTMCISVSLSGFVVLGCLFAPKVHIIL 253
7tmC_RAIG1_4_GPRC5A_D cd15279
retinoic acid-inducible orphan G-protein-coupled receptors 1 and 4; class C family of ...
1075-1264 9.94e-08

retinoic acid-inducible orphan G-protein-coupled receptors 1 and 4; class C family of seven-transmembrane G protein-coupled receptors, group 5, member A and D; Retinoic acid-inducible G-protein-coupled receptors (RAIGs), also referred to as GPCR class C group 5, are a group consisting of four orphan receptors RAIG1 (GPRC5A), RAIG2 (GPRC5B), RAIG3 (GPRC5C), and RAIG4 (GPRC5D). Unlike other members of the class C GPCRs which contain a large N-terminal extracellular domain, RAIGs have a shorter N-terminus. Thus, it is unlikely that RAIGs bind an agonist at its N-terminus domain. Instead, the agonists may bind to the seven-transmembrane domain of these receptors. In addition, RAIG2 and RAIG3 contain a cleavable signal peptide whereas RAIG1 and RAIG4 do not. Although their expression is induced by retinoic acid (vitamin A analog), their biological function is not clearly understood. To date, no ligand is known for the members of RAIG family. Three receptor types (RAIG1-3) are found in vertebrates, while RAIG4 is only present in mammals. They show distinct tissue distribution with RAIG1 being primarily expressed in the lung, RAIG2 in the brain and placenta, RAIG3 in the brain, kidney and liver, and RAIG4 in the skin. RAIG1 is evolutionarily conserved from mammals to fish. RAIG1 has been to shown to act as a tumor suppressor in non-small cell lung carcinoma as well as oral squamous cell carcinoma, but it could also act as an oncogene in breast cancer, colorectal cancer, and pancreatic cancer. Studies have shown that overexpression of RAIG1 decreases intracellular cAMP levels. Moreover, knocking out RAIG1 induces the activation of the NF-kB and STAT3 signaling pathways leading to cell proliferation and resistance to apoptosis. The specific function of RAIG4 is unknown; however, this protein may play a role in mediating the effects of retinoic acid on embryogenesis, differentiation, and tumorigenesis through interaction with a G-protein signaling cascade.


Pssm-ID: 320406  Cd Length: 248  Bit Score: 54.77  E-value: 9.94e-08
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1075 AFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFGtaihISFWNYWLLLFFIVGVQIALSISWFLepF 1154
Cdd:cd15279   57 TFAFIIELNGQTGPTRFFLFGVLFAICFSCLLAHASNLVKLVRGRKP----FSWLVILLLAVGFSLVQVVIAIEYIV--L 130
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1155 MSTIGVIDTNVQRMMCTMGKvEFVVSNFYVMILIFMALFISMLNR-NIKRNYKETKWLLYSTVL-CFFTWVAWITLYLV- 1231
Cdd:cd15279  131 TMVRTNVNVFSEMTAPQLNE-DFVLLLIYVLFLMALTFLVSKFTFcGSCKGWKRHGAHIFVTMLfSIAIWVAWITMLLRg 209
                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 17540172 1232 ----LDHEFRDTVIVVELVACATILLGFLFGPKIYIL 1264
Cdd:cd15279  210 npfqRNRQWDDPVLSIALVANGWVFLLMYIVPELCLL 246
7tmC_mGluR_group3 cd15286
metabotropic glutamate receptors in group 3, member of the class C family of ...
1072-1265 4.94e-07

metabotropic glutamate receptors in group 3, member of the class C family of seven-transmembrane G protein-coupled receptors; The metabotropic glutamate receptors (mGluRs) in group 3 include mGluRs 4, 6, 7, and 8. They are homodimeric class C G-protein coupled receptors which are activated by glutamate, the major excitatory neurotransmitter of the CNS. mGluRs are involved in regulating neuronal excitability and synaptic transmission via intracellular activation of second messenger signaling pathways. While the ionotropic glutamate receptor subtypes (AMPA, NMDA, and kainite) mediate fast excitatory postsynaptic transmission, mGluRs are known to mediate slower excitatory postsynaptic responses and to be involved in synaptic plasticity in the mammalian brain. In addition to seven-transmembrane helices, the class C GPCRs are characterized by a large N-terminal extracellular Venus flytrap-like domain, which is composed of two adjacent lobes separated by a cleft which binds an endogenous ligand. Moreover, they exist as either homo- or heterodimers, which are essential for their function. For instance, mGluRs form homodimers via interactions between the N-terminal Venus flytrap domains and the intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD). At least eight different subtypes of metabotropic receptors (mGluR1-8) have been identified and further classified into three groups based on their sequence homology, pharmacological properties, and signaling pathways. Group 1 (mGluR1 and mGluR5) receptors are predominantly located postsynaptically on neurons and are involved in long-term synaptic plasticity in the brain, including long-term potentiation (LTP) in the hippocampus and long-term depression (LTD) in the cerebellum. They are coupled to G(q/11) proteins, thereby activating phospholipase C to generate inositol-1,4,5-triphosphate (IP3) and diacyglycerol (DAG), which in turn lead to Ca2+ release and protein kinase C activation, respectively. Group 1 mGluR expression is shown to be strongly upregulated in animal models of epilepsy, brain injury, inflammatory, and neuropathic pain, as well as in patients with amyotrophic lateral sclerosis or multiple sclerosis. Group 2 (mGluR2 and mGluR3) and 3 (mGluR4, mGluR6, mGluR7, and mGluR8) receptors are predominantly localized presynaptically in the active region of neurotransmitter release. They are coupled to G(i/o) proteins, which leads to inhibition of adenylate cyclase activity and cAMP formation, and consequently to a decrease in protein kinase A (PKA) activity. Ultimately, activation of these receptors leads to inhibition of neurotransmitter release such as glutamate and GABA via inhibition of Ca2+ channels and activation of K+ channels. Furthermore, while activation of Group 1 mGluRs increases NMDA (N-methyl-D-aspartate) receptor activity and risk of neurotoxicity, Group 2 and 3 mGluRs decrease NMDA receptor activity and prevent neurotoxicity.


Pssm-ID: 320413  Cd Length: 271  Bit Score: 52.88  E-value: 4.94e-07
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFGTAI---HISFWNYWLLLFFIVGVQIALSIS 1148
Cdd:cd15286   52 YAITFLMVAEPGVGVCSLRRLFLGLGMSLSYAALLTKTNRIYRIFEQGKKSVTpprFISPTSQLVITFSLISVQLLGVLA 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1149 WFL-EPFMStigVIDTNVQRMM----------CTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETK---WLLYS 1214
Cdd:cd15286  132 WFAvDPPHA---LIDYEEGRTPdpeqargvlrCDMSDLSLICCLGYSLLLMVTCTVYAIKARGVPETFNEAKpigFTMYT 208
                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 17540172 1215 TVLcffTWVAWITLYL-----VLDHEFRDTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15286  209 TCI---VWLAFIPIFFgtaqsAEKLYIQTATLTVSMSLSASVSLGMLYMPKVYVIL 261
7tmC_mGluR8 cd15454
metabotropic glutamate receptor 8 in group 3, member of the class C family of ...
1072-1265 7.67e-07

metabotropic glutamate receptor 8 in group 3, member of the class C family of seven-transmembrane G protein-coupled receptors; The receptors in group 3 include mGluRs 4, 6, 7, and 8. They are homodimeric class C G-protein coupled receptors which are activated by glutamate, the major excitatory neurotransmitter of the CNS. mGluRs are involved in regulating neuronal excitability and synaptic transmission via intracellular activation of second messenger signaling pathways. While the ionotropic glutamate receptor subtypes (AMPA, NMDA, and kainite) mediate fast excitatory postsynaptic transmission, mGluRs are known to mediate slower excitatory postsynaptic responses and to be involved in synaptic plasticity in the mammalian brain. In addition to seven-transmembrane helices, the class C GPCRs are characterized by a large N-terminal extracellular Venus flytrap-like domain, which is composed of two adjacent lobes separated by a cleft which binds an endogenous ligand. Moreover, they exist as either homo- or heterodimers, which are essential for their function. For instance, mGluRs form homodimers via interactions between the N-terminal Venus flytrap domains and the intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD). At least eight different subtypes of metabotropic receptors (mGluR1-8) have been identified and further classified into three groups based on their sequence homology, pharmacological properties, and signaling pathways. Group 1 (mGluR1 and mGluR5) receptors are predominantly located postsynaptically on neurons and are involved in long-term synaptic plasticity in the brain, including long-term potentiation (LTP) in the hippocampus and long-term depression (LTD) in the cerebellum. They are coupled to G(q/11) proteins, thereby activating phospholipase C to generate inositol-1,4,5-triphosphate (IP3) and diacyglycerol (DAG), which in turn lead to Ca2+ release and protein kinase C activation, respectively. Group 1 mGluR expression is shown to be strongly upregulated in animal models of epilepsy, brain injury, inflammatory, and neuropathic pain, as well as in patients with amyotrophic lateral sclerosis or multiple sclerosis. Group 2 (mGluR2 and mGluR3) and 3 (mGluR4, mGluR6, mGluR7, and mGluR8) receptors are predominantly localized presynaptically in the active region of neurotransmitter release. They are coupled to G(i/o) proteins, which leads to inhibition of adenylate cyclase activity and cAMP formation, and consequently to a decrease in protein kinase A (PKA) activity. Ultimately, activation of these receptors leads to inhibition of neurotransmitter release such as glutamate and GABA via inhibition of Ca2+ channels and activation of K+ channels. Furthermore, while activation of Group 1 mGluRs increases NMDA (N-methyl-D-aspartate) receptor activity and risk of neurotoxicity, Group 2 and 3 mGluRs decrease NMDA receptor activity and prevent neurotoxicity.


Pssm-ID: 320570 [Multi-domain]  Cd Length: 311  Bit Score: 52.71  E-value: 7.67e-07
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFGTAI---HISFWNYWLLLFFIVGVQIALSIS 1148
Cdd:cd15454   52 YAITFLMIATPDTGICSFRRVFLGLGMCFSYAALLTKTNRIHRIFEQGKKSVTapkFISPASQLVITFSLISVQLLGVFV 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1149 WFLEPFMSTIgvIDTNVQR----------MMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLC 1218
Cdd:cd15454  132 WFAVDPPHTI--VDYGEQRtldpekargvLKCDISDLSLICSLGYSILLMVTCTVYAIKTRGVPETFNEAKPIGFTMYTT 209
                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|..
gi 17540172 1219 FFTWVAWITLYLVLDHE-----FRDTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15454  210 CIIWLAFIPIFFGTAQSaermyIQTTTLTISMSLSASVSLGMLYMPKVYIII 261
7tmC_mGluR7 cd15451
metabotropic glutamate receptor 7 in group 3, member of the class C family of ...
1072-1279 3.84e-06

metabotropic glutamate receptor 7 in group 3, member of the class C family of seven-transmembrane G protein-coupled receptors; The receptors in group 3 include mGluRs 4, 6, 7, and 8. They are homodimeric class C G-protein coupled receptors which are activated by glutamate, the major excitatory neurotransmitter of the CNS. mGluRs are involved in regulating neuronal excitability and synaptic transmission via intracellular activation of second messenger signaling pathways. While the ionotropic glutamate receptor subtypes (AMPA, NMDA, and kainite) mediate fast excitatory postsynaptic transmission, mGluRs are known to mediate slower excitatory postsynaptic responses and to be involved in synaptic plasticity in the mammalian brain. In addition to seven-transmembrane helices, the class C GPCRs are characterized by a large N-terminal extracellular Venus flytrap-like domain, which is composed of two adjacent lobes separated by a cleft which binds an endogenous ligand. Moreover, they exist as either homo- or heterodimers, which are essential for their function. For instance, mGluRs form homodimers via interactions between the N-terminal Venus flytrap domains and the intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD). At least eight different subtypes of metabotropic receptors (mGluR1-8) have been identified and further classified into three groups based on their sequence homology, pharmacological properties, and signaling pathways. Group 1 (mGluR1 and mGluR5) receptors are predominantly located postsynaptically on neurons and are involved in long-term synaptic plasticity in the brain, including long-term potentiation (LTP) in the hippocampus and long-term depression (LTD) in the cerebellum. They are coupled to G(q/11) proteins, thereby activating phospholipase C to generate inositol-1,4,5-triphosphate (IP3) and diacyglycerol (DAG), which in turn lead to Ca2+ release and protein kinase C activation, respectively. Group 1 mGluR expression is shown to be strongly upregulated in animal models of epilepsy, brain injury, inflammatory, and neuropathic pain, as well as in patients with amyotrophic lateral sclerosis or multiple sclerosis. Group 2 (mGluR2 and mGluR3) and 3 (mGluR4, mGluR6, mGluR7, and mGluR8) receptors are predominantly localized presynaptically in the active region of neurotransmitter release. They are coupled to G(i/o) proteins, which leads to inhibition of adenylate cyclase activity and cAMP formation, and consequently to a decrease in protein kinase A (PKA) activity. Ultimately, activation of these receptors leads to inhibition of neurotransmitter release such as glutamate and GABA via inhibition of Ca2+ channels and activation of K+ channels. Furthermore, while activation of Group 1 mGluRs increases NMDA (N-methyl-D-aspartate) receptor activity and risk of neurotoxicity, Group 2 and 3 mGluRs decrease NMDA receptor activity and prevent neurotoxicity.


Pssm-ID: 320567  Cd Length: 307  Bit Score: 50.41  E-value: 3.84e-06
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLRNAETLGFGTAIH---ISFWNYWLLLFFIVGVQIALSIS 1148
Cdd:cd15451   52 YIITFLMIAKPDVAVCSFRRIFLGLGMCISYAALLTKTNRIYRIFEQGKKSVTAprlISPTSQLAITSSLISVQLLGVLI 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1149 WFLEPFMSTIgvIDTNVQRMM----------CTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLC 1218
Cdd:cd15451  132 WFAVDPPNII--IDYDEQKTMnpeqargvlkCDITDLQIICSLGYSILLMVTCTVYAIKTRGVPENFNEAKPIGFTMYTT 209
                        170       180       190       200       210       220
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 17540172 1219 FFTWVAWITLYLVLDHE-----FRDTVIVVELVACATILLGFLFGPKIYILLSYEPVVVAFKRDPF 1279
Cdd:cd15451  210 CIVWLAFIPIFFGTAQSaeklyIQTTTLTISMNLSASVALGMLYMPKVYIIIFHPELNVQKRKRSF 275
7tmC_GPR158-like cd15293
orphan GPR158 and similar proteins, member of the class C family of seven-transmembrane G ...
1072-1265 1.23e-04

orphan GPR158 and similar proteins, member of the class C family of seven-transmembrane G protein-coupled receptors; This group includes orphan receptors GPR158, GPR158-like (also called GPR179) and similar proteins. These orphan receptors are closely related to the type B receptor for gamma-aminobutyric acid (GABA-B), which is activated by its endogenous ligand GABA, the principal inhibitory neurotransmitter. The functional GABA-B receptor is an obligatory heterodimer composed of two related subunits, GABA-B1, which is primarily involved in GABA ligand binding, and GABA-B2, which is responsible for both G-protein coupling and trafficking of the heterodimer to the plasma membrane. Activation of GABA-B couples to G(i/o)-type G proteins, which in turn modulate three major downstream effectors: adenylate cyclase, voltage-sensitive Ca2+ channels, and inwardly-rectifying K+ channels. Consequently, GABA-B receptor produces slow and sustained inhibitory responses by decreased neurotransmitter release via inhibition of Ca2+ channels and by postsynaptic hyperpolarization via the activation of K+ channels through the G-protein beta-gamma dimer. The GABA-B is expressed in both pre- and postsynaptic sites of glutamatergic and GABAergic neurons in the brain where it regulates synaptic activity. Thus, the GABA-B receptor agonist, baclofen, is used to treat muscle tightness and cramping caused by spasticity in multiple sclerosis patients. Moreover, GABA-B antagonists improves cognitive performance in mammals, while GABA-B agonists suppress cognitive behavior. In most of the class C family members, the extracellular Venus-flytrap domain in the N-terminus is connected to the seven-transmembrane (7TM) via a cysteine-rich domain (CRD). However, in the GABA-B receptor, the CRD is absent in both subunits and the Venus-flytrap ligand-binding domain is directly connected to the 7TM via a 10-15 amino acids linker, suggesting that GABA-B receptor may utilize a different activation mechanism.


Pssm-ID: 320420  Cd Length: 252  Bit Score: 45.28  E-value: 1.23e-04
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKAtqLRNAETLGFGTA--IHISFWNYWLLLFFIVGVQIALSISW 1149
Cdd:cd15293   52 YFPVFILYFEPSVFRCILRPWFRHLGFAIVYGALILKT--YRILVVFRSRSArrVHLTDRDLLKRLGLIVLVVLGYLAAW 129
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1150 F---LEPFMSTIGVIDTNVQRMMCTMGKVEFVvsnFYVMILIFMA--LFISMLNRNIKRNYKETK--------WLLYSTV 1216
Cdd:cd15293  130 TavnPPNVEVGLTLTSSGLKFNVCSLDWWDYV---MAIAELLFLLwgVYLCYAVRKAPSAFNESRyislaiynELLLSVI 206
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|....*....
gi 17540172 1217 LCFFTWVAWITLYlvLDHEFrdTVIVVELVACATILLGFLFGPKIYILL 1265
Cdd:cd15293  207 FNIIRFFLLPSLH--PDLLF--LLFFLHTQLTVTVTLLLIFGPKFYLVL 251
7tmC_mGluR5 cd15450
metabotropic glutamate receptor 5 in group 1, member of the class C family of ...
1072-1266 1.54e-04

metabotropic glutamate receptor 5 in group 1, member of the class C family of seven-transmembrane G protein-coupled receptors; Group 1 mGluRs includes mGluR1 and mGluR5, as well as their closely related invertebrate receptors. They are homodimeric class C G-protein coupled receptors which are activated by glutamate, the major excitatory neurotransmitter of the CNS. mGluRs are involved in regulating neuronal excitability and synaptic transmission via intracellular activation of second messenger signaling pathways. While the ionotropic glutamate receptor subtypes (AMPA, NMDA, and kainite) mediate fast excitatory postsynaptic transmission, mGluRs are known to mediate slower excitatory postsynaptic responses and to be involved in synaptic plasticity in the mammalian brain. In addition to seven-transmembrane helices, the class C GPCRs are characterized by a large N-terminal extracellular Venus flytrap-like domain, which is composed of two adjacent lobes separated by a cleft which binds an endogenous ligand. Moreover, they exist as either homo- or heterodimers, which are essential for their function. For instance, mGluRs form homodimers via interactions between the N-terminal Venus flytrap domains and the intermolecular disulphide bonds between cysteine residues located in the cysteine-rich domain (CRD). At least eight different subtypes of metabotropic receptors (mGluR1-8) have been identified and further classified into three groups based on their sequence homology, pharmacological properties, and signaling pathways. Group 1 (mGluR1 and mGluR5) receptors are predominantly located postsynaptically on neurons and are involved in long-term synaptic plasticity in the brain, including long-term potentiation (LTP) in the hippocampus and long-term depression (LTD) in the cerebellum. They are coupled to G(q/11) proteins, thereby activating phospholipase C to generate inositol-1,4,5-triphosphate (IP3) and diacyglycerol (DAG), which in turn lead to Ca2+ release and protein kinase C activation, respectively. Group 1 mGluR expression is shown to be strongly upregulated in animal models of epilepsy, brain injury, inflammatory, and neuropathic pain, as well as in patients with amyotrophic lateral sclerosis or multiple sclerosis. Group 2 (mGluR2 and mGluR3) and 3 (mGluR4, mGluR6, mGluR7, and mGluR8) receptors are predominantly localized presynaptically in the active region of neurotransmitter release. They are coupled to G(i/o) proteins, which leads to inhibition of adenylate cyclase activity and cAMP formation, and consequently to a decrease in protein kinase A (PKA) activity. Ultimately, activation of these receptors leads to inhibition of neurotransmitter release such as glutamate and GABA via inhibition of Ca2+ channels and activation of K+ channels. Furthermore, while activation of Group 1 mGluRs increases NMDA (N-methyl-D-aspartate) receptor activity and risk of neurotoxicity, Group 2 and 3 mGluRs decrease NMDA receptor activity and prevent neurotoxicity.


Pssm-ID: 320566  Cd Length: 250  Bit Score: 44.98  E-value: 1.54e-04
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1072 YSTAFFFVFDPTDSVCRLRVILHGLGYTICFGVMIAKATQLR-----NAETLGFGTAIHISFWNYWLLLFFIVGVQIALS 1146
Cdd:cd15450   52 YLCTFCLIAKPKQIYCYLQRIGIGLSPAMSYSALVTKTNRIArilagSKKKICTKKPRFMSACAQLVIAFILICIQLGII 131
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172 1147 ISWF-LEPFMSTIGVIDTNVQRMMCTMGKVEFVVSNFYVMILIFMALFISMLNRNIKRNYKETKWLLYSTVLCFFTWVAW 1225
Cdd:cd15450  132 VALFiMEPPDIMHDYPSIREVYLICNTTNLGVVTPLGYNGLLILSCTFYAFKTRNVPANFNEAKYIAFTMYTTCIIWLAF 211
                        170       180       190       200
                 ....*....|....*....|....*....|....*....|.
gi 17540172 1226 ITLYLVLDHEFRDTVIVVELvaCATILLGFLFGPKIYILLS 1266
Cdd:cd15450  212 VPIYFGSNYKIITMCFSVSL--SATVALGCMFVPKVYIILA 250
PBP1_CaSR cd06364
ligand-binding domain of the CaSR calcium-sensing receptor, a member of the family C receptors ...
665-852 4.78e-04

ligand-binding domain of the CaSR calcium-sensing receptor, a member of the family C receptors within the G-protein coupled receptor superfamily; Ligand-binding domain of the CaSR calcium-sensing receptor, which is a member of the family C receptors within the G-protein coupled receptor superfamily. CaSR provides feedback control of extracellular calcium homeostasis by responding sensitively to acute fluctuations in extracellular ionized Ca2+ concentration. This ligand-binding domain has homology to the bacterial leucine-isoleucine-valine binding protein (LIVBP) and a leucine binding protein (LBP). CaSR is widely expressed in mammalian tissues and is active in tissues that are not directly involved in extracellular calcium homeostasis. Moreover, CaSR responds to aromatic, aliphatic, and polar amino acids, but not to positively charged or branched chain amino acids, which suggests that changes in plasma amino acid levels are likely to modulate whole body calcium metabolism. Additionally, the family C GPCRs includes at least two receptors with broad-spectrum amino acid-sensing properties: GPRC6A which recognizes basic and various aliphatic amino acids, its gold-fish homolog the 5.24 chemoreceptor, and a specific taste receptor (T1R) which responds to aliphatic, polar, charged, and branched amino acids, but not to aromatic amino acids.


Pssm-ID: 380587 [Multi-domain]  Cd Length: 473  Bit Score: 44.55  E-value: 4.78e-04
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  665 FTALPSSRNQALALLKLLNRMQWQFVTAALSEQDpESLSLFRAFERLALDRGVCLAEVLNIggSRLDN---IR------- 734
Cdd:cd06364  147 LRTIPSDYYQSRALAQLVKHFGWTWVGAIASDDD-YGRNGIKAFLEEAEKLGICIAFSETI--PRTYSqekILrivevik 223
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  735 -STTNVTIVFSTARDaADYLIASKIRGNhvnvMMG------EAhdW----YLHAPNNKELFPGTVSVQPRNILYGDFREW 803
Cdd:cd06364  224 kSTAKVIVVFSSEGD-LEPLIKELVRQN----ITGrqwiasEA--WitssLLATPEYFPVLGGTIGFAIRRGEIPGLKEF 296
                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 17540172  804 LETTTPLTLP------ELWywsyiESRYGCALSQKSKVI----YGKMCTGDEllNIESL 852
Cdd:cd06364  297 LLRVHPSKSPsnpfvkEFW-----EETFNCSLSSSSKSNssssSRPPCTGSE--NLENV 348
PBP1_taste_receptor cd06363
ligand-binding domain of the T1R taste receptor; Ligand-binding domain of the T1R taste ...
55-248 1.29e-03

ligand-binding domain of the T1R taste receptor; Ligand-binding domain of the T1R taste receptor. The T1R is a member of the family C receptors within the G-protein coupled receptor superfamily, which also includes the metabotropic glutamate receptors, GABAb receptors, the calcium-sensing receptor (CaSR), the V2R pheromone receptors, and a small group of uncharacterized orphan receptors.


Pssm-ID: 380586 [Multi-domain]  Cd Length: 418  Bit Score: 43.06  E-value: 1.29e-03
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172   55 FQIGGSFPLHQDD--------------CTTLRPD----------TVQEIVaiqwalthwNQKDENGDCKLGLYAGDTCSR 110
Cdd:cd06363    7 YLLGGLFPLHELTstlphrppeptdcsCDRFNLHgyhlaqamrfAVEEIN---------NSSDLLPGVTLGYEIFDTCSD 77
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172  111 SAeSLSQSLRFLDSVGYHE-PKECRTETPGAKLLGLIAPKDYESSMSLGKFLSVSAIPVAAYSSESVnaltELDVENT-- 187
Cdd:cd06363   78 AV-NFRPTLSFLSQNGSHDiEVQCNYTNYQPRVVAVIGPDSSELALTTAKLLGFFLMPQISYGASSE----ELSNKLLyp 152
                        170       180       190       200       210       220
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 17540172  188 --IATSPTIGVYVEALIRLINQMRSNLVTVV--DD--GAQNpvVKKVISYLRDADIFVS--ESIPIDHP 248
Cdd:cd06363  153 sfLRTVPSDKYQVEAMVQLLQEFGWNWVAFLgsDDeyGQDG--LQLFSEKAANTGICVAyqGLIPTDTD 219
PBP1_mGluR_groupII cd06375
ligand binding domain of the group II metabotropic glutamate receptor; Ligand binding domain ...
57-175 1.73e-03

ligand binding domain of the group II metabotropic glutamate receptor; Ligand binding domain of the group II metabotropic glutamate receptor, a family that contains mGlu2R and mGlu3R, all of which inhibit adenylyl cyclase. The metabotropic glutamate receptor is a member of the family C of G-protein-coupled receptors that transduce extracellular signals into G-protein activation and ultimately into intracellular responses. The mGluRs are classified into three groups which comprise eight subtypes


Pssm-ID: 380598 [Multi-domain]  Cd Length: 462  Bit Score: 42.50  E-value: 1.73e-03
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172   57 IGGSFPLHQ-----DDCTTLRPDT-VQEIVAIQWALTHWNQkDEN--GDCKLGLYAGDTCSRSAESLSQSLRF------- 121
Cdd:cd06375    9 LGGLFPVHEkgegmEECGRINEDRgIQRLEAMLFAIDRINR-DPHllPGVRLGVHILDTCSRDTYALEQSLEFvrasltk 87
                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|....*...
gi 17540172  122 LDSVGYH----EPKECRTETPGAkLLGLIAPKDYESSMSLGKFLSVSAIPVAAYSSES 175
Cdd:cd06375   88 VDDSEYMcpddGSYAIQEDSPLP-IAGVIGGSYSSVSIQVANLLRLFQIPQISYASTS 144
ANF_receptor pfam01094
Receptor family ligand binding region; This family includes extracellular ligand binding ...
81-354 3.20e-03

Receptor family ligand binding region; This family includes extracellular ligand binding domains of a wide range of receptors. This family also includes the bacterial amino acid binding proteins of known structure.


Pssm-ID: 460062 [Multi-domain]  Cd Length: 347  Bit Score: 41.60  E-value: 3.20e-03
                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172     81 AIQWALTHWNQKDE-NGDCKLGLYAGDTCSRSAESLSQSLRFLDsvgyhepkecrtetpgAKLLGLIAPKDYESSMSLGK 159
Cdd:pfam01094    5 AVRLAVEDINADPGlLPGTKLEYIILDTCCDPSLALAAALDLLK----------------GEVVAIIGPSCSSVASAVAS 68
                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172    160 FLSVSAIPVAAYSSESvNALTELDVENTIA-TSPTIGVYVEALIRLINQMRSNLVTVV----DDGaqNPVVKKVISYLRD 234
Cdd:pfam01094   69 LANEWKVPLISYGSTS-PALSDLNRYPTFLrTTPSDTSQADAIVDILKHFGWKRVALIysddDYG--ESGLQALEDALRE 145
                          170       180       190       200       210       220       230       240
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 17540172    235 ADIFV--SESIP--IDHPFLAQALE---DSDSSIVV---SVLNKQQLLKTVKHPSIYAMSKMWISIPTEGEALDESEQLE 304
Cdd:pfam01094  146 RGIRVayKAVIPpaQDDDEIARKLLkevKSRARVIVvccSSETARRLLKAARELGMMGEGYVWIATDGLTTSLVILNPST 225
                          250       260       270       280       290
                   ....*....|....*....|....*....|....*....|....*....|.
gi 17540172    305 LLHKDAKLEVVSLQPKYKELPQFRDYFIRVLRNNFKNYQLLT-SYIEQVYN 354
Cdd:pfam01094  226 LEAAGGVLGFRLHPPDSPEFSEFFWEKLSDEKELYENLGGLPvSYGALAYD 276
 
Blast search parameters
Data Source: Precalculated data, version = cdd.v.3.21
Preset Options:Database: CDSEARCH/cdd   Low complexity filter: no  Composition Based Adjustment: yes   E-value threshold: 0.01

References:

  • Wang J et al. (2023), "The conserved domain database in 2023", Nucleic Acids Res.51(D)384-8.
  • Lu S et al. (2020), "The conserved domain database in 2020", Nucleic Acids Res.48(D)265-8.
  • Marchler-Bauer A et al. (2017), "CDD/SPARCLE: functional classification of proteins via subfamily domain architectures.", Nucleic Acids Res.45(D)200-3.
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