C2 domain second repeat present in Synaptotagmin; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. There are several classes of Synaptotagmins. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the second C2 repeat, C2B, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204  96 GDILFSVSYLPTAERLTVVVLKARNLKTMDINGSSDPFVKVSLLQGGRRVKKKKTSVRKCNCNPTWNEAIIFNVPAAALN 175
Cdd:cd00276     1 GELLLSLSYLPTAERLTVVVLKARNLPPSDGKGLSDPYVKVSLLQGGKKLKKKKTSVKKGTLNPVFNEAFSFDVPAEQLE 80

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1752368204 176 ACSLELIVMDYDLLGQCEKIGETVVGPHSGGLGQDQWTEMVQTPRKPVSVWHTL 229
Cdd:cd00276    81 EVSLVITVVDKDSVGRNEVIGQVVLGPDSGGEELEHWNEMLASPRKPIARWHKL 134

C2 domain second repeat present in Synaptotagmin; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. There are several classes of Synaptotagmins. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the second C2 repeat, C2B, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204  96 GDILFSVSYLPTAERLTVVVLKARNLKTMDINGSSDPFVKVSLLQGGRRVKKKKTSVRKCNCNPTWNEAIIFNVPAAALN 175
Cdd:cd00276     1 GELLLSLSYLPTAERLTVVVLKARNLPPSDGKGLSDPYVKVSLLQGGKKLKKKKTSVKKGTLNPVFNEAFSFDVPAEQLE 80

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1752368204 176 ACSLELIVMDYDLLGQCEKIGETVVGPHSGGLGQDQWTEMVQTPRKPVSVWHTL 229
Cdd:cd00276    81 EVSLVITVVDKDSVGRNEVIGQVVLGPDSGGEELEHWNEMLASPRKPIARWHKL 134

C2 domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204 110 RLTVVVLKARNLKTMDINGSSDPFVKVSLLQGgrrVKKKKTSVRKCNCNPTWNEAIIFNVPaaALNACSLELIVMDYDLL 189
Cdd:pfam00168   2 RLTVTVIEAKNLPPKDGNGTSDPYVKVYLLDG---KQKKKTKVVKNTLNPVWNETFTFSVP--DPENAVLEIEVYDYDRF 76

                          90       100
                  ....*....|....*....|....*...
gi 1752368204 190 GQCEKIGETV--VGPHSGGLGQDQWTEM 215
Cdd:pfam00168  77 GRDDFIGEVRipLSELDSGEGLDGWYPL 104

C2 domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204   1 MDIGVSSDPYVKISLEPDEERK----IKQSV--VQNEIFKFPttYEELQEKTVRFSVFDFDKFSRHDAIGEVLVRINDVD 74
Cdd:pfam00168  16 KDGNGTSDPYVKVYLLDGKQKKktkvVKNTLnpVWNETFTFS--VPDPENAVLEIEVYDYDRFGRDDFIGEVRIPLSELD 93

                          90
                  ....*....|.
gi 1752368204  75 VSRELDVWSEL 85
Cdd:pfam00168  94 SGEGLDGWYPL 104

Ca2+-dependent lipid-binding protein, contains C2 domain [General function prediction only];

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204   61 DAIGEVLVRINDVdVSRELDVWSELRSPQSRKEELgdilfSVSYLPTAER------------LTVVVLKARNLKTMDING 128
Cdd:COG5038    986 KVVCEVTLPTLDL-VSNAYEKPSSLNFPGSAKVLV-----QVSYTPVPVKlppvemvensgyLTIMLRSGENLPSSDENG 1059

                           90       100       110       120       130       140       150
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1752368204  129 SSDPFVKVSLlqGGRRVKKKKtsVRKCNCNPTWNEAIIFNVPAAALNAcsLELIVMDYD------LLGQCE 193
Cdd:COG5038   1060 YSDPFVKLFL--NEKSVYKTK--VVKKTLNPVWNEEFTIEVLNRVKDV--LTINVNDWDsgekndLLGTAE 1124

C2 domain second repeat present in Synaptotagmin; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. There are several classes of Synaptotagmins. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the second C2 repeat, C2B, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204  96 GDILFSVSYLPTAERLTVVVLKARNLKTMDINGSSDPFVKVSLLQGGRRVKKKKTSVRKCNCNPTWNEAIIFNVPAAALN 175
Cdd:cd00276     1 GELLLSLSYLPTAERLTVVVLKARNLPPSDGKGLSDPYVKVSLLQGGKKLKKKKTSVKKGTLNPVFNEAFSFDVPAEQLE 80

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1752368204 176 ACSLELIVMDYDLLGQCEKIGETVVGPHSGGLGQDQWTEMVQTPRKPVSVWHTL 229
Cdd:cd00276    81 EVSLVITVVDKDSVGRNEVIGQVVLGPDSGGEELEHWNEMLASPRKPIARWHKL 134

C2 domain second repeat present in Synaptotagmin 7; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. Synaptotagmin 7, a member of class 2 synaptotagmins, is located in presynaptic plasma membranes in neurons, dense-core vesicles in endocrine cells, and lysosomes in fibroblasts. It has been shown to play a role in regulation of Ca2+-dependent lysosomal exocytosis in fibroblasts and may also function as a vesicular Ca2+-sensor. It is distinguished from the other synaptotagmins by having over 12 splice forms. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the second C2 repeat, C2B, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204  95 LGDILFSVSYLPTAERLTVVVLKARNLKTMDINGSSDPFVKVSLLQGGRRVKKKKTSVRKCNCNPTWNEAIIFNVPAAAL 174
Cdd:cd08405     1 RGELLLSLCYNPTANRITVNIIKARNLKAMDINGTSDPYVKVWLMYKDKRVEKKKTVIKKRTLNPVFNESFIFNIPLERL 80

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 1752368204 175 NACSLELIVMDYDLLGQCEKIGETVVGPHSGGLGQDQWTEMVQTPRKPVSVWHTLR 230
Cdd:cd08405    81 RETTLIITVMDKDRLSRNDLIGKIYLGWKSGGLELKHWKDMLSKPRQPVAQWHRLK 136

C2 domain second repeat present in Synaptotagmin 12; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. Synaptotagmin 12, a member of class 6 synaptotagmins, is located in the brain. It functions are unknown. It, like synaptotagmins 8 and 13, do not have any consensus Ca2+ binding sites. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the second C2 repeat, C2B, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204  96 GDILFSVSYLPTAERLTVVVLKARNLKTMDINGSSDPFVKVSLLQGGRRVKKKKTSVRKCNCNPTWNEAIIFNVPAAALN 175
Cdd:cd08406     2 GEILLSLSYLPTAERLTVVVVKARNLVWDNGKTTADPFVKVYLLQDGRKISKKKTSVKRDDTNPIFNEAMIFSVPAIVLQ 81

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1752368204 176 ACSLELIVMDYDLLGQCEKIGETVVGPHSGGLGQDQWTEMVQTPRKPVSVWHTLR 230
Cdd:cd08406    82 DLSLRVTVAESTEDGKTPNVGHVIIGPAASGMGLSHWNQMLASLRKPVAMWHPLR 136

C2 domain second repeat present in Synaptotagmin 15; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. It is thought to be involved in the trafficking and exocytosis of secretory vesicles in non-neuronal tissues and is Ca2+ independent. Human synaptotagmin 15 has 2 alternatively spliced forms that encode proteins with different C-termini. The larger, SYT15a, contains a N-terminal TM region, a putative fatty-acylation site, and 2 tandem C terminal C2 domains. The smaller, SYT15b, lacks the C-terminal portion of the second C2 domain. Unlike most other synaptotagmins it is nearly absent in the brain and rather is found in the heart, lungs, skeletal muscle, and testis. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the second C2 repeat, C2B, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204  95 LGDILFSVSYLPTAERLTVVVLKARNLKTMDINgSSDPFVKVSLLQGGRRVKKKKTSVRKCNCNPTWNEAIIFNVPAAAL 174
Cdd:cd08409     1 LGDIQISLTYNPTLNRLTVVVLRARGLRQLDHA-HTSVYVKVSLMIHNKVVKTKKTEVVDGAASPSFNESFSFKVTSRQL 79

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1752368204 175 NACSLELIVMDYDLLGQCEKIGETVVGPHSGGLGQD--QWTEMVQTPRKPVSVWHTL 229
Cdd:cd08409    80 DTASLSLSVMQSGGVRKSKLLGRVVLGPFMYARGKEleHWNDMLSKPKELIKRWHAL 136

C2A domain first repeat present in Synaptotagmins 1, 5, 6, 9, and 10; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. Synaptotagmin 1, a member of class 1 synaptotagmins, is located in the brain and endocranium and localized to the synaptic vesicles and secretory granules. It functions as a Ca2+ sensor for fast exocytosis as do synaptotagmins 5, 6, and 10. It is distinguished from the other synaptotagmins by having an N-glycosylated N-terminus. Synaptotagmins 5, 6, and 10, members of class 3 synaptotagmins, are located primarily in the brain and localized to the active zone and plasma membrane. They is distinguished from the other synaptotagmins by having disulfide bonds at its N-terminus. Synaptotagmin 6 also regulates the acrosome reaction, a unique Ca2+-regulated exocytosis, in sperm. Synaptotagmin 9, a class 5 synaptotagmins, is located in the brain and localized to the synaptic vesicles. It is thought to be a Ca2+-sensor for dense-core vesicle exocytosis. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the first C2 repeat, C2A, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204   1 MDIGVSSDPYVKISLEPDEERKIKQSV-------VQNEIFKFPTTYEELQEKTVRFSVFDFDKFSRHDAIGEVLVRINDV 73
Cdd:cd08385    31 MDMGGTSDPYVKVYLLPDKKKKFETKVhrktlnpVFNETFTFKVPYSELGNKTLVFSVYDFDRFSKHDLIGEVRVPLLTV 110

                          90
                  ....*....|....
gi 1752368204  74 DVSRELDVWSELRS 87
Cdd:cd08385   111 DLGHVTEEWRDLES 124

C2 domain second repeat present in Rabphilin and Double C2 domain; Rabphilin is found neurons and in neuroendrocrine cells, while Doc2 is found not only in the brain but in tissues, including mast cells, chromaffin cells, and osteoblasts. Rabphilin and Doc2s share highly homologous tandem C2 domains, although their N-terminal structures are completely different: rabphilin contains an N-terminal Rab-binding domain (RBD),7 whereas Doc2 contains an N-terminal Munc13-1-interacting domain (MID). C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the second C2 repeat, C2B, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204  98 ILFSVSYLPTAERLTVVVLKARNLKTMDINGSSDPFVKVSLLQGGRRVKKKKTSVRKCNCNPTWNEAIIFNVPAAALNAC 177
Cdd:cd08384     2 ILVSLMYNTQRRGLIVGIIRCVNLAAMDANGYSDPFVKLYLKPDAGKKSKHKTQVKKKTLNPEFNEEFFYDIKHSDLAKK 81

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1752368204 178 SLELIVMDYDLLGQCEKIGETVVGPHSGGLGQDQWTEMVQTPRKPVSVWHTL 229
Cdd:cd08384    82 TLEITVWDKDIGKSNDYIGGLQLGINAKGERLRHWLDCLKNPDKKIEAWHTL 133

C2 domain second repeat in Munc13 (mammalian uncoordinated)-like proteins; C2-like domains are thought to be involved in phospholipid binding in a Ca2+ independent manner in both Unc13 and Munc13. Caenorabditis elegans Unc13 has a central domain with sequence similarity to PKC, which includes C1 and C2-related domains. Unc13 binds phorbol esters and DAG with high affinity in a phospholipid manner. Mutations in Unc13 results in abnormal neuronal connections and impairment in cholinergic neurotransmission in the nematode. Munc13 is the mammalian homolog which are expressed in the brain. There are 3 isoforms (Munc13-1, -2, -3) and are thought to play a role in neurotransmitter release and are hypothesized to be high-affinity receptors for phorbol esters. Unc13 and Munc13 contain both C1 and C2 domains. There are two C2 related domains present, one central and one at the carboxyl end. Munc13-1 contains a third C2-like domain. Munc13 interacts with syntaxin, synaptobrevin, and synaptotagmin suggesting a role for these as scaffolding proteins. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the third C2 repeat, C2C, and has a type-II topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204 103 SYLPTAERLTVVVLKARNLKTMDINGSSDPFVKVSLLQGGR--RVKKKKTSVRKCNCNPTWNEAIIFNVPAAAL---NAC 177
Cdd:cd04009    10 YYRASEQSLRVEILNARNLLPLDSNGSSDPFVKVELLPRHLfpDVPTPKTQVKKKTLFPLFDESFEFNVPPEQCsveGAL 89

                          90       100
                  ....*....|....*....|....*
gi 1752368204 178 sLELIVMDYDLLGQCEKIGETVVGP 202
Cdd:cd04009    90 -LLFTVKDYDLLGSNDFEGEAFLPL 113

C2A domain first repeat present in Synaptotagmins 15 and 17; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. It is thought to be involved in the trafficking and exocytosis of secretory vesicles in non-neuronal tissues and is Ca2+ independent. Human synaptotagmin 15 has 2 alternatively spliced forms that encode proteins with different C-termini. The larger, SYT15a, contains a N-terminal TM region, a putative fatty-acylation site, and 2 tandem C terminal C2 domains. The smaller, SYT15b, lacks the C-terminal portion of the second C2 domain. Unlike most other synaptotagmins it is nearly absent in the brain and rather is found in the heart, lungs, skeletal muscle, and testis. Synaptotagmin 17 is located in the brain, kidney, and prostate and is thought to be a peripheral membrane protein. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the first C2 repeat, C2A, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204   6 SSDPYVKISLEPDEeRKIKQSVVQ--------NEIFKFPTTYEELQEKTVRFSVFDFDKFSRHDAIGEVLVRINDVDVSR 77
Cdd:cd08390    35 HCDPFVKVCLLPDE-RRSLQSKVKrktqnpnfDETFVFQVSFKELQRRTLRLSVYDVDRFSRHCIIGHVLFPLKDLDLVK 113

                  ....*....
gi 1752368204  78 ELDVWSELR 86
Cdd:cd08390   114 GGVVWRDLE 122

Protein kinase C conserved region 2 (CalB); Ca2+-binding motif present in phospholipases, protein kinases C, and synaptotagmins (among others). Some do not appear to contain Ca2+-binding sites. Particular C2s appear to bind phospholipids, inositol polyphosphates, and intracellular proteins. Unusual occurrence in perforin. Synaptotagmin and PLC C2s are permuted in sequence with respect to N- and C-terminal beta strands. SMART detects C2 domains using one or both of two profiles.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204  110 RLTVVVLKARNLKTMDINGSSDPFVKVSLlqGGRRVKKKKTSVRKCNCNPTWNEAIIFNVPAAALNacSLELIVMDYDLL 189
Cdd:smart00239   1 TLTVKIISARNLPPKDKGGKSDPYVKVSL--DGDPKEKKKTKVVKNTLNPVWNETFEFEVPPPELA--ELEIEVYDKDRF 76

                           90
                   ....*....|.
gi 1752368204  190 GQCEKIGETVV 200
Cdd:smart00239  77 GRDDFIGQVTI 87

C2A domain first repeat present in Synaptotagmins 15 and 17; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. It is thought to be involved in the trafficking and exocytosis of secretory vesicles in non-neuronal tissues and is Ca2+ independent. Human synaptotagmin 15 has 2 alternatively spliced forms that encode proteins with different C-termini. The larger, SYT15a, contains a N-terminal TM region, a putative fatty-acylation site, and 2 tandem C terminal C2 domains. The smaller, SYT15b, lacks the C-terminal portion of the second C2 domain. Unlike most other synaptotagmins it is nearly absent in the brain and rather is found in the heart, lungs, skeletal muscle, and testis. Synaptotagmin 17 is located in the brain, kidney, and prostate and is thought to be a peripheral membrane protein. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the first C2 repeat, C2A, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204  96 GDILFSVSYLPTAERLTVVVLKARNLKTMDIN-GSSDPFVKVSLLQGGRRVKKkkTSVRKCNCNPTWNEAIIFNVPAAAL 174
Cdd:cd08390     1 GRLWFSVQYDLEEEQLTVSLIKARNLPPRTKDvAHCDPFVKVCLLPDERRSLQ--SKVKRKTQNPNFDETFVFQVSFKEL 78

                          90       100
                  ....*....|....*....|....*.
gi 1752368204 175 NACSLELIVMDYDLLGQCEKIGETVV 200
Cdd:cd08390    79 QRRTLRLSVYDVDRFSRHCIIGHVLF 104

C2A domain first repeat present in Synaptotagmins 1, 5, 6, 9, and 10; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. Synaptotagmin 1, a member of class 1 synaptotagmins, is located in the brain and endocranium and localized to the synaptic vesicles and secretory granules. It functions as a Ca2+ sensor for fast exocytosis as do synaptotagmins 5, 6, and 10. It is distinguished from the other synaptotagmins by having an N-glycosylated N-terminus. Synaptotagmins 5, 6, and 10, members of class 3 synaptotagmins, are located primarily in the brain and localized to the active zone and plasma membrane. They is distinguished from the other synaptotagmins by having disulfide bonds at its N-terminus. Synaptotagmin 6 also regulates the acrosome reaction, a unique Ca2+-regulated exocytosis, in sperm. Synaptotagmin 9, a class 5 synaptotagmins, is located in the brain and localized to the synaptic vesicles. It is thought to be a Ca2+-sensor for dense-core vesicle exocytosis. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the first C2 repeat, C2A, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204  95 LGDILFSVSYLPTAERLTVVVLKARNLKTMDINGSSDPFVKVSLLQGgrrvKKKK--TSVRKCNCNPTWNEAIIFNVPAA 172
Cdd:cd08385     2 LGKLQFSLDYDFQSNQLTVGIIQAADLPAMDMGGTSDPYVKVYLLPD----KKKKfeTKVHRKTLNPVFNETFTFKVPYS 77

                          90       100
                  ....*....|....*....|....*...
gi 1752368204 173 ALNACSLELIVMDYDLLGQCEKIGETVV 200
Cdd:cd08385    78 ELGNKTLVFSVYDFDRFSKHDLIGEVRV 105

C2A domain first repeat present in Synaptotagmin 7; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. Synaptotagmin 7, a member of class 2 synaptotagmins, is located in presynaptic plasma membranes in neurons, dense-core vesicles in endocrine cells, and lysosomes in fibroblasts. It has been shown to play a role in regulation of Ca2+-dependent lysosomal exocytosis in fibroblasts and may also function as a vesicular Ca2+-sensor. It is distinguished from the other synaptotagmins by having over 12 splice forms. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the first C2 repeat, C2A, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204   1 MDIGVSSDPYVKISLEPDEERKIKQSV-------VQNEIFKFPT-TYEELQEKTVRFSVFDFDKFSRHDAIGEVLVRIND 72
Cdd:cd08386    31 KDFSGTSDPFVKIYLLPDKKHKLETKVkrknlnpHWNETFLFEGfPYEKLQQRVLYLQVLDYDRFSRNDPIGEVSLPLNK 110

                          90
                  ....*....|....
gi 1752368204  73 VDVSRELDVWSELR 86
Cdd:cd08386   111 VDLTEEQTFWKDLK 124

C2 domain in Protein Kinase C (PKC) alpha and gamma; A single C2 domain is found in PKC alpha and gamma. The PKC family of serine/threonine kinases regulates apoptosis, proliferation, migration, motility, chemo-resistance, and differentiation. There are 3 groups: group 1(alpha, betaI, beta II, gamma) which require phospholipids and calcium, group 2 (delta, epsilon, theta, eta) which do not require calcium for activation, and group 3 (xi, iota/lambda) which are atypical and can be activated in the absence of diacylglycerol and calcium. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. Members here have a type-I topology.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1752368204  96 GDILFSVSYlpTAERLTVVVLKARNLKTMDINGSSDPFVKVSLLQGGRRVKKKKTSVRKCNCNPTWNEAIIFNV 169
Cdd:cd04026     2 GRIYLKISV--KDNKLTVEVREAKNLIPMDPNGLSDPYVKLKLIPDPKNETKQKTKTIKKTLNPVWNETFTFDL 73

C2 domain first repeat contained in Rab3-interacting molecule (RIM) proteins; RIMs are believed to organize specialized sites of the plasma membrane called active zones. They also play a role in controlling neurotransmitter release, plasticity processes, as well as memory and learning. RIM contains an N-terminal zinc finger domain, a PDZ domain, and two C-terminal C2 domains (C2A, C2B). C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. Members here have a type-I topology and do not bind Ca2+.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204  96 GDILFSVSYLPTAERLTVVVLKARNLKTMDINGSSDPFVKVSLLQGGRRVKKKKTSVRKCNCNPTWNEAIIF-NVPAAAL 174
Cdd:cd04031     3 GRIQIQLWYDKVTSQLIVTVLQARDLPPRDDGSLRNPYVKVYLLPDRSEKSKRRTKTVKKTLNPEWNQTFEYsNVRRETL 82

                          90       100
                  ....*....|....*....|....*.
gi 1752368204 175 NACSLELIVMDYDLLGQCEKIGETVV 200
Cdd:cd04031    83 KERTLEVTVWDYDRDGENDFLGEVVI 108

C2 domain first repeat present in Synaptotagmin-like proteins; All Slp members basically share an N-terminal Slp homology domain (SHD) and C-terminal tandem C2 domains (named the C2A domain and the C2B domain) with the SHD and C2 domains being separated by a linker sequence of various length. Slp1/JFC1 and Slp2/exophilin 4 promote granule docking to the plasma membrane. Additionally, their C2A domains are both Ca2+ independent, unlike the case in Slp3 and Slp4/granuphilin in which their C2A domains are Ca2+ dependent. It is thought that SHD (except for the Slp4-SHD) functions as a specific Rab27A/B-binding domain. In addition to Slps, rabphilin, Noc2, and Munc13-4 also function as Rab27-binding proteins. It has been demonstrated that Slp3 and Slp4/granuphilin promote dense-core vesicle exocytosis. Slp5 mRNA has been shown to be restricted to human placenta and liver suggesting a role in Rab27A-dependent membrane trafficking in specific tissues. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the first C2 repeat, C2A, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204  96 GDILFSVSYLPTAERLTVVVLKARNLKTMDI-NGSSDPFVKVSLLQGGRRVKKKKTSVRKCNCNPTWNEAIIFNVPAAAL 174
Cdd:cd08521     1 GEIEFSLSYNYKTGSLEVHIKECRNLAYADEkKKRSNPYVKVYLLPDKSKQSKRKTSVKKNTTNPVFNETLKYHISKSQL 80

                          90       100
                  ....*....|....*....|....*.
gi 1752368204 175 NACSLELIVMDYDLLGQCEKIGETVV 200
Cdd:cd08521    81 ETRTLQLSVWHHDRFGRNTFLGEVEI 106

C2A domain first repeat present in Synaptotagmin 8; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the first C2 repeat, C2A, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204   6 SSDPYVKISLEPDEERkIKQSVVQ--------NEIFKFPTTYEELQEKTVRFSVFDFDKFSRHDAIGEVLVRINDVDVSR 77
Cdd:cd08387    36 TADPYCKVRLLPDRSN-TKQSKIHkktlnpefDESFVFEVPPQELPKRTLEVLLYDFDQFSRDECIGVVELPLAEVDLSE 114

                          90
                  ....*....|
gi 1752368204  78 ELDVWSELRS 87
Cdd:cd08387   115 KLDLWRKIQS 124

C2 domain fifth repeat in Ferlin; Ferlins are involved in vesicle fusion events. Ferlins and other proteins, such as Synaptotagmins, are implicated in facilitating the fusion process when cell membranes fuse together. There are six known human Ferlins: Dysferlin (Fer1L1), Otoferlin (Fer1L2), Myoferlin (Fer1L3), Fer1L4, Fer1L5, and Fer1L6. Defects in these genes can lead to a wide range of diseases including muscular dystrophy (dysferlin), deafness (otoferlin), and infertility (fer-1, fertilization factor-1). Structurally they have 6 tandem C2 domains, designated as (C2A-C2F) and a single C-terminal transmembrane domain, though there is a new study that disputes this and claims that there are actually 7 tandem C2 domains with another C2 domain inserted between C2D and C2E. In a subset of them (Dysferlin, Myoferlin, and Fer1) there is an additional conserved domain called DysF. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the fifth C2 repeat, C2E, and has a type-II topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204 113 VVVLKARNLKTMDINGSSDPFVKVSLlqGGRRVKKKKTSVRKcNCNPTWNEAIIFN--VPAAALnacsLELIVMDYDLLG 190
Cdd:cd04037     4 VYVVRARNLQPKDPNGKSDPYLKIKL--GKKKINDRDNYIPN-TLNPVFGKMFELEatLPGNSI----LKISVMDYDLLG 76

                          90
                  ....*....|
gi 1752368204 191 QCEKIGETVV 200
Cdd:cd04037    77 SDDLIGETVI 86

C2 domain first repeat present in Synaptotagmin-like proteins 4 and 5; All Slp members basically share an N-terminal Slp homology domain (SHD) and C-terminal tandem C2 domains (named the C2A domain and the C2B domain) with the SHD and C2 domains being separated by a linker sequence of various length. SHD of Slp (except for the Slp4-SHD) function as a specific Rab27A/B-binding domain. In addition to Slp, rabphilin, Noc2, and Munc13-4 also function as Rab27-binding proteins. It has been demonstrated that Slp4/granuphilin promotes dense-core vesicle exocytosis. The C2A domain of Slp4 is Ca2+ dependent. Slp5 mRNA has been shown to be restricted to human placenta and liver suggesting a role in Rab27A-dependent membrane trafficking in specific tissues. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the first C2 repeat, C2A, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204  96 GDILFSVSYLPTAERLTVVVLKARNLKTMD-INGSSDPFVKVSLLQGGRRVKKKKTSVRKCNCNPTWNEAIIFNVPAAAL 174
Cdd:cd04029     2 GEILFSLSYDYKTQSLNVHVKECRNLAYGDeAKKRSNPYVKTYLLPDKSRQSKRKTSIKRNTTNPVYNETLKYSISHSQL 81

                          90       100
                  ....*....|....*....|....
gi 1752368204 175 NACSLELIVMDYDLLGQCEKIGET 198
Cdd:cd04029    82 ETRTLQLSVWHYDRFGRNTFLGEV 105

C2 domain second repeat present in RasA1 and RasA4; RasA1 and RasA4 are GAP1s (GTPase activating protein 1s ), Ras-specific GAP members, which suppresses Ras function by enhancing the GTPase activity of Ras proteins resulting in the inactive GDP-bound form of Ras. In this way it can control cellular proliferation and differentiation. Both proteins contain two C2 domains, a Ras-GAP domain, a plextrin homology (PH)-like domain, and a Bruton's Tyrosine Kinase (BTK) zinc binding domain. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the second C2 repeat, C2B, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204 110 RLTVVVLKARNLKTMDINGSSDPFVKVSLlqGGrrvKKKKTSVRKCNCNPTWNEAIIFNVPAAALNACSLEliVMDYDLL 189
Cdd:cd04025     1 RLRCHVLEARDLAPKDRNGTSDPFVRVFY--NG---QTLETSVVKKSCYPRWNEVFEFELMEGADSPLSVE--VWDWDLV 73

                          90
                  ....*....|...
gi 1752368204 190 GQCEKIGETVVGP 202
Cdd:cd04025    74 SKNDFLGKVVFSI 86

C2 domain second repeat present in class II phosphatidylinositol 3-kinases (PI3Ks); There are 3 classes of PI3Ks based on structure, regulation, and specificity. All classes contain a N-terminal C2 domain, a PIK domain, and a kinase catalytic domain. Unlike class I and class III, class II PI3Ks have additionally a PX domain and a C-terminal C2 domain containing a nuclear localization signal both of which bind phospholipids though in a slightly different fashion. PI3Ks (AKA phosphatidylinositol (PtdIns) 3-kinases) regulate cell processes such as cell growth, differentiation, proliferation, and motility. PI3Ks work on phosphorylation of phosphatidylinositol, phosphatidylinositide (4)P (PtdIns (4)P),2 or PtdIns(4,5)P2. Specifically they phosphorylate the D3 hydroxyl group of phosphoinositol lipids on the inositol ring. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the second C2 repeat, C2B, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204  96 GDILFSVSYlpTAERLTVVVLKARNLKTMDiNGSSDPFVKVSLLQGGRRVKKKKTSVRKCNCNPTWNEAIIFN-VPAAAL 174
Cdd:cd08381     2 GQVKLSISY--KNGTLFVMVMHAKNLPLLD-GSDPDPYVKTYLLPDPQKTTKRKTKVVRKTRNPTFNEMLVYDgLPVEDL 78

                          90       100
                  ....*....|....*....|....*.
gi 1752368204 175 NACSLELIVMDYDLLGQCEKIGETVV 200
Cdd:cd08381    79 QQRVLQVSVWSHDSLVENEFLGGVCI 104

C2 domain second repeat present in Synaptotagmin 7; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. Synaptotagmin 7, a member of class 2 synaptotagmins, is located in presynaptic plasma membranes in neurons, dense-core vesicles in endocrine cells, and lysosomes in fibroblasts. It has been shown to play a role in regulation of Ca2+-dependent lysosomal exocytosis in fibroblasts and may also function as a vesicular Ca2+-sensor. It is distinguished from the other synaptotagmins by having over 12 splice forms. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the second C2 repeat, C2B, and has a type-I topology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204   1 MDIGVSSDPYVKISLEPDEER--KIKQSV-------VQNEIFKFPTTYEELQEKTVRFSVFDFDKFSRHDAIGEVLVRIN 71
Cdd:cd08405    30 MDINGTSDPYVKVWLMYKDKRveKKKTVIkkrtlnpVFNESFIFNIPLERLRETTLIITVMDKDRLSRNDLIGKIYLGWK 109

C2 domain present in Arf GTPase Activating Proteins (GAP); ArfGAP is a GTPase activating protein which regulates the ADP ribosylation factor Arf, a member of the Ras superfamily of GTP-binding proteins. The GTP-bound form of Arf is involved in Golgi morphology and is involved in recruiting coat proteins. ArfGAP is responsible for the GDP-bound form of Arf which is necessary for uncoating the membrane and allowing the Golgi to fuse with an acceptor compartment. These proteins contain an N-terminal ArfGAP domain containing the characteristic zinc finger motif (Cys-x2-Cys-x(16,17)-x2-Cys) and C-terminal C2 domain. C2 domains were first identified in Protein Kinase C (PKC). C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752368204 111 LTVVVLKARNLKTMDINgSSDPFVKVSLLQggrrvKKKKTSVRKCNCNPTWNEAIIFNVPAAALnacSLELIVMDYDLLG 190
Cdd:cd04038     4 LKVRVVRGTNLAVRDFT-SSDPYVVLTLGN-----QKVKTRVIKKNLNPVWNEELTLSVPNPMA---PLKLEVFDKDTFS 74

                  ....*..
gi 1752368204 191 QCEKIGE 197
Cdd:cd04038    75 KDDSMGE 81