BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 1 (KCTD1); 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 to various extent. It also functions as a novel inhibitor of the Wnt signaling pathway. Mutations in KCTD1 cause scalp-ear-nipple (SEN) syndrome. The BTB/POZ domain, also known as tetramerization (T1) domain, is a versatile protein-protein interaction motif that facilitates homodimerization or heterodimerization. KCTD family BTB domains can adopt a wide range of oligomerization geometries, including homodimerization, tetramerization, and pentamerization. The KCTD1 BTB domains form pentamers.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  28 SNAPVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTL 107
Cdd:cd18387    1 SNAPVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYSL 80

                         90       100
                 ....*....|....*....|....*
gi 569002937 108 LYEEAKYFQLQPMLLEMERWKQDRE 132
Cdd:cd18387   81 LYEEAKYFQLQPMLLELERWKQDRE 105

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 1 (KCTD1); 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 to various extent. It also functions as a novel inhibitor of the Wnt signaling pathway. Mutations in KCTD1 cause scalp-ear-nipple (SEN) syndrome. The BTB/POZ domain, also known as tetramerization (T1) domain, is a versatile protein-protein interaction motif that facilitates homodimerization or heterodimerization. KCTD family BTB domains can adopt a wide range of oligomerization geometries, including homodimerization, tetramerization, and pentamerization. The KCTD1 BTB domains form pentamers.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  28 SNAPVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTL 107
Cdd:cd18387    1 SNAPVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYSL 80

                         90       100
                 ....*....|....*....|....*
gi 569002937 108 LYEEAKYFQLQPMLLEMERWKQDRE 132
Cdd:cd18387   81 LYEEAKYFQLQPMLLELERWKQDRE 105

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 569002937    32 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPivlDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDfkDYTLLYEE 111
Cdd:smart00225   2 VTLVVGGKKFHAHKAVLAAHSPYFKALFSSDFKE---SDKSEIYLDDVSPEDFRALLNFLYTGKLDLPEE--NVEELLEL 76

                           90
                   ....*....|....*.
gi 569002937   112 AKYFQLQPMLLEMERW 127
Cdd:smart00225  77 ADYLQIPGLVELCEEF 92

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 1 (KCTD1); 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 to various extent. It also functions as a novel inhibitor of the Wnt signaling pathway. Mutations in KCTD1 cause scalp-ear-nipple (SEN) syndrome. The BTB/POZ domain, also known as tetramerization (T1) domain, is a versatile protein-protein interaction motif that facilitates homodimerization or heterodimerization. KCTD family BTB domains can adopt a wide range of oligomerization geometries, including homodimerization, tetramerization, and pentamerization. The KCTD1 BTB domains form pentamers.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  28 SNAPVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTL 107
Cdd:cd18387    1 SNAPVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYSL 80

                         90       100
                 ....*....|....*....|....*
gi 569002937 108 LYEEAKYFQLQPMLLEMERWKQDRE 132
Cdd:cd18387   81 LYEEAKYFQLQPMLLELERWKQDRE 105

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        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  29 NAPVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLL 108
Cdd:cd18388    1 NAPVHIDVGGHMYTSSLATLTKYPDSRISRLFNGTEPIVLDSLKQHYFIDRDGEIFRYILSFLRTSKLLLPEDFKDFNLL 80

                         90
                 ....*....|....*....
gi 569002937 109 YEEAKYFQLQPMLLEMERW 127
Cdd:cd18388   81 YEEAKYYQLQPMVKELERW 99

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        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  30 APVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSlKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLLY 109
Cdd:cd18365    1 DIVNLNVGGVHYTTTLATLTRFPDSMLGAMFSGSMPTTRDD-QGNYFIDRDGTLFRYILNFLRSSQLSLPEDFKEYDLLL 79

                         90
                 ....*....|..
gi 569002937 110 EEAKYFQLQPML 121
Cdd:cd18365   80 READFYQIEPLI 91

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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSlKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLLYEE 111
Cdd:cd18316    1 VKLNVGGTLFTTSRSTLLKDPDSLLAALFSGRWPLPRDE-DGSIFIDRDPELFRHILNFLRTGKLPLPSDFVELEELLAE 79

                 ....
gi 569002937 112 AKYF 115
Cdd:cd18316   80 AEFY 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        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEP--IVLDSlKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLLY 109
Cdd:cd18367    5 VELNVGGQVYTTSLSTLIKDPDSLLGRMFSGKNRqeLARDS-KGRYFLDRDGVLFRYILDYLRNQKLVLPENFPERERLK 83

                         90
                 ....*....|..
gi 569002937 110 EEAKYFQLQPML 121
Cdd:cd18367   84 REAEYFQLPELV 95

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        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPiVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLLYEE 111
Cdd:cd18375    3 VTLNVGGKKFTTRPSTLRRFPDSRLARMLDGKDQ-DFKVVNGQFFVDRDGSLFSYILDYLRTGQLTLPTEFSDYNRLARE 81

                         90
                 ....*....|....*
gi 569002937 112 AKYFQLQPMLLEMER 126
Cdd:cd18375   82 AEFYGLYSLADLLSQ 96

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        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSlKQHYFIDRDGQMFRYILNFLRTSKL---LIPDdfkdytlL 108
Cdd:cd18371    4 VSLNVGGHIYTTTLSTLRKFPGSKLAELFNGQPKLRTDS-EGRYFIDRDGTYFRYILEYLRTNQVptqHIQE-------V 75

                         90
                 ....*....|....*..
gi 569002937 109 YEEAKYFQLQPMLLEME 125
Cdd:cd18371   76 YKEALFYDIEPLVKLLE 92

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 16 (KCTD16); KCTD16 is a BTB/POZ domain-containing protein that is an auxiliary subunit of GABAB receptors associated with mood disorders. It 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        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIGRLF----DGTEPIVLDSlKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTL 107
Cdd:cd18398    5 VELNVGGQVYFTRHATLVSIPHSLLWKMFspkrDTANDLAKDS-KGRFFIDRDGFLFRYILDYLRDRQVVLPDHFPEKGR 83

                         90
                 ....*....|....*..
gi 569002937 108 LYEEAKYFQLqPMLLEM 124
Cdd:cd18398   84 LKREAEYFQL-PDLVKL 99

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        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVL--DSlKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLLY 109
Cdd:cd18397    5 VELNVGGQVYVTRHTTLVSVPDSLLWHMFSQQKPGELarDS-KGRFFLDRDGFLFRYILDYLRDLQLVLPDYFPERSRLQ 83

                         90
                 ....*....|.
gi 569002937 110 EEAKYFQLQPM 120
Cdd:cd18397   84 REAEFFQLPEL 94

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 569002937   32 VHIDVGGHMYTSSLATLTKYPESRIGRLFDgTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTS-KLLIPDDfKDYTLLYE 110
Cdd:pfam02214   1 VKLNVGGTRFETLKSTLTRFPDTRLGRLLE-LECDDYDDDTNEYFFDRSPKHFETILNFYRTGgKLHRPEE-VCLDEFLE 78

                          90
                  ....*....|....
gi 569002937  111 EAKYFQLQPMLLEM 124
Cdd:pfam02214  79 EAEFYGLDELALEL 92

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 569002937  32 VHIDVGGHMYTSSLATLTKY-PESRIGRLF--DGTEPIVLDSlKQHYFIDRDGQMFRYILNFLRTSKLLIpDDFKDYTLL 108
Cdd:cd18368    3 IKLNVGGRIFTTTRSTLVKKePDSMLARMFsdDSTWPSSRDE-NGAYLIDRSPEYFEPILNYLRHGQLIL-NDGLNPLGV 80

                         90
                 ....*....|....*..
gi 569002937 109 YEEAKYFQLQPMLLEME 125
Cdd:cd18368   81 LEEAKFFGIQSLIEILE 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 569002937  34 IDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVL------DSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTL 107
Cdd:cd18424    3 INVGGSRFVLSQQVLSSHPETRLGKLAVSVRDSVLelcddaNFVDNEYFFDRSSQAFKYIMNYYKTGHLHVMEELCAISF 82

                 ...
gi 569002937 108 LYE 110
Cdd:cd18424   83 LQE 85

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        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  32 VHIDVGGHMYTSSLATLTKYpESRIGRLFDGTEPIVLDSlKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLLYEE 111
Cdd:cd18369    1 VKLNVGGSLHYTTIGTLTKQ-DTMLRAMFSGRMEVLTDS-EGWILIDRCGKHFGTILNYLRDGSVPLPESRRELAELLAE 78

                 ....*..
gi 569002937 112 AKYFQLQ 118
Cdd:cd18369   79 AKYYLVQ 85

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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  32 VHIDVGGHMYTSSLATLTKyPESRIGRLFDGTEPIVLDSlKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLLYEE 111
Cdd:cd18400    4 VKLNVGGSLHYTTVQTLTK-QDTMLKAMFSGRVEVLTDS-EGWVLIDRSGRHFGTILNYLRDGSVPLPESTRELEELLGE 81

                         90
                 ....*....|
gi 569002937 112 AKYFQLQPML 121
Cdd:cd18400   82 ARYYLVQGLV 91

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 18 (KCTD18); KCTD18 is a BTB/POZ domain-containing protein with with unknown biological function. A duplication of the KCTD18 gene has been found in a patient with epilepsy, developmental delay, and autistic behavior, which may contribute to the phenotype. 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        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSlKQHYFIDRDGQMFRYILNFLRtSKLLIPDDFKDYTLLYEE 111
Cdd:cd18372    3 LRLNVGGCIYTARRESLCRFKDSMLSSMFSGRFPLKLDE-SGACVIDRDGRLFKYLLDYLH-GELQIPEDEQTRLALQEE 80

                 ....
gi 569002937 112 AKYF 115
Cdd:cd18372   81 ADYF 84

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 569002937  13 PLNNQGIPTPA--QLTKSNAPVHIDVGGHMYTSSLATLTKYPESRIGrlfDGTEPIVLDSLKQHYFIDRDGQMFRYILNF 90
Cdd:cd18417   16 PLAKKPMPKPPsdKKRRNDEILVVNVSGRRFQTWKNTLDRYPDTLLG---SSEKEFFYNEDTQEYFFDRDPEMFRHILNF 92

                 ....*....
gi 569002937  91 LRTSKLLIP 99
Cdd:cd18417   93 YRTGRLHYP 101

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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 569002937  34 IDVGGHMYTSSLATLTKYPESRIGrlfdGTE-PIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIP 99
Cdd:cd18380    4 INVSGRRFETWKNTLEKYPDTLLG----STEkEFFYDDDTKEYFFDRDPEIFRHILNFYRTGKLHYP 66

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

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPivLDSLKQH---YFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLL 108
Cdd:cd18362    2 VKLNVGGTYFLTTRTTLCRDPKSFLCRLCQEDPD--LPSDKDEtgaYLIDRDPTYFGPILNYLRHGKLIIDKDLAEEGVL 79

                 ....*..
gi 569002937 109 yEEAKYF 115
Cdd:cd18362   80 -EEAEFY 85

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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIV-LDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDD 101
Cdd:cd18379    1 IVINVGGVRHETYKSTLRNLPDTRLAWLTETEASAFdYDPVTGEFFFDRHPGVFAQILNYYRTGKLHCPAD 71

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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIGRLFDgtEPIVLDSLKQH---YFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLL 108
Cdd:cd18389    3 VRLNVGGTYFVSTKQTLCRDPKSFLYRLCQ--EDPDLDSDKDEtgaYLIDRDPTYFGPILNYLRHGKLIINKELAEEGVL 80

                         90       100
                 ....*....|....*....|....
gi 569002937 109 yEEAKYFQLQPMLLEMERWKQDRE 132
Cdd:cd18389   81 -EEAEFYNIASLVRLVKERIRDNE 103

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

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTepivLDSLKQH---YFIDRDGQMFRYILNFLRTSKLLIpdDFKDYTLL 108
Cdd:cd18392    4 IQLNVGGTRFSTSRQTLMWIPDSFFSSLLSGR----ISSLKDEtgaIFIDRDPTAFVPILNFLRTKELDL--RGVNINVL 77

                         90
                 ....*....|.
gi 569002937 109 YEEAKYFQLQP 119
Cdd:cd18392   78 RHEAEFYGITP 88

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 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIGRLfdgTEPIV-LDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDyTLLYE 110
Cdd:cd18416    4 VVLNVGGIRHETYKATLKKIPATRLSRL---TEALAnYDPVLNEYFFDRHPGVFAQILNYYRTGKLHYPTDVCG-PLFEE 79

                         90
                 ....*....|....*....
gi 569002937 111 EAKYFQLQPMLLEMERWKQ 129
Cdd:cd18416   80 ELEFWGLDANQVEPCCWMT 98

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

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  13 PLNNQGIP-TPAQLTKSNAPVHI-DVGGHMYTSSLATLTKYPESRIGRlfdGTEPIVLDSLKQHYFIDRDGQMFRYILNF 90
Cdd:cd18419   16 PVANCPMPlAPADKNKRQDELIVlNVSGRRFQTWRTTLERYPDTLLGS---TEKEFFFNEDTKEYFFDRDPEVFRCVLNF 92

                         90       100       110
                 ....*....|....*....|....*....|...
gi 569002937  91 LRTSKLLIPDdfKDYTLLY-EEAKYFQLQPMLL 122
Cdd:cd18419   93 YRTGKLHYPR--YECISAYdEELAFYGILPEII 123

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily D member 2 (KCND2); KCND2, also called voltage-gated potassium channel subunit Kv4.2, is a major pore-forming subunit in somatodendritic subthreshold A-type potassium current I(SA) channels. It mediates transmembrane potassium transport in excitable membranes, primarily in the brain. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCND2 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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 569002937  34 IDVGGHMYTSSLATLTKYPESRIGrlfDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIP 99
Cdd:cd18418    4 LNVSGTRFQTWRNTLERYPDTLLG---SSERDFFYHEETQEYFFDRDPDIFRHILNFYRTGKLHYP 66

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

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIGRLFD-GTEPIVLD------SLKQHYFIDRDGQMFRYILNFLRTSKL 96
Cdd:cd18428    3 INLNVGGFKQSVDQSTLLRFPHTRLGKLLNcHSEEAILElcddysVADKEYYFDRNPSLFRYVLNFYYTGKL 74

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in KCNS/Kv9 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 Kv9, also known as subfamily S, includes KCNS1 (Kv9.1), KCNS2 (Kv9.2) and KCNS3 (Kv9.3). They are regulatory alpha subunits that cannot form functional homo-tetrameric channels. Both KCNS1 and KCNS2 are delayed-rectifier K(+) channel alpha subunits 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. KCNS3 is a delayed-rectifier K(+) channel alpha subunit linked to tissue oxygenation responses. It 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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIGRLF--DGTEPIV-----LDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDD 101
Cdd:cd18384    1 IRINVGGFRRRLSASALLRFPGTRLGRLLacHSEEAILelcddYDVAAREFYFDRNPGFFLYVLHFYRTGKLHVMDE 77

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

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 569002937  34 IDVGGHMYTSSLATLTKYPESRIGRLfdgTEPIVL-----DSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFkdYTLL 108
Cdd:cd18414    7 INVGGTRHETYRSTLRTLPGTRLAWL---AEPDAHsnfdyDPRADEFFFDRHPGVFAHILNYYRTGKLHCPADV--CGPL 81

                 ....*..
gi 569002937 109 YEEAKYF 115
Cdd:cd18414   82 YEEELAF 88

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

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIGRL-----FDGTEPIV--LDSLKQHYFIDRDGQMFRYILNFLRTSKL 96
Cdd:cd18421    6 VIINVGGIKYRIPWTTLEEFPLTRLGQLkscnnFDEIMDICddYDVTCNEFFFDRNPCAFRTILTFLRAGKL 77

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily B member 2 (KCNB2); KCNB2, also called voltage-gated potassium channel subunit Kv2.2, mediates transmembrane potassium transport in excitable membranes, primarily in the brain and smooth muscle cells. 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. KCNB2 contributes to the delayed-rectifier voltage-gated potassium current in cortical pyramidal neurons and smooth muscle cells. 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. KCNB2 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 569002937  20 PTPAQLTKSNA---PVHIDVGGHMYTSSLATLTKYPESRIGRLFD-GTEPIVLD-----SLKQH-YFIDRDGQMFRYILN 89
Cdd:cd18412    4 PEPVEIIRSKAcsrRVKINVGGLNHEVLWRTLDRLPRTRLGKLRDcNTHESLLEvcddyNLNENeYFFDRHPGAFTSILN 83

                 ....*..
gi 569002937  90 FLRTSKL 96
Cdd:cd18412   84 FYRTGKL 90

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 569002937  32 VHIDVGGHMYTSSLATLTKYPESRIG------RLFDgtepivldSLKQHYFIDRDGQMFRYILNFLRTSKLL-----IPD 100
Cdd:cd18403    3 VVINISGLRFETQLKTLAQFPETLLGdpkkrmRYFD--------PLRNEYFFDRNRPSFDAILYYYQSGGRLrrpvnVPL 74

                         90       100
                 ....*....|....*....|....*.
gi 569002937 101 DfkdytLLYEEAKYFQLQPMLLEMER 126
Cdd:cd18403   75 D-----IFSEEIRFYELGEEAMEMFR 95