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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 74708977   1 MLGAMFRAGTPMPPNLNSQGGGHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRAEADFYQ 65
Cdd:cd18370  24 MLGAMFRAGTPIPPNLNMQGGGHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRAEADFYQ 88

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 74708977   1 MLGAMFRAGTPMPPNLNSQGGGHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRAEADFYQ 65
Cdd:cd18370  24 MLGAMFRAGTPIPPNLNMQGGGHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRAEADFYQ 88

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
                  ....*....|....*....|....*....|....*....|....*....|
gi 74708977    22 GHYFIDRDGKAFRHILNFLRLGrLDLPRGYGETAL-LRAEADFYQIRPLL 70
Cdd:pfam02214  41 NEYFFDRSPKHFETILNFYRTG-GKLHRPEEVCLDeFLEEAEFYGLDELA 89

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 74708977   1 MLGAMFRAGTPMPPNLNSQGGGHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRAEADFYQ 65
Cdd:cd18370  24 MLGAMFRAGTPIPPNLNMQGGGHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRAEADFYQ 88

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing proteins, KCTD6, KCTD21 and similar proteins; KCTD6, also called KCASH3 (KCTD containing, Cullin3 adaptor, suppressor of Hedgehog 3), is a substrate-specific adaptor of cullin-3, effectively regulating protein levels of the muscle small ankyrin-1 isoform 5 (sAnk1.5). KCTD21, also called KCASH2, 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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 74708977   1 MLGAMFraGTPMPPNLNSQGggHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRAEADFYQIRPLLDAL 73
Cdd:cd18365  26 MLGAMF--SGSMPTTRDDQG--NYFIDRDGTLFRYILNFLRSSQLSLPEDFKEYDLLLREADFYQIEPLIEAL 94

BTB/POZ domain-containing protein KCTD11/21 C-terminus; This family represents the C-terminal region of BTB/POZ domain-containing protein KCTD11 (known as REN: EGF-, NGF- and retinoic acid-responsive gene) and one homolog, a member of KCTD containing, Cullin3 adaptor, suppressor of Hedgehog (KCASH) family, KCASH2-KCTD21 protein. They share high similarity and a BTB domain responsible for oligomerization and formation of a Cullin3 ubiquitin ligase complex, specific expression in brain and cerebellum where they have a role in neuronal differentiation, and suppressor activity on acetylation-dependent Hedgehog/Gli signalling through ubiquitination and degradation of histone deacetylase 1. These proteins have been described as tumor suppressors that inhibit medulloblastoma growth by antagonizing Hedgehog signalling.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 74708977    88 ALLHADVDVSPRLVHFSARRGPHHYELSSVQVDTFRANLFCTDSECLGALRAR-FGVASGDRA------EGSPHFHLEWA 160
Cdd:pfam19329   4 AMLNISLDQKMQTVHFTVREAPQIYSLSSSTMEVFNANIFCTSGLFLKLLGSQlCYFFNGNLSpicselEDQNHLTLQWV 83

                          90       100       110       120       130       140       150
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 74708977   161 PRPVELPEVEYGRLGLQPLWTggPGERREVVGTPSFLEEVLRVALEHGFRLDSVFPDPEDLLNSRSLRFVRH 232
Cdd:pfam19329  84 AAVEGLPEEEYTLQNLKRLWV--FPANKQINSFQAFVEEVLKIAMNDGFCMDSSHPSSLDFMNNKIIRLIRY 153

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 74708977   2 LGAMFRAGTPMPPNLNSQgggHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRAEADFYQIRPLLDAL 73
Cdd:cd18361  25 LGKLFNGSIPIVLDSLKQ---HYFIDRDGKMFRHILNFLRTSKLLLPDDFTEFDLLYEEARYYELQPMVKQL 93

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Arabidopsis thaliana FH protein interacting protein FIP2 and similar proteins; FIP2 may act as a substrate-specific adaptor of an E3 ubiquitin-protein ligase complex (CUL3-RBX1-BTB) which mediates the ubiquitination and subsequent proteasomal degradation of target proteins. It contains a 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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 74708977   1 MLGAMFRAGTPMPPNLNsqggGHYFIDRDGKAFRHILNFLRLGRLDLP----RGYGEtalLRAEADFYQIRPL 69
Cdd:cd18376  24 MLAAMFSGRHSLKKDED----GSYFIDRDGTHFRHILNYLRDGEVKIPtedrSVLKE---LLEEAEYYQLRGL 89

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel regulatory protein (KCNRG); KCNRG, also called potassium channel regulator or protein CLLD4, is an endoplasmic reticulum (ER)-associated tumor suppressor that regulates Kv1 family potassium channel proteins by retaining a fraction of the channels in endomembranes. It contains a 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
                ....*....|....*....|....*....|....*....|....*....|...
gi 74708977  21 GGHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRAEADFYQIRPLLDAL 73
Cdd:cd18375  42 NGQFFVDRDGSLFSYILDYLRTGQLTLPTEFSDYNRLAREAEFYGLYSLADLL 94

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 15 (KCTD15); 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, closely related to KCTD15, form pentamers.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 74708977  23 HYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRAEADFYQIRPLldaLRELE 77
Cdd:cd18388  46 HYFIDRDGEIFRYILSFLRTSKLLLPEDFKDFNLLYEEAKYYQLQPM---VKELE 97

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 74708977   1 MLGAMFRAGTPMPPNLNsqggGHYFIDRDGKAFRHILNFLRLGrlDLPRGYGETALLRaEADFYQIRPLLD 71
Cdd:cd18366  29 MLAAMFSGRHHIPKDSE----GRYFIDRDGSYFGYILNFLRDG--DLPPRERARAVYK-EAQYYGIGPLIE 92

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing proteins, KCTD10 (BACURD3), KCTD13 (BACURD1), and TNFAIP1 (BACURD2); This subfamily of KCTD proteins, also called the BTB/POZ domain-containing adapter for CUL3-mediated RhoA degradation protein (BACURD) subfamily, includes KCTD10 (BACURD3), KCTD13 (BACURD1), and TNFAIP1 (BACURD2). KCTD10 is a BTB/POZ domain-containing protein that interacts with proliferating cell nuclear antigen (PCNA) and polymerase delta, and participates in DNA repair, DNA replication, and cell-cycle control. Its down-regulation could inhibit cell proliferation. KCTD10 also plays crucial roles in embryonic angiogenesis and heart development in mammals by negatively regulating the Notch signaling pathway. KCTD13 is a BTB/POZ domain-containing protein that may function as a substrate-specific adaptor of a BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex that mediates the ubiquitination of RhoA, leading to its degradation by the proteasome, thereby regulating the actin cytoskeleton and cell migration. TNFAIP1, also called protein B12, is a BTB/POZ domain-containing protein that is involved in DNA replication, DNA damage repair, cell apoptosis, and is implicated in human diseases including cancer, Alzheimer's disease (AD) and type 2 diabetic nephropathy. 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. KCTD10 and KCTD13 BTB domains form a novel two-fold symmetric tetramer that is distinct from the tetramer formed by voltage-gated potassium (Kv) channels.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 74708977   1 MLGAMFRAGTpmppNLNSQGGGHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRAEADFYQIRPLLDA 72
Cdd:cd18369  23 MLRAMFSGRM----EVLTDSEGWILIDRCGKHFGTILNYLRDGSVPLPESRRELAELLAEAKYYLVQGLVEQ 90

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 14 (KCTD14); KCTD14 is a BTB/POZ domain-containing protein with 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 74708977  13 PPNLNSQGGGHYFIDRDGKAFRHILNFLRLGrlDLPRGYGETalLRAEADFYQIRPLLDALRE 75
Cdd:cd18371  35 QPKLRTDSEGRYFIDRDGTYFRYILEYLRTN--QVPTQHIQE--VYKEALFYDIEPLVKLLEE 93

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 12 (KCTD12); KCTD12, also called predominantly fetal expressed T1 domain (Pfetin), is a BTB/POZ domain-containing protein that is an auxiliary subunit of GABAB receptors associated with mood disorders. It regulates agonist potency and kinetics of GABAB receptor signaling. It promotes tumorigenesis by facilitating CDC25B/CDK1/Aurora A-dependent G2/M transition. It also regulates colorectal cancer cell stemness through the ERK pathway. 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 74708977   1 MLGAMFRAGTPMppNLNSQGGGHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRAEADFYQIRPLLDAL 73
Cdd:cd18397  28 LLWHMFSQQKPG--ELARDSKGRFFLDRDGFLFRYILDYLRDLQLVLPDYFPERSRLQREAEFFQLPELVKRL 98

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
                   ....*....|....*....|....*....|....*....|....*....
gi 74708977     24 YFIDRDGKAFRHILNFLRLGRLDLPRGYGEtaLLRAEADFYQIRPLLDA 72
Cdd:smart00225  42 YLDDVSPEDFRALLNFLYTGKLDLPEENVE--ELLELADYLQIPGLVEL 88

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in tumor necrosis factor, alpha-induced protein 1, endothelial (TNFAIP1); TNFAIP1, also called BTB/POZ domain-containing adapter for CUL3-mediated RhoA degradation protein 2 (BACURD2), or protein B12, is a BTB/POZ domain-containing protein that is involved in DNA replication, DNA damage repair and cell apoptosis, and is implicated in human diseases including cancer, Alzheimer's disease (AD) and type 2 diabetic nephropathy. 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 BTB domains of other BACURD subfamily members, KCTD10 and KCTD13, form a novel two-fold symmetric tetramer that is distinct from the tetramer formed by voltage-gated potassium (Kv) channels.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 74708977   1 MLGAMFRAGTpmppNLNSQGGGHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRAEADFYQIRPLLD 71
Cdd:cd18401  27 MLKAMFSGRM----EVLTDKEGWILIDRCGKHFGTILNYLRDDTVALPKSRQEIKELMAEAKYYLIQGLVD 93

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
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 74708977  22 GHYFIDRDGKAFRHILNFLRLGRLDlPRGYGETALLRaEADFYQIRPLLDALR---ELEAS 79
Cdd:cd18393  44 GAIFIDRDPTVFAPILNFLRTKELD-PRGIHVSLLLH-EAQFYGITPLVRRLQlceELDRS 102

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein KCTD8; KCTD8, a BTB/POZ domain-containing protein, is an auxiliary subunit of GABA-B receptors that determine the pharmacology and kinetics of the receptor response. It interacts as a tetramer with GABRB1 and GABRB2. 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
                ....*....|....*....|....*....|....*....|....*....|..
gi 74708977  22 GHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRAEADFYQIRPLLDAL 73
Cdd:cd18396  48 GRFFIDRDGFLFRYVLDYLRDKQLALPDHFPEKERLLREAEYFQLGDLVKLL 99

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 5 (KCTD5); KCTD5 is a BTB/POZ domain-containing protein that functions as a substrate adaptor for cullin3 based ubiquitin E3 ligases. It 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. 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 forms pentamers mediated by its BTB domain.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 74708977  14 PNLNSQGG--GHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRaEADFYQIRPLL----DALRE 75
Cdd:cd18390  39 PDLDSDKDetGAYLIDRDPTYFGPVLNYLRHGKLVINKDLAEEGVLE-EAEFYNITSLIklvkDKIRE 105

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
                ....*....|....*....|....*....|....*....|....*....|...
gi 74708977  14 PNLNSQ--GGGHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLrAEADFY 64
Cdd:cd18362  34 PDLPSDkdETGAYLIDRDPTYFGPILNYLRHGKLIIDKDLAEEGVL-EEAEFY 85

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.

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                ....*....|....*....|....*....|....*....|....*..
gi 74708977  22 GHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETAlLRAEADFYQIRP 68
Cdd:cd18380  40 KEYFFDRDPEIFRHILNFYRTGKLHYPRHECISA-YDDELAFFGILP 85

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
                ....*....|....*....|....*....|....*....|....*
gi 74708977  24 YFIDRDGKAFRHILNFLRLGRLDLPRgYGETALLRAEADFYQIRP 68
Cdd:cd18419  77 YFFDRDPEVFRCVLNFYRTGKLHYPR-YECISAYDEELAFYGILP 120

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 10 (KCTD10); KCTD10, also called BTB/POZ domain-containing adapter for CUL3-mediated RhoA degradation protein 3 (BACURD3), is a BTB/POZ domain-containing protein that interacts with proliferating cell nuclear antigen (PCNA) and polymerase delta, and participates in DNA repair, DNA replication, and cell-cycle control. Its down-regulation could inhibit cell proliferation. KCTD10 also plays crucial roles in embryonic angiogenesis and heart development in mammals by negatively regulating the Notch signaling pathway. Furthermore, KCTD10 may function 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 KCTD10 BTB domain forms a novel two-fold symmetric tetramer that is distinct from the tetramer formed by voltage-gated potassium (Kv) channels.

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gi 74708977  22 GHYFIDRDGKAFRHILNFLRLGRLDLPRGYGETALLRAEADFYQIRPLLD 71
Cdd:cd18399  48 GWILIDRCGKHFGTILNYLRDGAVPLPESRREIEELLAEAKYYLVQGLVE 97

first BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 19 (KCTD19); KCTD19 is a BTB/POZ domain-containing protein with unclear biological function. It may be a host factor involved in Nef-induced downregulation of MHC-I. Nef is a HIV-1-encoded protein that plays a key role in the development of AIDS. KCTD19 contains two BTB domains. This model corresponds to the first 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.

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gi 74708977  25 FIDRDGKAFRHILNFLRLGRLDLpRGYGETALLRAEADFYQIRPLLDALRELEA 78
Cdd:cd18373  41 FIDRDGFTFRHVHYYLQTSKLSS-SSCSELNLLYEQAAGLQLTSLLQALDNLKE 93

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.

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gi 74708977  24 YFIDRDGKAFRHILNFLRLGRLDLPR 49
Cdd:cd18378  54 YFFDRHPGAFTSILNFYRTGKLHMPE 79