BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain superfamily; Proteins in this superfamily are characterized by the presence of a common protein-protein interaction motif of about 100 amino acids, known as the BTB/POZ domain. Members include transcription factors, oncogenic proteins, ion channel proteins, and potassium channel tetramerization domain (KCTD) proteins. They have been identified in poxviruses and many eukaryotes, and have diverse functions, such as transcriptional regulation, chromatin remodeling, protein degradation and cytoskeletal regulation. Many BTB/POZ proteins contain one or two additional domains, such as kelch repeats, zinc-finger domains, FYVE (Fab1, YOTB, Vac1, and EEA1) fingers, or ankyrin repeats, among others. These special additional domains or interaction partners provide unique characteristics and functions to BTB/POZ proteins. In ion channel proteins and KCTD proteins, the BTB/POZ domain is also called the tetramerization (T1) domain.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157   6 AAWLPFARAAAIGWMPVASGPMPAPPRQERKRtQDALIVLNVSGTRFQTWQDTLERYPDTLLGSSERDFFYHPETQQYFF 85
Cdd:cd18419     1 AAWLPFARAAAIGWMPVANCPMPLAPADKNKR-QDELIVLNVSGRRFQTWRTTLERYPDTLLGSTEKEFFFNEDTKEYFF 79

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1907171157  86 DRDPDIFRHILNFYRTGKLHYPRHECISAYDEELAFFGLIPEIIGDCCYEEYKDRRREN 144
Cdd:cd18419    80 DRDPEVFRCVLNFYRTGKLHYPRYECISAYDEELAFYGILPEIIGDCCYEEYKDRKREN 138

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily D member 3 (KCND3); KCND3, also called voltage-gated potassium channel subunit Kv4.3, is a pore-forming subunit of voltage-gated rapidly inactivating A-type potassium channels. Mutations in KCND3 cause spinocerebellar ataxia. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCND3 is an alpha subunit that forms functional homo- or hetero-tetrameric channels (with other Kv4/KCND alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif. It is modulated by cytoplasmic KChIPs/KCNIPs (Kv-channel interacting proteins), which are small calcium binding proteins with EF-hand-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157   6 AAWLPFARAAAIGWMPVASGPMPAPPRQERKRtQDALIVLNVSGTRFQTWQDTLERYPDTLLGSSERDFFYHPETQQYFF 85
Cdd:cd18419     1 AAWLPFARAAAIGWMPVANCPMPLAPADKNKR-QDELIVLNVSGRRFQTWRTTLERYPDTLLGSTEKEFFFNEDTKEYFF 79

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1907171157  86 DRDPDIFRHILNFYRTGKLHYPRHECISAYDEELAFFGLIPEIIGDCCYEEYKDRRREN 144
Cdd:cd18419    80 DRDPEVFRCVLNFYRTGKLHYPRYECISAYDEELAFYGILPEIIGDCCYEEYKDRKREN 138

Ion transport protein; This family contains sodium, potassium and calcium ion channels. This family is 6 transmembrane helices in which the last two helices flank a loop which determines ion selectivity. In some sub-families (e.g. Na channels) the domain is repeated four times, whereas in others (e.g. K channels) the protein forms as a tetramer in the membrane.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157 184 ALVFYYVTGFFIAVSVIANVVETVPCGSspghikelpcgERYAVAFFCLDTACVMIFTVEYLLRLAAAPSRYRFVRSVMS 263
Cdd:pfam00520   1 SRYFELFILLLILLNTIFLALETYFQPE-----------EPLTTVLEILDYVFTGIFTLEMLLKIIAAGFKKRYFRSPWN 69

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157 264 IIDVVAILPYYIGLVMTDNEDVSGaFVTLRVFRVFRIFKFSRHSQGLRILGYTLKSCASELGFLLFSLTMAIIIFATVMF 343
Cdd:pfam00520  70 ILDFVVVLPSLISLVLSSVGSLSG-LRVLRLLRLLRLLRLIRRLEGLRTLVNSLIRSLKSLGNLLLLLLLFLFIFAIIGY 148

                         170       180       190
                  ....*....|....*....|....*....|....*....
gi 1907171157 344 YAEKGS---------SASKFTSIPAAFWYTIVTMTTLGY 373
Cdd:pfam00520 149 QLFGGKlktwenpdnGRTNFDNFPNAFLWLFQTMTTEGW 187

voltage-gated potassium channel protein;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 1907171157 334 AIIIFATVMFYAEKGSS------ASKFTSIPAAFWYTIVTMTTLGY 373
Cdd:PRK10537  140 AVISITSLLFYSTFGALylgdgfSPPIESLSTAFYFSIVTMSTVGY 185

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily D member 3 (KCND3); KCND3, also called voltage-gated potassium channel subunit Kv4.3, is a pore-forming subunit of voltage-gated rapidly inactivating A-type potassium channels. Mutations in KCND3 cause spinocerebellar ataxia. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCND3 is an alpha subunit that forms functional homo- or hetero-tetrameric channels (with other Kv4/KCND alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif. It is modulated by cytoplasmic KChIPs/KCNIPs (Kv-channel interacting proteins), which are small calcium binding proteins with EF-hand-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157   6 AAWLPFARAAAIGWMPVASGPMPAPPRQERKRtQDALIVLNVSGTRFQTWQDTLERYPDTLLGSSERDFFYHPETQQYFF 85
Cdd:cd18419     1 AAWLPFARAAAIGWMPVANCPMPLAPADKNKR-QDELIVLNVSGRRFQTWRTTLERYPDTLLGSTEKEFFFNEDTKEYFF 79

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1907171157  86 DRDPDIFRHILNFYRTGKLHYPRHECISAYDEELAFFGLIPEIIGDCCYEEYKDRRREN 144
Cdd:cd18419    80 DRDPEVFRCVLNFYRTGKLHYPRYECISAYDEELAFYGILPEIIGDCCYEEYKDRKREN 138

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily D member 1 (KCND1); KCND1, also called voltage-gated potassium channel subunit Kv4.1, is a pore-forming subunit of voltage-gated rapidly inactivating A-type potassium channels. It may contribute to I (To) current in heart and I (Sa) current in neurons. Its properties are modulated by interactions with other alpha subunits and with regulatory subunits. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCND1 is an alpha subunit that forms functional homo- or hetero-tetrameric channels (with other Kv4/KCND alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif. It is modulated by cytoplasmic KChIPs/KCNIPs (Kv-channel interacting proteins), which are small calcium binding proteins with EF-hand-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157   6 AAWLPFARAAAIGWMPVASGPMPAPPRQERKRTqDALIVLNVSGTRFQTWQDTLERYPDTLLGSSERDFFYHPETQQYFF 85
Cdd:cd18417     1 ATWLPFARAAAVGWLPLAKKPMPKPPSDKKRRN-DEILVVNVSGRRFQTWKNTLDRYPDTLLGSSEKEFFYNEDTQEYFF 79

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1907171157  86 DRDPDIFRHILNFYRTGKLHYPRHECISAYDEELAFFGLIPEIIGDCCYEEYKDRRREN 144
Cdd:cd18417    80 DRDPEMFRHILNFYRTGRLHYPRHECIQAFDEELSFYGIIPEIIGDCCLEEYRDRKKEN 138

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in KCND/Kv4 subfamily of Shal-type voltage-dependent potassium channels; Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. The potassium voltage-gated channel subfamily Kv4, also known as subfamily D, contains three alpha subunit members, Kv4.1 (KCND1), Kv4.2 (KCND2), and Kv4.3 (KCND3), which are orthologs of the Shal gene in Drosophila. They are A-type potassium channels that mediate the native, fast inactivating (A-type) K+ current (IA) described both in the nervous system (A currents) and the heart (transient outward current). Kv4/KCND subfamily alpha subunits form functional homo- or hetero-tetrameric channels through their BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif. They are modulated by cytoplasmic KChIPs/KCNIPs (Kv-channel interacting proteins), which are small calcium binding proteins with EF-hand-like domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  42 LIVLNVSGTRFQTWQDTLERYPDTLLGSSERDFFYHPETQQYFFDRDPDIFRHILNFYRTGKLHYPRHECISAYDEELAF 121
Cdd:cd18380     1 RIVINVSGRRFETWKNTLEKYPDTLLGSTEKEFFYDDDTKEYFFDRDPEIFRHILNFYRTGKLHYPRHECISAYDDELAF 80

                          90       100
                  ....*....|....*....|..
gi 1907171157 122 FGLIPEIIGDCCYEEYKDRRRE 143
Cdd:cd18380    81 FGILPEIIGDCCYEDYRDRKRE 102

Ion transport protein; This family contains sodium, potassium and calcium ion channels. This family is 6 transmembrane helices in which the last two helices flank a loop which determines ion selectivity. In some sub-families (e.g. Na channels) the domain is repeated four times, whereas in others (e.g. K channels) the protein forms as a tetramer in the membrane.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157 184 ALVFYYVTGFFIAVSVIANVVETVPCGSspghikelpcgERYAVAFFCLDTACVMIFTVEYLLRLAAAPSRYRFVRSVMS 263
Cdd:pfam00520   1 SRYFELFILLLILLNTIFLALETYFQPE-----------EPLTTVLEILDYVFTGIFTLEMLLKIIAAGFKKRYFRSPWN 69

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157 264 IIDVVAILPYYIGLVMTDNEDVSGaFVTLRVFRVFRIFKFSRHSQGLRILGYTLKSCASELGFLLFSLTMAIIIFATVMF 343
Cdd:pfam00520  70 ILDFVVVLPSLISLVLSSVGSLSG-LRVLRLLRLLRLLRLIRRLEGLRTLVNSLIRSLKSLGNLLLLLLLFLFIFAIIGY 148

                         170       180       190
                  ....*....|....*....|....*....|....*....
gi 1907171157 344 YAEKGS---------SASKFTSIPAAFWYTIVTMTTLGY 373
Cdd:pfam00520 149 QLFGGKlktwenpdnGRTNFDNFPNAFLWLFQTMTTEGW 187

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in voltage-gated potassium (Kv) channels; Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. This family includes several groups of alpha subunits such as KCNA/Kv1 family of Shaker-type Kv channels, KCNB/Kv2 family of Shab-type Kv channels, KCNC/Kv3 family of Shaw-type Kv channels, KCND/Kv4 family of Shal-type Kv channels, KCNF/Kv5 subfamily of Kv channels, KCNG/Kv6 subfamily of Kv channels, KCNV/Kv8 subfamily of Kv channels, and KCNS/Kv9 subfamily of Kv channels. Kv alpha subunits form functional homo- or hetero-tetrameric channels (typically with other alpha subunits from the same subfamily) through their BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif. KCNQ/Kv7 channels are not included in this family, since they do not contain a BTB/POZ domain.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  43 IVLNVSGTRFQTWQDTLERYPDTLLGS-SERDFFYHPETQQYFFDRDPDIFRHILNFYRTGKLHYPRHECISAYDEELAF 121
Cdd:cd18317     1 VVLNVGGTRFELSRSTLLRFPDTRLGKlAKESHAYDESTNEYFFDRNPEVFEAILDYYRTGELHLPSNVCPASFKEELEF 80

                  ..
gi 1907171157 122 FG 123
Cdd:cd18317    81 WG 82

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily C members KCNC1 and KCNC3; KCNC1 (also called NGK2, voltage-gated potassium channel subunit Kv3.1, or voltage-gated potassium channel subunit Kv4) and KCNC3 (also called KSHIIID or voltage-gated potassium channel subunit Kv3.3) play important roles in the rapid repolarization of fast-firing brain neurons. Assuming opened or closed conformations in response to the voltage difference across the membrane, the proteins form tetrameric potassium-selective channels through which potassium ions may pass in accordance with their electrochemical gradient. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCNC1 and KCNC3 are alpha subunit that form functional homo- or hetero-tetrameric channels (with other alpha subunits) through their BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  43 IVLNVSGTRFQTWQDTLERYPDT-LLGSSERD----FFYHPETQQYFFDRDPDIFRHILNFYRTGKLHYPRHECISAYDE 117
Cdd:cd18414     5 IVINVGGTRHETYRSTLRTLPGTrLAWLAEPDahsnFDYDPRADEFFFDRHPGVFAHILNYYRTGKLHCPADVCGPLYEE 84

                          90       100       110
                  ....*....|....*....|....*....|...
gi 1907171157 118 ELAFFGLIPEIIGDCCYEEYKDRRreNAERLQD 150
Cdd:cd18414    85 ELAFWGIDETDVEPCCWMTYRQHR--DAEEALD 115

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in KCNB/Kv2 subfamily of Shab-type voltage-dependent potassium channels; Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. The potassium voltage-gated channel subfamily Kv3, also known as subfamily C, contains two alpha subunit members, Kv2.1 (KCNB1) and Kv2.2 (KCNB2), which are orthologs of the Shab gene in Drosophila. They are delayed-rectifier potassium currents in various neurons, although their physiological roles often remain elusive. Kv2/KCNB subfamily alpha subunits form functional homo- or hetero-tetrameric channels (with other alpha subunits) through their BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  45 LNVSGTRFQTWQDTLERYPDTLLG-----SSERDFF-----YHPETQQYFFDRDPDIFRHILNFYRTGKLHYPRHECISA 114
Cdd:cd18378     6 LNVGGVRHEVLWRTLDRLPRTRLGrlrecNTHESLLelcddYDLEDNEYFFDRHPGAFTSILNFYRTGKLHMPEEMCVLS 85

                          90       100
                  ....*....|....*....|...
gi 1907171157 115 YDEELAFFGLIPEIIGDCCYEEY 137
Cdd:cd18378    86 FSQELEYWGIDEIYLESCCQHRY 108

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily V member 1 (KCNV1); KCNV1, also called neuronal potassium channel alpha subunit HNKA or voltage-gated potassium channel subunit Kv8.1, is a new neuronal voltage-gated potassium channel alpha subunit with specific inhibitory properties towards Shab and Shaw channels. It modulates KCNB1 (also known as Kv2.1) and KCNB2 (also known as Kv2.2) channel activity by shifting the threshold for inactivation to more negative values and by slowing the rate of inactivation. It can also down-regulate the channel activity of KCNB1, KCNB2, KCNC4 (also known as Kv3.4) and KCND1 (also known as Kv4.1), possibly by trapping them in intracellular membranes. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCNV1 is a regulatory alpha subunit that cannot form a functional homo-tetrameric channel. It forms hetero-tetrameric channels (with other functional alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  43 IVLNVSGTRFQTWQDTLERYPDTLLG---SSERDFFY------HPETQQYFFDRDPDIFRHILNFYRTGKLHYPRHECIS 113
Cdd:cd18424     1 FTINVGGSRFVLSQQVLSSHPETRLGklaVSVRDSVLelcddaNFVDNEYFFDRSSQAFKYIMNYYKTGHLHVMEELCAI 80

                          90       100       110
                  ....*....|....*....|....*....|
gi 1907171157 114 AYDEELAFFGLIPEIIGDCCYEEYKdRRRE 143
Cdd:cd18424    81 SFLQEIEYWGIDELSIDSCCRERYY-RRKE 109

Broad-Complex, Tramtrack and Bric a brac; Domain in Broad-Complex, Tramtrack and Bric a brac. Also known as POZ (poxvirus and zinc finger) domain. Known to be a protein-protein interaction motif found at the N-termini of several C2H2-type transcription factors as well as Shaw-type potassium channels. Known structure reveals a tightly intertwined dimer formed via interactions between N-terminal strand and helix structures. However in a subset of BTB/POZ domains, these two secondary structures appear to be missing. Be aware SMART predicts BTB/POZ domains without the beta1- and alpha1-secondary structures.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157   43 IVLNVSGTRFQTWQDTLERYPDTLLGSSERDFFYHPETQQYFFDRDPDIFRHILNFYRTGKLHYPRhECISAYDEELAFF 122
Cdd:smart00225   2 VTLVVGGKKFHAHKAVLAAHSPYFKALFSSDFKESDKSEIYLDDVSPEDFRALLNFLYTGKLDLPE-ENVEELLELADYL 80

                           90
                   ....*....|....*...
gi 1907171157  123 gLIPEIIGDCCYEEYKDR 140
Cdd:smart00225  81 -QIPGLVELCEEFLLKLL 97

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily S member 3 (KCNS3); KCNS3, also called delayed-rectifier K(+) channel alpha subunit 3 or voltage-gated potassium channel subunit Kv9.3, is an alpha subunit of voltage-gated potassium channel linked to tissue oxygenation responses. It can form functional heterotetrameric channels with KCNB1 (also known as Kv2.1), and further modulates the delayed rectifier voltage-gated potassium channel activation and deactivation rates of KCNB1. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCNS3 is a regulatory alpha subunit that cannot form a functional homo-tetrameric channel. It forms hetero-tetrameric channels (with other functional alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  42 LIVLNVSGTRFQTWQDTLERYPDTLLG-----SSERDFF-----YHPETQQYFFDRDPDIFRHILNFYRTGKLHYPRHEC 111
Cdd:cd18428     2 LINLNVGGFKQSVDQSTLLRFPHTRLGkllncHSEEAILelcddYSVADKEYYFDRNPSLFRYVLNFYYTGKLHVMEELC 81

                          90       100
                  ....*....|....*....|....*..
gi 1907171157 112 ISAYDEELAFFGLIPEIIGDCCYEEYK 138
Cdd:cd18428    82 VFSFCQEIEYWGINELFIDSCCSNRYQ 108

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Drosophila melanogaster potassium voltage-gated channel protein Shab and similar proteins; Shab is a slow delayed rectifier voltage-gated potassium channel in Drosophila. It mediates transmembrane potassium transport in excitable membranes. Assuming opened or closed conformations in response to the voltage difference across the membrane, the protein forms a tetrameric potassium-selective channel through which potassium ions may pass in accordance with their electrochemical gradient. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. Shab is an alpha subunit that forms functional homo- or hetero-tetrameric channels (with other alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  43 IVLNVSGTRFQTWQDTLERYPDTLLGSSeRDFFYHPET-----------QQYFFDRDPDIFRHILNFYRTGKLHYPRHEC 111
Cdd:cd18413     4 VVINVGGVKHEVLWRTLDRMPHTRLGKL-RDSNTHEAIvelcddysladNEYFFDRHPRSFASILNFYRTGKLHLVEEMC 82

                          90       100
                  ....*....|....*....|....*.
gi 1907171157 112 ISAYDEELAFFGLIPEIIGDCCYEEY 137
Cdd:cd18413    83 VLAFSDDLEYWGVDELYLESCCQHKY 108

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Drosophila melanogaster potassium voltage-gated channel protein Shaker and similar proteins; Shaker, also termed protein minisleep, represents a family of putative potassium channel proteins in the nervous system of Drosophila. It is a voltage-gated potassium channel that mediates transmembrane potassium transport in excitable membranes. Assuming opened or closed conformations in response to the voltage difference across the membrane, the protein forms a tetrameric potassium-selective channel through which potassium ions may pass in accordance with their electrochemical gradient. Shaker plays a role in the regulation of sleep need or efficiency. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. Shaker is an alpha subunit that forms functional homo- or hetero-tetrameric channels (with other alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  43 IVLNVSGTRFQTWQDTLERYPDTLLGSSERDF-FYHPETQQYFFDRDPDIFRHILNFYRT-GKLHYPRHECISAYDEELA 120
Cdd:cd18410     3 VVINVSGLRFETQLKTLNQFPDTLLGDPQRRNrYYDPLRNEYFFDRNRPSFDAILYYYQSgGRLRRPVNVPLDVFSEEIK 82

                          90
                  ....*....|....*....
gi 1907171157 121 FFGLipeiiGDCCYEEYKD 139
Cdd:cd18410    83 FYEL-----GENAFEKYRE 96

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 3 (KCTD3) and SH3KBP1-binding protein 1 (SHKBP1); The group of KCTD proteins includes KCTD3 and SHKBP1. KCTD3, also called renal carcinoma antigen NY-REN-45, is a BTB/POZ domain-containing protein that is an accessory subunit of potassium/sodium hyperpolarization-activated cyclic nucleotide-gated channel 3 (HCN3), upregulating its cell-surface expression and current density without affecting its voltage dependence and kinetics. SHKBP1, also called SETA-binding protein 1, interacts with cathepsin B and participates in tumor necrosis factor (TNF)-induced apoptosis in ovarian cancer cells. It can promote epidermal growth factor receptor (EGFR) signaling by interrupting c-Cbl-CIN85 complex and inhibiting EGFR degradation. The BTB/POZ domain, also known as tetramerization (T1) domain, is a versatile protein-protein interaction motif that facilitates homodimerization or heterodimerization. KCTD family BTB domains can adopt a wide range of oligomerization geometries, including homodimerization, tetramerization, and pentamerization.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  40 DALIVLNVSGTRFQTWQDTLERYPDTLLGS--SERDFFYHPETQQYFFDRDPDIFRHILNFYRTGKLHyPRHECISAYDE 117
Cdd:cd18363     1 GDIINLNVGGKRFSTSRQTLTWIPDSFFTSllSGRISSLKDETGAIFIDRDPKLFSIILNYLRTKEID-LRNVDISSLRH 79

                  ....*..
gi 1907171157 118 ELAFFGL 124
Cdd:cd18363    80 EAEFYGI 86

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in KCNF/Kv5 subfamily of potassium voltage-gated channels; Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. The potassium voltage-gated channel subfamily Kv5, also known as subfamily F, only contains KCNF1 (also known as Kv5.1 or kH1), which functions as a regulatory alpha-subunit of voltage-gated potassium channel that when coassembled with Kv2.1 can modulate gating in a physiologically relevant manner. It forms hetero-tetrameric channels (with other alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  43 IVLNVSGTRFQTWQDTLERYPDTLL-------GSSERDFF-----YHPETQQYFFDRDPDIFRHILNFYRTGKLHYPRHE 110
Cdd:cd18381     3 IVVNVGGVRQVLYGDVLNRYPETRLaellnclSGGYDAIFslcddYDPGKREFYFDRDPDAFKCIIEVYYYGEIHMKKGI 82

                          90       100       110
                  ....*....|....*....|....*....|...
gi 1907171157 111 CISAYDEELAFFGLIPEIIGDCCYEEYKDRRRE 143
Cdd:cd18381    83 CPICFKNEMDFWRVDLDFLDECCKCHLSEKREE 115

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily S member 1 (KCNS1); KCNS1, also called delayed-rectifier K(+) channel alpha subunit 1 or voltage-gated potassium channel subunit Kv9.1, is a modulatory alpha subunit of voltage-gated potassium channel that mediates neuropathic pain following nerve injury. It can form functional heterotetrameric channels with KCNB1 (also known as Kv2.1) and KCNB2 (also known as Kv2.2), and further modulates the delayed rectifier voltage-gated potassium channel activation and deactivation rates of KCNB1 and KCNB2. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCNS1 is a regulatory alpha subunit that cannot form a functional homo-tetrameric channel. It forms hetero-tetrameric channels (with other functional alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  43 IVLNVSGTRFQTWQDTLERYPDTLLG-----SSERDFF-----YHPETQQYFFDRDPDIFRHILNFYRTGKLHYPRHECI 112
Cdd:cd18426     1 ININVGGLKRRLSSSTLSKFPDTRLGrllscDSEESILqicddYDVSAKEFYFDRNPGLFPYVLHFYQTGKLHIMEELCV 80

                          90       100
                  ....*....|....*....|....*
gi 1907171157 113 SAYDEELAFFGLIPEIIGDCCYEEY 137
Cdd:cd18426    81 FSFSQEIEYWGINEFFLDSCCSYRY 105

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily V member 2 (KCNV2); KCNV2, also called voltage-gated potassium channel subunit Kv8.2, is a modulatory voltage-gated potassium channel alpha subunit that modulates channel activity by shifting the threshold and the half-maximal activation to more negative values. KCNV2 is essential for visual function and cone survival. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCNV2 is a regulatory alpha subunit that cannot form a functional homo-tetrameric channel. It forms hetero-tetrameric channels (with other functional alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  45 LNVSGTRFQTWQDTLERYPDTLLG--------SSERDFF--YHPETQQYFFDRDPDIFRHILNFYRTGKLHYPRHECISA 114
Cdd:cd18425     3 INVGGTSYQISYRVAASYPKTRIGrlatytdrSRKLDLCddYNVQNDEYFFDRDPAVFHHIYNFYRTGVLWVKDELCPRN 82

                          90       100
                  ....*....|....*....|....*.
gi 1907171157 115 YDEELAFFGLIPEIIGDCCYEEYKDR 140
Cdd:cd18425    83 FLEEINYWGVRIKNTPRCCRISFEER 108

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily S member 2 (KCNS2); KCNS2, also called delayed-rectifier K(+) channel alpha subunit 2 or voltage-gated potassium channel subunit Kv9.2, is a modulatory alpha subunit of voltage-gated potassium channel that can form functional heterotetrameric channels with KCNB1 (also known as Kv2.1) and KCNB2 (also known as Kv2.2), and further modulates the delayed rectifier voltage-gated potassium channel activation and deactivation rates of KCNB1 and KCNB2. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCNS2 is a regulatory alpha subunit that cannot form a functional homo-tetrameric channel. It forms hetero-tetrameric channels (with other functional alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  43 IVLNVSGTRFQTWQDTLERYPDTLLGS-----SERDFF-----YHPETQQYFFDRDPDIFRHILNFYRTGKLHYPRHECI 112
Cdd:cd18427     2 ISINVGGFKKRLRSHTLLRFPETRLGRllscrSKESILelcddYDDTKNEFYFDRNPELFPYVLHFYNTGKLHVMGELCV 81

                          90       100
                  ....*....|....*....|....*
gi 1907171157 113 SAYDEELAFFGLIPEIIGDCCYEEY 137
Cdd:cd18427    82 FSFSQEIEYWGINEFFIDSCCSYSY 106

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily B member 1 (KCNB1); KCNB1, also called delayed rectifier potassium channel 1 (DRK1) or voltage-gated potassium channel subunit Kv2.1, mediates transmembrane potassium transport in excitable membranes, primarily in the brain, but also in the pancreas and cardiovascular system. Assuming opened or closed conformations in response to the voltage difference across the membrane, the protein forms a tetrameric potassium-selective channel through which potassium ions may pass in accordance with their electrochemical gradient. KCNB1 is involved in the regulation of the action potential (AP) repolarization, duration and frequency of repetitive AP firing in neurons, muscle cells and endocrine cells and plays a role in homeostatic attenuation of electrical excitability throughout the brain. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCNB1 is an alpha subunit that forms functional homo- or hetero-tetrameric channels (with other alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  43 IVLNVSGTRFQTWQDTLERYPDTLLGSSeRDFFYHP-----------ETQQYFFDRDPDIFRHILNFYRTGKLHYPRHEC 111
Cdd:cd18411    12 VKLNVGGLAHEVLWRTLDRLPRTRLGKL-RDCNTHEslmeicddynlEENEYFFDRHPGAFTSILNFYRTGKLHMMEEMC 90

                          90       100
                  ....*....|....*....|....*.
gi 1907171157 112 ISAYDEELAFFGLIPEIIGDCCYEEY 137
Cdd:cd18411    91 ALSFSQELDYWGIDEIYLESCCQARY 116

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily A member 5 (KCNA5); KCNA5, also called HPCN1, voltage-gated potassium channel HK2, or voltage-gated potassium channel subunit Kv1.5, mediates transmembrane potassium transport in excitable membranes. Assuming opened or closed conformations in response to the voltage difference across the membrane, the protein forms a tetrameric potassium-selective channel through which potassium ions may pass in accordance with their electrochemical gradient. KCNA5 may play a role in regulating the secretion of insulin in normal pancreatic islets. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCNA5 is an alpha subunit that forms functional homo- or hetero-tetrameric channels (with other Kv1/KCNA alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  43 IVLNVSGTRFQTWQDTLERYPDTLLGSSERDF-FYHPETQQYFFDRDPDIFRHILNFYRT-GKLHYPRHECISAYDEELA 120
Cdd:cd18406     3 VIINIAGLRFETQLGTLNQFPDTLLGDPDKRMrYFDPLRNEYFFDRNRPSFDGILYFYQSgGKIRRPVNVSIDVFADEIR 82

                  ....
gi 1907171157 121 FFGL 124
Cdd:cd18406    83 FYQL 86

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein KCTD11; KCTD11 may function as an antagonist of the Hedgehog pathway of cell proliferation and differentiation by affecting the nuclear transfer of transcription factor GLI1, thus maintaining cerebellar granule cells in the undifferentiated state. It is a probable substrate-specific adapter for a BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex towards HDAC1. It contains a BTB/POZ domain; in some cases the domain may be truncated. The BTB/POZ domain, also known as tetramerization (T1) domain, is a versatile protein-protein interaction motif that facilitates homodimerization or heterodimerization. KCTD family BTB domains can adopt a wide range of oligomerization geometries, including homodimerization, tetramerization, and pentamerization. Variants of the human/mouse KCTD11 appear to contain truncated BTB/POZ domains.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1907171157  43 IVLNVSGTRFQTWQDTLERYPDTLLGSSER-----DFFYHPETQ-QYFFDRDPDIFRHILNFYRTGKLHYPR 108
Cdd:cd18370     1 VTLNVGGTLYSTTLETLTRFPDSMLGAMFRagtpiPPNLNMQGGgHYFIDRDGKAFRHILNFLRLGRLDLPR 72

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily A member 1 (KCNA1); KCNA1 is also called voltage-gated K(+) channel HuKI, voltage-gated potassium channel HBK1, or voltage-gated potassium channel subunit Kv1.1. It mediates transmembrane potassium transport in excitable membranes, primarily in the brain and the central nervous system, but also in the kidney. It is involved in the regulation of the membrane potential and nerve signaling, and prevents neuronal hyperexcitability. Assuming opened or closed conformations in response to the voltage difference across the membrane, the protein forms a tetrameric potassium-selective channel through which potassium ions may pass in accordance with their electrochemical gradient. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCNA1 is an alpha subunit that forms functional homo- or hetero-tetrameric channels (with other Kv1/KCNA alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  43 IVLNVSGTRFQTWQDTLERYPDTLLGSSERDF-FYHPETQQYFFDRDPDIFRHILNFYRT-GKLHYPRHECISAYDEELA 120
Cdd:cd18402    11 VVINIAGLRFETQLKTLAQFPNTLLGNPKKRMrYFDPLRNEYFFDRNRPSFDAILYYYQSgGRLRRPVNVPLDMFSEEIK 90

                  ....*..
gi 1907171157 121 FFGLIPE 127
Cdd:cd18402    91 FYELGEE 97

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in SH3KBP1-binding protein 1 (SHKBP1); SHKBP1, also called SETA-binding protein 1, interacts with cathepsin B and participates in tumor necrosis factor (TNF)-induced apoptosis in ovarian cancer cells. It can promote epidermal growth factor receptor (EGFR) signaling by interrupting c-Cbl-CIN85 complex and inhibiting EGFR degradation. It contains a BTB/POZ domain, also known as tetramerization (T1) domain, a versatile protein-protein interaction motif that facilitates homodimerization or heterodimerization. KCTD family BTB domains can adopt a wide range of oligomerization geometries, including homodimerization, tetramerization, and pentamerization.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  42 LIVLNVSGTRFQTWQDTLERYPDTLLGS--SERDFFYHPETQQYFFDRDPDIFRHILNFYRTGKLHyPRHECISAYDEEL 119
Cdd:cd18393     3 VIHLNVGGKRFSTSRQTLTWIPDSFFSSllSGRISTLKDETGAIFIDRDPTVFAPILNFLRTKELD-PRGIHVSLLLHEA 81

                  ....*..
gi 1907171157 120 AFFGLIP 126
Cdd:cd18393    82 QFYGITP 88

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 4 (KCTD4); KCTD4 is a BTB/POZ domain-containing protein with an unknown biological function. KCTD proteins play crucial roles in a variety of fundamental biological processes, such as protein ubiquitination and degradation, suppression of proliferation or transcription, cytoskeleton regulation, tetramerization and gating of ion channels and others. Some KCTD proteins are involved in protein ubiquitination as part of the CRL (Cullin RING Ligase) E3 ligases. The BTB/POZ domain, also known as tetramerization (T1) domain, is a versatile protein-protein interaction motif that facilitates homodimerization or heterodimerization. KCTD family BTB domains can adopt a wide range of oligomerization geometries, including homodimerization, tetramerization, and pentamerization.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1907171157  42 LIVLNVSGTRFQTWQDTLERYPDTLLGS--SERDFFYHPETQQYFFDRDPDIFRHILNFYRTGKLHYP 107
Cdd:cd18364     1 LVTLNVGGYLYITQRQTLTKYPDSFLEGmvNGKIQCTVDADGNYFIDRDGLLFRHVLNFLRNGELLLP 68

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 3 (KCTD3); KCTD3, also called renal carcinoma antigen NY-REN-45, is a BTB/POZ domain-containing protein that is an accessory subunit of potassium/sodium hyperpolarization-activated cyclic nucleotide-gated channel 3 (HCN3), upregulating its cell-surface expression and current density without affecting its voltage dependence and kinetics. The BTB/POZ domain, also known as tetramerization (T1) domain, is a versatile protein-protein interaction motif that facilitates homodimerization or heterodimerization. KCTD family BTB domains can adopt a wide range of oligomerization geometries, including homodimerization, tetramerization, and pentamerization.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  42 LIVLNVSGTRFQTWQDTLERYPDTLLGS--SERDFFYHPETQQYFFDRDPDIFRHILNFYRTGKLHyPRHECISAYDEEL 119
Cdd:cd18392     3 IIQLNVGGTRFSTSRQTLMWIPDSFFSSllSGRISSLKDETGAIFIDRDPTAFVPILNFLRTKELD-LRGVNINVLRHEA 81

                  ....*..
gi 1907171157 120 AFFGLIP 126
Cdd:cd18392    82 EFYGITP 88

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily G members, KCNG1 and KCNG2; KCNG1, also called voltage-gated potassium channel subunit Kv6.1 or kH2, functions as a regulatory alpha-subunit of voltage-gated potassium channel that can form functional heterotetrameric channels with KCNB1 (also known as Kv2.1), and further modulates the delayed rectifier voltage-gated potassium channel activation and deactivation rates of KCNB1. KCNG2, also called cardiac potassium channel subunit or voltage-gated potassium channel subunit Kv6.2, is a new gamma-subunit of voltage-gated potassium channels that can form functional heterodimeric channels with KCNB1, and further modulates channel activity by shifting the threshold and the half-maximal activation to more negative values. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCNG1 and KCNG2 are regulatory alpha subunits and do not form homomultimers. They form heteromultimers (with other alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  34 ERKRTqdalIVLNVSGTRFQTWQDTLERYPDTLLG-----SSERDFF-----YHPETQQYFFDRDPDIFRHILNFYRTGK 103
Cdd:cd18421     1 DRTRH----VIINVGGIKYRIPWTTLEEFPLTRLGqlkscNNFDEIMdicddYDVTCNEFFFDRNPCAFRTILTFLRAGK 76

                          90       100       110
                  ....*....|....*....|....*....|....*..
gi 1907171157 104 LHYPRHECISAYDEELAFFGLIPEIIGDCCYEEYKDR 140
Cdd:cd18421    77 LRLLREMCALSFQEELLYWGIEEENLEWCCRRRLLQK 113

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing proteins, KCTD1 and KCTD15; This subfamily of KCTD proteins includes KCTD1 and KCTD15. KCTD1 is a nuclear BTB/POZ domain-containing protein that acts as a transcriptional repressor and mediates protein-protein interactions through a BTB domain. It represses the transcriptional activity of AP-2 family members, including TFAP2A, TFAP2B and TFAP2C. It also functions as a novel inhibitor of the Wnt signaling pathway. Mutations in KCTD1 cause scalp-ear-nipple (SEN) syndrome. KCTD15 is a BTB/POZ domain-containing protein that plays a role in the regulation of neural crest (NC) formation and other steps in embryonic development. It inhibits AP2 transcriptional activity by interaction with its activation domain. The BTB/POZ domain, also known as tetramerization (T1) domain, is a versatile protein-protein interaction motif that facilitates homodimerization or heterodimerization. KCTD family BTB domains can adopt a wide range of oligomerization geometries, including homodimerization, tetramerization, and pentamerization. The KCTD1 BTB domains form pentamers.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  45 LNVSGTRFQTWQDTLERYPDTLLGSserdFFYHPE-------TQQYFFDRDPDIFRHILNFYRTGKLHYPrhECISAYD- 116
Cdd:cd18361     3 IDVGGHIYTSSLETLTKYPESRLGK----LFNGSIpivldslKQHYFIDRDGKMFRHILNFLRTSKLLLP--DDFTEFDl 76

                          90
                  ....*....|....
gi 1907171157 117 --EELAFFGLIPEI 128
Cdd:cd18361    77 lyEEARYYELQPMV 90

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing proteins KCTD2, KCTD5, and KCTD17, and similar proteins; This subfamily includes potassium channel tetramerization domain-containing proteins KCTD2, KCTD5, and KCTD17, all of which function as adaptors of Cullin3 based ubiquitin E3 ubiquitin ligases. KCTD2 suppresses gliomagenesis by destabilizing c-Myc. KCTD5 is a negative regulator of the AKT pathway, a key signaling cascade frequently deregulated in cancer. KCTD5 does not impact the operation of Kv4.2, Kv3.4, Kv2.1, or Kv1.2 channels. KCTD17 polyubiquitylates trichoplein, a protein involved in ciliogenesis down-regulation. It is a positive regulator of ciliogenesis, playing a crucial role in the initial steps of axoneme extension. A missense mutation in KCTD17 causes autosomal dominant myoclonus-dystonia (M-D). The BTB/POZ domain, also known as tetramerization (T1) domain, is a versatile protein-protein interaction motif that facilitates homodimerization or heterodimerization. KCTD family BTB domains can adopt a wide range of oligomerization geometries, including homodimerization, tetramerization, and pentamerization. KCTD5 and KCTD17 BTB domains form pentamer structures.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907171157  43 IVLNVSGTRFQTWQDTLERYPDTLLG---------SSERDffyhpETQQYFFDRDPDIFRHILNFYRTGKLHYPRHECIS 113
Cdd:cd18362     2 VKLNVGGTYFLTTRTTLCRDPKSFLCrlcqedpdlPSDKD-----ETGAYLIDRDPTYFGPILNYLRHGKLIIDKDLAEE 76