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 767904241  186 YYVTGFFIAVSVITNVVeTVPCGTVPGSKElpcgeRYSVAFFCLDTACVMIFTVEYLLRLFAAPSRYRFIRSVMSIIDVV 265
Cdd:pfam00520   1 SRYFELFILLLILLNTI-FLALETYFQPEE-----PLTTVLEILDYVFTGIFTLEMLLKIIAAGFKKRYFRSPWNILDFV 74

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767904241  266 AIMPYYIGLVMTNNEDVSGaFVTLRVFRVFRIFKFSRHSQGLRILGYTLKSCASELGFLLFSLTMAIIIFATVMFYAEKG 345
Cdd:pfam00520  75 VVLPSLISLVLSSVGSLSG-LRVLRLLRLLRLLRLIRRLEGLRTLVNSLIRSLKSLGNLLLLLLLFLFIFAIIGYQLFGG 153

                         170       180       190
                  ....*....|....*....|....*....|...
gi 767904241  346 S---------SASKFTSIPASFWYTIVTMTTLG 369
Cdd:pfam00520 154 KlktwenpdnGRTNFDNFPNAFLWLFQTMTTEG 186

BTB/POZ domain; In voltage-gated K+ channels this domain is responsible for subfamily-specific assembly of alpha-subunits into functional tetrameric channels. In KCTD1 this domain functions as a transcriptional repressor. It also mediates homomultimerization of KCTD1 and interaction of KCTD1 with the transcription factor AP-2-alpha.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767904241   42 IVLNVSGRRFQTWRTTLERYPDTLLGSTEKE--FFFNEDTKEYFFDRDPEVFRCVLNFYRT-GKLHYPRYECISAYDDEL 118
Cdd:pfam02214   1 VKLNVGGTRFETLKSTLTRFPDTRLGRLLELecDDYDDDTNEYFFDRSPKHFETILNFYRTgGKLHRPEEVCLDEFLEEA 80

                          90
                  ....*....|...
gi 767904241  119 AFYGILPEIIGDC 131
Cdd:pfam02214  81 EFYGLDELALELC 93

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 767904241    42 IVLNVSGRRFQTWRTTLERYPDTLLGSTEKEFFFNEDTKEYFFDRDPEVFRCVLNFYRTGKLHYPRyECISAYDDELAFY 121
Cdd:smart00225   2 VTLVVGGKKFHAHKAVLAAHSPYFKALFSSDFKESDKSEIYLDDVSPEDFRALLNFLYTGKLDLPE-ENVEELLELADYL 80

                           90
                   ....*....|....*...
gi 767904241   122 GIlPEIIGDCCYEEYKDR 139
Cdd:smart00225  81 QI-PGLVELCEEFLLKLL 97

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 767904241   6 AAWLPFARAAAIGWMPVANCPMPLAPADKNKRQDELIVLNVSGRRFQTWRTTLERYPDTLLGSTEKEFFFNEDTKEYFFD 85
Cdd:cd18417    1 ATWLPFARAAAVGWLPLAKKPMPKPPSDKKRRNDEILVVNVSGRRFQTWKNTLDRYPDTLLGSSEKEFFYNEDTQEYFFD 80

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|....*...
gi 767904241  86 RDPEVFRCVLNFYRTGKLHYPRYECISAYDDELAFYGILPEIIGDCCYEEYKDRKREN 143
Cdd:cd18417   81 RDPEMFRHILNFYRTGRLHYPRHECIQAFDEELSFYGIIPEIIGDCCLEEYRDRKKEN 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 767904241  41 LIVLNVSGRRFQTWRTTLERYPDTLLGSTEKEFFFNEDTKEYFFDRDPEVFRCVLNFYRTGKLHYPRYECISAYDDELAF 120
Cdd:cd18380    1 RIVINVSGRRFETWKNTLEKYPDTLLGSTEKEFFYDDDTKEYFFDRDPEIFRHILNFYRTGKLHYPRHECISAYDDELAF 80

                         90       100
                 ....*....|....*....|..
gi 767904241 121 YGILPEIIGDCCYEEYKDRKRE 142
Cdd:cd18380   81 FGILPEIIGDCCYEDYRDRKRE 102

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in voltage-gated potassium (Kv) channels and potassium channel tetramerization domain-containing (KCTD) proteins; This family includes two protein groups: voltage-gated potassium (Kv) channels and potassium channel tetramerization domain-containing (KCTD) proteins. Kv channels are membrane proteins with fundamental physiological roles. They are responsible for a variety of electrical phenomena, such as the repolarization of the action potential, spike frequency adaptation, synaptic repolarization, and smooth muscle contraction. 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. All family members contain the BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif that facilitates homodimerization or heterodimerization.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767904241  42 IVLNVSGRRFQTWRTTLERYPDTLLGSTEK---EFFFNEDTKEYFFDRDPEVFRCVLNFYRTGKLHYPRYECISAYDDEL 118
Cdd:cd18187    1 VVLNVSGTRFVTNRQTLTRHPDTLLGRMFKpgrEFTFPNETGEYFIDRDPTVFRTILNYYRTGKLNCPDGISIPDLREEC 80

                 ...
gi 767904241 119 AFY 121
Cdd:cd18187   81 DFY 83

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 767904241  42 IVLNVSGRRFQTWRTTLERYPDTLLGS-TEKEFFFNEDTKEYFFDRDPEVFRCVLNFYRTGKLHYPRYECISAYDDELAF 120
Cdd:cd18317    1 VVLNVGGTRFELSRSTLLRFPDTRLGKlAKESHAYDESTNEYFFDRNPEVFEAILDYYRTGELHLPSNVCPASFKEELEF 80

                 ..
gi 767904241 121 YG 122
Cdd:cd18317   81 WG 82

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in KCNC/Kv3 subfamily of Shaw-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 four alpha subunit members, Kv3.1 (KCNC1), Kv3.2 (KCNC2), Kv3.3 (KCNC3), and Kv3.4 (KCNC4), which are orthologs of the Shaw gene in Drosophila. Unlike other Kv subfamilies, Kv3 channels typically open only at positive potentials and both, activation and deactivation, in response to changes in voltage are very rapid. They are uniquely associated with the ability of certain neurons to fire action potentials and to release neurotransmitter at high rates of up to 1,000 Hz. Kv3/KCNC 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 767904241  42 IVLNVSGRRFQTWRTTLERYPDTLLGS-TEKE---FFFNEDTKEYFFDRDPEVFRCVLNFYRTGKLHYPRYECISAYDDE 117
Cdd:cd18379    1 IVINVGGVRHETYKSTLRNLPDTRLAWlTETEasaFDYDPVTGEFFFDRHPGVFAQILNYYRTGKLHCPADVCGPLFEEE 80

                         90       100
                 ....*....|....*....|....*...
gi 767904241 118 LAFYGILPEIIGDCCYEEYkdRKRENAE 145
Cdd:cd18379   81 LAFWGIDETQIEPCCWMTY--RQHRDAQ 106

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel protein Shaw; Shaw, also called Shaw2, is a 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. Shaw 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 767904241  39 DELIVLNVSGRRFQTWRTTLERYPDTLLGS-TEKEFFFNEDTKEYFFDRDPEVFRCVLNFYRTGKLHYPRYECISAYDDE 117
Cdd:cd18416    1 ENRVVLNVGGIRHETYKATLKKIPATRLSRlTEALANYDPVLNEYFFDRHPGVFAQILNYYRTGKLHYPTDVCGPLFEEE 80

                         90
                 ....*....|....*....
gi 767904241 118 LAFYGILPEIIGDCCYEEY 136
Cdd:cd18416   81 LEFWGLDANQVEPCCWMTY 99

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily C members KCNC2 and KCNC4; KCNC2, also called Shaw-like potassium channel or voltage-gated potassium channel Kv3.2, is a delayed rectifier voltage-gated potassium channel that mediates transmembrane potassium transport in excitable membranes, primarily in the brain. It contributes to the regulation of the fast action potential repolarization and in sustained high-frequency firing in neurons of the central nervous system. KCNC4, also called KSHIIIC or voltage-gated potassium channel subunit Kv3.4, is a novel high-voltage-activating, tetraethylammonium (TEA)-sensitive, type-A potassium channel that mediates the voltage-dependent potassium ion permeability of excitable membranes. It plays a pivotal role in oxidative stress-related neural cell damage as an oxidation-sensitive channel. 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. KCNC2 and KCNC4 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 767904241  39 DELIVLNVSGRRFQTWRTTLERYPDT---LLGSTEKEFFFNEDT-------------KEYFFDRDPEVFRCVLNFYRTGK 102
Cdd:cd18415    1 NERIILNVGGTRHETYRSTLKTLPGTrlaLLASSDPQGDCLTQCsqvggsdgspgggNEFFFDRHPGVFAYVLNYYRTGK 80

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|...
gi 767904241 103 LHYPRYECISAYDDELAFYGILPEIIGDCCYEEYkdRKRENAE 145
Cdd:cd18415   81 LHCPADVCGPLFEEELAFWGIDETDVEPCCWMTY--RQHRDAE 121

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 767904241    42 IVLNVSGRRFQTWRTTLERYPDTLLGSTEKEFFFNEDTKEYFFDRDPEVFRCVLNFYRTGKLHYPRyECISAYDDELAFY 121
Cdd:smart00225   2 VTLVVGGKKFHAHKAVLAAHSPYFKALFSSDFKESDKSEIYLDDVSPEDFRALLNFLYTGKLDLPE-ENVEELLELADYL 80

                           90
                   ....*....|....*...
gi 767904241   122 GIlPEIIGDCCYEEYKDR 139
Cdd:smart00225  81 QI-PGLVELCEEFLLKLL 97

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily A member 7 (KCNA7); KCNA7, also called voltage-gated potassium channel subunit Kv1.7, 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. KCNA7 plays an important role in the repolarization of cell 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. KCNA7 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 767904241  40 ELIVLNVSGRRFQTWRTTLERYPDTLLGS-TEKEFFFNEDTKEYFFDRDPEVFRCVLNFYRT-GKLHYPRYECISAYDDE 117
Cdd:cd18408    6 ERVVLNVAGLRFETRARTLGRFPDTLLGDpARRGRFYDDRRREYFFDRHRPSFDAVLYYYQSgGRLRRPAHVPLDVFLEE 85

                         90
                 ....*....|..
gi 767904241 118 LAFYGILPEIIG 129
Cdd:cd18408   86 VAFYGLGAAALA 97

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 767904241  42 IVLNVSGRRFQTWRTTLERYPDTLLG---STEKEFFF------NEDTKEYFFDRDPEVFRCVLNFYRTGKLHYPRYECIS 112
Cdd:cd18424    1 FTINVGGSRFVLSQQVLSSHPETRLGklaVSVRDSVLelcddaNFVDNEYFFDRSSQAFKYIMNYYKTGHLHVMEELCAI 80

                         90       100
                 ....*....|....*....|....*...
gi 767904241 113 AYDDELAFYGILPEIIGDCCYEEYKDRK 140
Cdd:cd18424   81 SFLQEIEYWGIDELSIDSCCRERYYRRK 108

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in KCNG/Kv6 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 Kv6, also known as subfamily G, includes KCNG1 (Kv6.1), KCNG2 (Kv6.2 or KCNF2), KCNG3 (Kv6.3) and KCNG4 (Kv6.4), which are regulatory alpha subunits and do not form functional channels on their own. KCNG1 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, 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. KCNG3, also called voltage-gated potassium channel subunit Kv10.1, is an electrically silent modulatory subunit that can form functional heterotetrameric channels with KCNB1, and further promotes a reduction in the rate of activation and inactivation of the delayed rectifier voltage-gated potassium channel KCNB1. KCNG4 is a silent voltage-gated potassium (KvS) channel subunit that can form functional heterotetrameric channels with KCNB1, and further modulates the delayed rectifier voltage-gated potassium channel activation and deactivation rates of KCNB1.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767904241  42 IVLNVSGRRFQTWRTTLERYPDTLLG-----STEKEFF-----FNEDTKEYFFDRDPEVFRCVLNFYRTGKLHYPRYECI 111
Cdd:cd18382    1 VIINVGGARYSLPWSTLDRFPLTRLSrlkacRSEDDILrvcddYDVERNEFFFDRSPEAFGVILLFLRAGKLRLLREMCA 80

                         90       100
                 ....*....|....*....|....*...
gi 767904241 112 SAYDDELAFYGILPEIIGDCCYEEYKDR 139
Cdd:cd18382   81 LSFQEELAYWGIEEAHLERCCKRRLLRR 108

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 767904241  42 IVLNVSGRRFQTWRTTLERYPDTLL--------GSTEKEFFFNED----TKEYFFDRDPEVFRCVLNFYRTGKLHYPRYE 109
Cdd:cd18381    3 IVVNVGGVRQVLYGDVLNRYPETRLaellnclsGGYDAIFSLCDDydpgKREFYFDRDPDAFKCIIEVYYYGEIHMKKGI 82

                         90       100       110
                 ....*....|....*....|....*....|...
gi 767904241 110 CISAYDDELAFYGILPEIIGDCCYEEYKDRKRE 142
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 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 767904241  42 IVLNVSGRRFQTWRTTLERYPDTLLG------STEKEFFFNED----TKEYFFDRDPEVFRCVLNFYRTGKLHYPRYECI 111
Cdd:cd18427    2 ISINVGGFKKRLRSHTLLRFPETRLGrllscrSKESILELCDDyddtKNEFYFDRNPELFPYVLHFYNTGKLHVMGELCV 81

                         90       100
                 ....*....|....*....|....*
gi 767904241 112 SAYDDELAFYGILPEIIGDCCYEEY 136
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 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 767904241  40 ELIVLNVSGRRFQTWRTTLERYPDTLLGSTEKEF-FFNEDTKEYFFDRDPEVFRCVLNFYRT-GKLHYPRYECISAYDDE 117
Cdd:cd18406    1 ERVIINIAGLRFETQLGTLNQFPDTLLGDPDKRMrYFDPLRNEYFFDRNRPSFDGILYFYQSgGKIRRPVNVSIDVFADE 80

                 ....
gi 767904241 118 LAFY 121
Cdd:cd18406   81 IRFY 84

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily A members 2 (KCNA2) and 3 (KCNA3); KCNA2 is also called NGK1, voltage-gated K(+) channel HuKIV, voltage-gated potassium channel HBK5, or voltage-gated potassium channel subunit Kv1.2. KCNA3 is also called HGK5, HLK3, HPCN3, voltage-gated K(+) channel HuKIII, or voltage-gated potassium channel subunit Kv1.3. KCNA2 and KCNA3 mediate 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. KCNA2 primarily functions in the brain and the central nervous system, but also in the cardiovascular system. It prevents aberrant action potential firing and regulates neuronal output. 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. KCNA2 and KCNA3 are alpha subunits that form functional homo- or hetero-tetrameric channels (with other Kv1/KCNA 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 767904241  40 ELIVLNVSGRRFQTWRTTLERYPDTLLGSTEKEF-FFNEDTKEYFFDRDPEVFRCVLNFYRT-GKLHYPRYECISAYDDE 117
Cdd:cd18403    1 ERVVINISGLRFETQLKTLAQFPETLLGDPKKRMrYFDPLRNEYFFDRNRPSFDAILYYYQSgGRLRRPVNVPLDIFSEE 80

                         90
                 ....*....|.
gi 767904241 118 LAFYGILPEII 128
Cdd:cd18403   81 IRFYELGEEAM 91

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily A member 10 (KCNA10); KCNA10, also called voltage-gated potassium channel subunit Kv1.8, is a cyclic nucleotide-gated, voltage-activated 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. KCNA10 is expressed in proximal tubular cells, glomerular and vascular endothelial cells, as well as in vascular smooth muscle cells. It may facilitate proximal tubular sodium absorption by stabilizing cell membrane voltage. The channel activity is up-regulated by cAMP. 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. KCNA10 is an alpha subunit that forms functional homotetrameric channels 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 767904241  42 IVLNVSGRRFQTWRTTLERYPDTLLGSTEKEF-FFNEDTKEYFFDRDPEVFRCVLNFYRT-GKLHYPRYECISAYDDELA 119
Cdd:cd18409    3 VIINIAGLRFETQLKTLDQFPDTLLGDPEKRMkYFDSMRNEYFFDRNRPSFDGILYYYQSgGKIRRPANVPLDVFADEII 82

                 ..
gi 767904241 120 FY 121
Cdd:cd18409   83 FY 84

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily G member 4 (KCNG4); KCNG4, also called voltage-gated potassium channel subunit Kv6.4, is a silent voltage-gated potassium (KvS) channel subunit 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. 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. KCNG4 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 767904241  42 IVLNVSGRRFQTWRTTLERYPDTLLG-----STEKEFF-----FNEDTKEYFFDRDPEVFRCVLNFYRTGKLHYPRYECI 111
Cdd:cd18423    4 IIINVGGIKYLMPWSTLDEFPLTRLGklkfcSSYEEIVqicddYDEDTNEFFFDRNPCAFRMIVSFLAAGKLRLLREMCA 83

                         90       100
                 ....*....|....*....|..
gi 767904241 112 SAYDDELAFYGILPEIIGDCCY 133
Cdd:cd18423   84 LSFQEELTYWGIEEANLERCCL 105

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 767904241  42 IVLNVSGRRFQTWRTTLERYPDTLLG-----STEKEFF-----FNEDTKEYFFDRDPEVFRCVLNFYRTGKLHYPRYECI 111
Cdd:cd18426    1 ININVGGLKRRLSSSTLSKFPDTRLGrllscDSEESILqicddYDVSAKEFYFDRNPGLFPYVLHFYQTGKLHIMEELCV 80

                         90       100
                 ....*....|....*....|....*
gi 767904241 112 SAYDDELAFYGILPEIIGDCCYEEY 136
Cdd:cd18426   81 FSFSQEIEYWGINEFFLDSCCSYRY 105

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 767904241  39 DELIVLNVSGRRFQTWRTTLERYPDT----LLG---STEKefffnEDTKEYFFDRDPEVFRCVLNFYRTGKLHYPRYEcI 111
Cdd:cd18363    1 GDIINLNVGGKRFSTSRQTLTWIPDSfftsLLSgriSSLK-----DETGAIFIDRDPKLFSIILNYLRTKEIDLRNVD-I 74

                         90
                 ....*....|..
gi 767904241 112 SAYDDELAFYGI 123
Cdd:cd18363   75 SSLRHEAEFYGI 86

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 767904241  40 ELIVLNVSGRRFQTWRTTLERYPDTLLGSTEKEF-FFNEDTKEYFFDRDPEVFRCVLNFYRT-GKLHYPRYECISAYDDE 117
Cdd:cd18402    9 ERVVINIAGLRFETQLKTLAQFPNTLLGNPKKRMrYFDPLRNEYFFDRNRPSFDAILYYYQSgGRLRRPVNVPLDMFSEE 88

                 ....
gi 767904241 118 LAFY 121
Cdd:cd18402   89 IKFY 92

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 21 (KCTD21); KCTD21, also calledz KCTD containing, Cullin3 adaptor, suppressor of Hedgehog 2 (KCASH2), is a BTB/POZ domain-containing protein that functions as a substrate-specific adaptor of cullin-3, promoting the ubiquitination and degradation of histone deacetylase HDAC1, thereby inhibiting the deacetylation-mediated transcriptional activation of the Hedgehog effectors Gli1 and Gli2. 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 767904241  42 IVLNVSGRRFQTWRTTLERYPDTLLGST-EKEFFFNEDTKEYFF-DRDPEVFRCVLNFYRTGKLHYPR-YECISAYDDEL 118
Cdd:cd18395    3 ITLNVGGKLYTTSLATLTRYPDSMLGAMfSGKFPTKKDSQGNCFiDRDGKIFRYILNFLRTSHLDLPEdFQEMGLLKREA 82

                 ....*....
gi 767904241 119 AFYGILPEI 127
Cdd:cd18395   83 DFYQIQPLI 91

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 767904241  38 QDELIVLNVSGRRFQTWRTTLERYPDTLLGSTEKEFFFNE----------DTKEYFFDRDPEVFRCVLNFYRTGKLHYPR 107
Cdd:cd18421    2 RTRHVIINVGGIKYRIPWTTLEEFPLTRLGQLKSCNNFDEimdicddydvTCNEFFFDRNPCAFRTILTFLRAGKLRLLR 81

                         90       100       110
                 ....*....|....*....|....*....|..
gi 767904241 108 YECISAYDDELAFYGILPEIIGDCCYEEYKDR 139
Cdd:cd18421   82 EMCALSFQEELLYWGIEEENLEWCCRRRLLQK 113

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 767904241  44 LNVSGRRFQTWRTTLERYPDTLLG----STEKEFF------FNEDTKEYFFDRDPEVFRCVLNFYRTGKLHYPRYECISA 113
Cdd:cd18425    3 INVGGTSYQISYRVAASYPKTRIGrlatYTDRSRKldlcddYNVQNDEYFFDRDPAVFHHIYNFYRTGVLWVKDELCPRN 82

                         90       100
                 ....*....|....*....|....*.
gi 767904241 114 YDDELAFYGILPEIIGDCCYEEYKDR 139
Cdd:cd18425   83 FLEEINYWGVRIKNTPRCCRISFEER 108

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 7 (KCTD7); KCTD7 is a BTB/POZ domain-containing protein that has an impact on K+ fluxes, neurotransmitter synthesis, and neuronal function. It functions as a regulator of potassium conductance in neurons, and is involved in the control of excitability of cortical neurons. Mutations in KCTD7 may cause progressive myoclonus epilepsy (PME). 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 767904241  40 ELIVLNVSGRRFQTWRTTLERYPDTLLGSTEKEFFFNEDTKE--YFFDRDPEVFRCVLNFYRTGKLHyPRYECISAYdDE 117
Cdd:cd18366    4 EVVPLNVGGMHFTTRLSTLRKYEDSMLAAMFSGRHHIPKDSEgrYFIDRDGSYFGYILNFLRDGDLP-PRERARAVY-KE 81

                 ....*...
gi 767904241 118 LAFYGILP 125
Cdd:cd18366   82 AQYYGIGP 89

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 9 (KCTD9); KCTD9 is a BTB/POZ domain-containing protein that contributes to liver injury through NK cell activation during hepatitis B virus-induced acute-on-chronic liver failure. It functions as a substrate-specific adaptor of a BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex, which mediates the ubiquitination of target proteins, leading to their degradation by the proteasome. 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 KCTD9 BTB domain forms a pentameric structure.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767904241  40 ELIVLNVSGRRFQTWRTTLERY-PDTLLGstekEFFFNEDTKE--------YFFDRDPEVFRCVLNFYRTGKLhypryec 110
Cdd:cd18368    1 DWIKLNVGGRIFTTTRSTLVKKePDSMLA----RMFSDDSTWPssrdengaYLIDRSPEYFEPILNYLRHGQL------- 69

                         90
                 ....*....|....*.
gi 767904241 111 isAYDDELAFYGILPE 126
Cdd:cd18368   70 --ILNDGLNPLGVLEE 83

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing proteins, KCTD8, KCTD12, KCTD16 and similar proteins; This subfamily of KCTD proteins includes KCTD8, KCTD12 (also called predominantly fetal expressed T1 domain/Pfetin), and KCTD16. They act as auxiliary subunits of GABAB receptors associated with mood disorders. KCTD8 interacts as a tetramer with GABRB1 and GABRB2. KCTD12 regulates agonist potency and kinetics of GABAB receptor signaling. It promotes tumorigenesis by facilitating CDC25B/CDK1/Aurora A-dependent G2/M transition. KCTD16 interacts with amyloid beta precursor protein (APP), a type I transmembrane protein involved in a variety of cellular processes such as cell adhesion, and axon guidance. 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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 767904241  40 ELIVLNVSGRRFQTWRTTLERYPDTLLGSTEKEFFFNE---DTK-EYFFDRDPEVFRCVLNFYRTGKLHYP 106
Cdd:cd18367    3 EIVELNVGGQVYTTSLSTLIKDPDSLLGRMFSGKNRQElarDSKgRYFLDRDGVLFRYILDYLRNQKLVLP 73

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily G member 3 (KCNG3); KCNG3, also called voltage-gated potassium channel subunit Kv6.3 or voltage-gated potassium channel subunit Kv10.1, is an electrically silent modulatory subunit that can form functional heterotetrameric channels with KCNB1 (also known as Kv2.1), and further promotes a reduction in the rate of activation and inactivation of the delayed rectifier voltage-gated potassium channel 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. KCNG3 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 767904241  42 IVLNVSGRRFQTWRTTLERYPDTLLG-----STEKEFF-----FNEDTKEYFFDRDPEVFRCVLNFYRTGKLHYPRYECI 111
Cdd:cd18422    1 VTLNVGGTRYSFSREVIKDFPLRRVSrlhgcLSEQDVLevcddYDRERNEYFFDRHSEAFGFIMLYVKYGKLRFVPQMCE 80

                         90       100
                 ....*....|....*....|....*...
gi 767904241 112 SAYDDELAFYGILPEIIGDCCYEEYKDR 139
Cdd:cd18422   81 LSFYNEMIYWGLERSHLEYCCQRRLDDR 108