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 1831507813  5 VKLDVGGTIFKTSKDTLMKL-DSIFKTMLESGTGVS 39
Cdd:cd18316    1 VKLNVGGTLFTTSRSTLLKDpDSLLAALFSGRWPLP 36

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 1831507813  5 VKLDVGGTIFKTSKDTLMKL-DSIFKTMLESGTGVS 39
Cdd:cd18316    1 VKLNVGGTLFTTSRSTLLKDpDSLLAALFSGRWPLP 36

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 1831507813   5 VKLDVGGTIFKTSKDTLMKLDSIFKTMLESGTGVS 39
Cdd:smart00225  2 VTLVVGGKKFHAHKAVLAAHSPYFKALFSSDFKES 36

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 1831507813  5 VKLDVGGTIFKTSKDTLMKL-DSIFKTMLESGTGVS 39
Cdd:cd18316    1 VKLNVGGTLFTTSRSTLLKDpDSLLAALFSGRWPLP 36

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 1831507813   5 VKLDVGGTIFKTSKDTLMKLDSIFKTMLESGTGVS 39
Cdd:smart00225  2 VTLVVGGKKFHAHKAVLAAHSPYFKALFSSDFKES 36

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 13 (KCTD13); KCTD13, also called BTB/POZ domain-containing adapter for CUL3-mediated RhoA degradation protein 1 (BACURD1), or TNFAIP1-like protein, 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. 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 KCTD13 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 1831507813   2 SETVKLDVGGTIFKTSKDTLMKLDSIFKTMLESGTGVS 39
Cdd:cd18400     1 SKYVKLNVGGSLHYTTVQTLTKQDTMLKAMFSGRVEVL 38

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.

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gi 1831507813  5 VKLDVGGTIFKTSKDTLMKL-DSIFKTMLeSGT 36
Cdd:cd18376    1 VKLNVGGQKFTTTLDTLTKDpDSMLAAMF-SGR 32

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 1831507813  5 VKLDVGGTIFKTSKDTLMKLDSIFKTML 32
Cdd:cd18369    1 VKLNVGGSLHYTTIGTLTKQDTMLRAMF 28

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.

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gi 1831507813  5 VKLDVGGTIFKTSKDTLMK 23
Cdd:cd18362    2 VKLNVGGTYFLTTRTTLCR 20