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.

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gi 71998555  18 EKSGCIFIDRSPKHFELILNLMRDGNLWLPETEKELRELCAEANYYQMFGLYNKC 72
Cdd:cd18369  37 DSEGWILIDRCGKHFGTILNYLRDGSVPLPESRRELAELLAEAKYYLVQGLVEQC 91

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.

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gi 71998555  18 EKSGCIFIDRSPKHFELILNLMRDGNLWLPETEKELRELCAEANYYQMFGLYNKC 72
Cdd:cd18369  37 DSEGWILIDRCGKHFGTILNYLRDGSVPLPESRRELAELLAEAKYYLVQGLVEQC 91

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.

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gi 71998555      4 TIFLQKPEHFQPKLEKSGCIFIDRSPKHFELILNLMRDGNLWLPetEKELRELCAEANYYQMFGLYNKCGVKLSTII 80
Cdd:smart00225  23 PYFKALFSSDFKESDKSEIYLDDVSPEDFRALLNFLYTGKLDLP--EENVEELLELADYLQIPGLVELCEEFLLKLL 97

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.

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gi 71998555  18 EKSGCIFIDRSPKHFELILNLMRDGNLWLPETEKELRELCAEANYYQMFGLYNKC 72
Cdd:cd18369  37 DSEGWILIDRCGKHFGTILNYLRDGSVPLPESRRELAELLAEAKYYLVQGLVEQC 91

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.

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gi 71998555  18 EKSGCIFIDRSPKHFELILNLMRDGNLWLPETEKELRELCAEANYYQMFGLYNKCGVKL 76
Cdd:cd18401  41 DKEGWILIDRCGKHFGTILNYLRDDTVALPKSRQEIKELMAEAKYYLIQGLVDMCQAAL 99

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing proteins; The potassium channel tetramerization domain (KCTD) family proteins contain the BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif that facilitates homodimerization or heterodimerization. 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. Some others show Cullin-independent functions including binding and regulation of GABA (gamma-aminobutyric acid) receptors (KCTD8, KCTD12 and KCTD16) and inhibition of AP-2 function (KCTD15). KCTD family BTB domains can adopt a wide range of oligomerization geometries, including homodimerization, tetramerization, and pentamerization.

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gi 71998555  19 KSGCIFIDRSPKHFELILNLMRDGNLWLPETEKELRELCAEANYY 63
Cdd:cd18316  39 EDGSIFIDRDPELFRHILNFLRTGKLPLPSDFVELEELLAEAEFY 83

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.

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gi 71998555    18 EKSGCIFIDRSPKHFELILNLMRDGnLWLPET-EKELRELCAEANYYQMFGLY 69
Cdd:pfam02214  38 DDTNEYFFDRSPKHFETILNFYRTG-GKLHRPeEVCLDEFLEEAEFYGLDELA 89

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.

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gi 71998555      4 TIFLQKPEHFQPKLEKSGCIFIDRSPKHFELILNLMRDGNLWLPetEKELRELCAEANYYQMFGLYNKCGVKLSTII 80
Cdd:smart00225  23 PYFKALFSSDFKESDKSEIYLDDVSPEDFRALLNFLYTGKLDLP--EENVEELLELADYLQIPGLVELCEEFLLKLL 97

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.

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gi 71998555  18 EKSGCIFIDRSPKHFELILNLMRDGNLWLPETEKELRELCAEANYYQM 65
Cdd:cd18365  40 DDQGNYFIDRDGTLFRYILNFLRSSQLSLPEDFKEYDLLLREADFYQI 87

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.

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gi 71998555   1 MLLTIFLQKpehFQPKLEKSGCIFIDRSPKHFELILNLMRDGNLWLPETEKELRELCAEANYYQM 65
Cdd:cd18395  26 MLGAMFSGK---FPTKKDSQGNCFIDRDGKIFRYILNFLRTSHLDLPEDFQEMGLLKREADFYQI 87

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 6 (KCTD6); KCTD6, also called KCTD containing, Cullin3 adaptor, suppressor of Hedgehog 3 (KCASH3), is a BTB/POZ domain-containing protein that functions as a substrate-specific adaptor of cullin-3, regulating protein levels of the muscle small ankyrin-1 isoform 5 (sAnk1.5) as well as suppressing histone deacetylase and Hedgehog activity in medulloblastoma. 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 71998555  13 FQPKLEKSGCIFIDRSPKHFELILNLMRDGNLWLPETEKELRELCAEANYYQM 65
Cdd:cd18394  37 FPTARDSQGNYFIDRDGPLFRYILNFLRTSELTLPVDFKEFDLLRKEADFYQI 89

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.

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gi 71998555  20 SGCIFIDRSPKHFELILNLMRDGNLWLPETekELRELCAEANYY 63
Cdd:cd18363  43 TGAIFIDRDPKLFSIILNYLRTKEIDLRNV--DISSLRHEAEFY 84

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.

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gi 71998555  12 HFQPKlEKSGCIFIDRSPKHFELILNLMRDGNlwLPETEkELRELCAEANYYQMFGL 68
Cdd:cd18366  38 HHIPK-DSEGRYFIDRDGSYFGYILNFLRDGD--LPPRE-RARAVYKEAQYYGIGPL 90

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.

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gi 71998555  20 SGCIFIDRSPKHFELILNLMRDGNLWLPETEKELRELCAEANYYQMFGL 68
Cdd:cd18375  42 NGQFFVDRDGSLFSYILDYLRTGQLTLPTEFSDYNRLAREAEFYGLYSL 90

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 2 (KCTD2); KCTD2 is a BTB/POZ domain-containing protein that functions as an adaptor of Cullin3 E3 ubiquitin ligase. It suppresses gliomagenesis by destabilizing c-Myc. 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 domain, highly similar to KCTD2, form pentamer structures.

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gi 71998555  18 EKSGCIFIDRSPKHFELILNLMRDGNLWLpetEKELRE--LCAEANYYQMFGL 68
Cdd:cd18389  42 DETGAYLIDRDPTYFGPILNYLRHGKLII---NKELAEegVLEEAEFYNIASL 91

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.

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gi 71998555  21 GCIFIDRSPKHFELILNLMRDGNLWLPETEKELRELCAEANYYQM 65
Cdd:cd18396  48 GRFFIDRDGFLFRYVLDYLRDKQLALPDHFPEKERLLREAEYFQL 92

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.

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gi 71998555   1 MLLTIFLQKpehfQPK---LEKSGCIFIDRSPKHFELILNLMRDGNLWLPETEKELRELCAEANYYQM 65
Cdd:cd18397  28 LLWHMFSQQ----KPGelaRDSKGRFFLDRDGFLFRYILDYLRDLQLVLPDYFPERSRLQREAEFFQL 91