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 218505694 636 SNAPVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTL 715
Cdd:cd18387    1 SNAPVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYSL 80

                         90       100
                 ....*....|....*....|....*
gi 218505694 716 LYEEAKYFQLQPMLLEMERWKQDRE 740
Cdd:cd18387   81 LYEEAKYFQLQPMLLELERWKQDRE 105

H1 domain found in potassium channel tetramerization domain-containing proteins; The H1 domain is found in potassium channel tetramerization domain-containing proteins such as KCTD8, KCTD12 (also called predominantly fetal expressed T1 domain/Pfetin), KCTD12b, and KCTD16. They serve as auxiliary gamma-aminobutyric acid type B (GABA-B) receptor subunits that constitute receptor subtypes with distinct functional properties. KCTD12 and -12b generate desensitizing receptor responses while KCTD8 and -16 generate largely non-desensitizing receptor responses. They control GABA-B signaling and regulate the rise time and duration of G protein-coupled inwardly rectifying potassium (GIRK) currents, as well as enhance receptor expression levels. KCTD12 regulates agonist potency and kinetics of GABA-B 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. Members of this family consist of an N-terminal BTB domain followed by a region called the H1 domain. The BTB domain mediates interaction with the receptor. The C-terminal H1 domain, which possesses a beta-propeller-like fold, engages in interactions with G-protein beta-gamma subunits and is responsible for desensitization. This model corresponds to the H1 domain.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 218505694 762 RITLSGDKSLIEEVFpeiGDVMCNSVNAGWNHDSTHVIRFPLNgYCHLNsvQVLERLQQRGFEIVGSCGGGVDS------ 835
Cdd:cd22204   29 RILVCGKVSLCREVF---GDTLNESRDPDRGEPDRYTSRFFLK-HNYLE--QAFDQLAEAGFRLVASCGSGTSGlpsagd 102

                         90
                 ....*....|....*.
gi 218505694 836 ------SQFSEYVLRR 845
Cdd:cd22204  103 seekrwNHYTEFVFVR 118

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 218505694 636 SNAPVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTL 715
Cdd:cd18387    1 SNAPVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYSL 80

                         90       100
                 ....*....|....*....|....*
gi 218505694 716 LYEEAKYFQLQPMLLEMERWKQDRE 740
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 218505694   640 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPivlDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDfkDYTLLYEE 719
Cdd:smart00225   2 VTLVVGGKKFHAHKAVLAAHSPYFKALFSSDFKE---SDKSEIYLDDVSPEDFRALLNFLYTGKLDLPEE--NVEELLEL 76

                           90
                   ....*....|....*.
gi 218505694   720 AKYFQLQPMLLEMERW 735
Cdd:smart00225  77 ADYLQIPGLVELCEEF 92

H1 domain found in potassium channel tetramerization domain-containing proteins; The H1 domain is found in potassium channel tetramerization domain-containing proteins such as KCTD8, KCTD12 (also called predominantly fetal expressed T1 domain/Pfetin), KCTD12b, and KCTD16. They serve as auxiliary gamma-aminobutyric acid type B (GABA-B) receptor subunits that constitute receptor subtypes with distinct functional properties. KCTD12 and -12b generate desensitizing receptor responses while KCTD8 and -16 generate largely non-desensitizing receptor responses. They control GABA-B signaling and regulate the rise time and duration of G protein-coupled inwardly rectifying potassium (GIRK) currents, as well as enhance receptor expression levels. KCTD12 regulates agonist potency and kinetics of GABA-B 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. Members of this family consist of an N-terminal BTB domain followed by a region called the H1 domain. The BTB domain mediates interaction with the receptor. The C-terminal H1 domain, which possesses a beta-propeller-like fold, engages in interactions with G-protein beta-gamma subunits and is responsible for desensitization. This model corresponds to the H1 domain.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 218505694 762 RITLSGDKSLIEEVFpeiGDVMCNSVNAGWNHDSTHVIRFPLNgYCHLNsvQVLERLQQRGFEIVGSCGGGVDS------ 835
Cdd:cd22204   29 RILVCGKVSLCREVF---GDTLNESRDPDRGEPDRYTSRFFLK-HNYLE--QAFDQLAEAGFRLVASCGSGTSGlpsagd 102

                         90
                 ....*....|....*.
gi 218505694 836 ------SQFSEYVLRR 845
Cdd:cd22204  103 seekrwNHYTEFVFVR 118

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 218505694 636 SNAPVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTL 715
Cdd:cd18387    1 SNAPVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYSL 80

                         90       100
                 ....*....|....*....|....*
gi 218505694 716 LYEEAKYFQLQPMLLEMERWKQDRE 740
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 218505694 637 NAPVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLL 716
Cdd:cd18388    1 NAPVHIDVGGHMYTSSLATLTKYPDSRISRLFNGTEPIVLDSLKQHYFIDRDGEIFRYILSFLRTSKLLLPEDFKDFNLL 80

                         90
                 ....*....|....*....
gi 218505694 717 YEEAKYFQLQPMLLEMERW 735
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 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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 218505694 639 PVHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSlKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLLYE 718
Cdd:cd18394    4 PVTLNVGGHLYTTSLSTLTRYPDSMLGAMFRGDFPTARDS-QGNYFIDRDGPLFRYILNFLRTSELTLPVDFKEFDLLRK 82

                         90
                 ....*....|.
gi 218505694 719 EAKYFQLQPML 729
Cdd:cd18394   83 EADFYQIEPLI 93

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 218505694 640 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSlKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLLYEE 719
Cdd:cd18316    1 VKLNVGGTLFTTSRSTLLKDPDSLLAALFSGRWPLPRDE-DGSIFIDRDPELFRHILNFLRTGKLPLPSDFVELEELLAE 79

                 ....
gi 218505694 720 AKYF 723
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 218505694 640 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEP--IVLDSlKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLLY 717
Cdd:cd18367    5 VELNVGGQVYTTSLSTLIKDPDSLLGRMFSGKNRqeLARDS-KGRYFLDRDGVLFRYILDYLRNQKLVLPENFPERERLK 83

                         90
                 ....*....|..
gi 218505694 718 EEAKYFQLQPML 729
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 218505694 640 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPiVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLLYEE 719
Cdd:cd18375    3 VTLNVGGKKFTTRPSTLRRFPDSRLARMLDGKDQ-DFKVVNGQFFVDRDGSLFSYILDYLRTGQLTLPTEFSDYNRLARE 81

                         90
                 ....*....|....*
gi 218505694 720 AKYFQLQPMLLEMER 734
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 218505694 640 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSlKQHYFIDRDGQMFRYILNFLRTSKL---LIPDdfkdytlL 716
Cdd:cd18371    4 VSLNVGGHIYTTTLSTLRKFPGSKLAELFNGQPKLRTDS-EGRYFIDRDGTYFRYILEYLRTNQVptqHIQE-------V 75

                         90
                 ....*....|....*..
gi 218505694 717 YEEAKYFQLQPMLLEME 733
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 218505694 640 VHIDVGGHMYTSSLATLTKYPESRIGRLF----DGTEPIVLDSlKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTL 715
Cdd:cd18398    5 VELNVGGQVYFTRHATLVSIPHSLLWKMFspkrDTANDLAKDS-KGRFFIDRDGFLFRYILDYLRDRQVVLPDHFPEKGR 83

                         90
                 ....*....|....*..
gi 218505694 716 LYEEAKYFQLqPMLLEM 732
Cdd:cd18398   84 LKREAEYFQL-PDLVKL 99

second 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 second 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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 218505694 640 VHIDVGGHMYTSSLATLTKYPEsrigrLFDGTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLLYEE 719
Cdd:cd18374    3 VKVYVGSHWYATYLKTLLKYPE-----LLSNSKKVRWITYGQTLLISGDGQMFRHILNFLRLGKLLLPSEFKEWPLLCQE 77

                         90
                 ....*....|..
gi 218505694 720 AKYFQLqPMLLE 731
Cdd:cd18374   78 VEEYQI-PALSE 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        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 218505694  640 VHIDVGGHMYTSSLATLTKYPESRIGRLFDgTEPIVLDSLKQHYFIDRDGQMFRYILNFLRTS-KLLIPDDfKDYTLLYE 718
Cdd:pfam02214   1 VKLNVGGTRFETLKSTLTRFPDTRLGRLLE-LECDDYDDDTNEYFFDRSPKHFETILNFYRTGgKLHRPEE-VCLDEFLE 78

                          90
                  ....*....|....
gi 218505694  719 EAKYFQLQPMLLEM 732
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 218505694 640 VHIDVGGHMYTSSLATLTKY-PESRIGRLF--DGTEPIVLDSlKQHYFIDRDGQMFRYILNFLRTSKLLIpDDFKDYTLL 716
Cdd:cd18368    3 IKLNVGGRIFTTTRSTLVKKePDSMLARMFsdDSTWPSSRDE-NGAYLIDRSPEYFEPILNYLRHGQLIL-NDGLNPLGV 80

                         90
                 ....*....|....*..
gi 218505694 717 YEEAKYFQLQPMLLEME 733
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 218505694 642 IDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVL------DSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTL 715
Cdd:cd18424    3 INVGGSRFVLSQQVLSSHPETRLGKLAVSVRDSVLelcddaNFVDNEYFFDRSSQAFKYIMNYYKTGHLHVMEELCAISF 82

                 ...
gi 218505694 716 LYE 718
Cdd:cd18424   83 LQE 85

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 218505694   640 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPivlDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDfkDYTLLYEE 719
Cdd:smart00225   2 VTLVVGGKKFHAHKAVLAAHSPYFKALFSSDFKE---SDKSEIYLDDVSPEDFRALLNFLYTGKLDLPEE--NVEELLEL 76

                           90
                   ....*....|....*.
gi 218505694   720 AKYFQLQPMLLEMERW 735
Cdd:smart00225  77 ADYLQIPGLVELCEEF 92

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        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 218505694 640 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIVLDSLKQhYFIDRDGQMFRYILNFLRTSKLLIPDdfKDYTLLYEE 719
Cdd:cd18393    4 IHLNVGGKRFSTSRQTLTWIPDSFFSSLLSGRISTLKDETGA-IFIDRDPTVFAPILNFLRTKELDPRG--IHVSLLLHE 80

                         90
                 ....*....|....
gi 218505694 720 AKYFQLQPMLLEME 733
Cdd:cd18393   81 AQFYGITPLVRRLQ 94

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 218505694 640 VHIDVGGHMYTSSLATLTKyPESRIGRLFDGTEPIVLDSlKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLLYEE 719
Cdd:cd18400    4 VKLNVGGSLHYTTVQTLTK-QDTMLKAMFSGRVEVLTDS-EGWVLIDRSGRHFGTILNYLRDGSVPLPESTRELEELLGE 81

                         90
                 ....*....|
gi 218505694 720 AKYFQLQPML 729
Cdd:cd18400   82 ARYYLVQGLV 91

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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 218505694 641 HIDVGGHMYTSSLATLTKYPESRIGRlfdgtEPIVLD-SLKQHYFIDRDGQMFRYILNFLRTSKLLIpDDFKDYTLLYEE 719
Cdd:cd18373    2 YFNVGGWIFSVPKSKLAQFPDSLLWK-----EASSLSeSENTRLFIDRDGFTFRHVHYYLQTSKLSS-SSCSELNLLYEQ 75

                         90       100
                 ....*....|....*....|.
gi 218505694 720 AKYFQLQPMLLEMERWKQDRE 740
Cdd:cd18373   76 AAGLQLTSLLQALDNLKEGKH 96

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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 218505694 634 TKSNAPVHIDVGGHMYTSSLATLTKyPESRIGRLFDGTEPIVLDSlKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDY 713
Cdd:cd18399    3 SPSSKYVKLNVGGALYYTTMQTLTK-QDTMLKAMFSGRMEVLTDS-EGWILIDRCGKHFGTILNYLRDGAVPLPESRREI 80

                         90       100
                 ....*....|....*....|....*...
gi 218505694 714 TLLYEEAKYFQLQPMLLEMERWKQDRET 741
Cdd:cd18399   81 EELLAEAKYYLVQGLVEECQAALQNKDT 108

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium voltage-gated channel subfamily S member 1 (KCNS1); KCNS1, also called delayed-rectifier K(+) channel alpha subunit 1 or voltage-gated potassium channel subunit Kv9.1, is a modulatory alpha subunit of voltage-gated potassium channel that mediates neuropathic pain following nerve injury. It can form functional heterotetrameric channels with KCNB1 (also known as Kv2.1) and KCNB2 (also known as Kv2.2), and further modulates the delayed rectifier voltage-gated potassium channel activation and deactivation rates of KCNB1 and KCNB2. Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. KCNS1 is a regulatory alpha subunit that cannot form a functional homo-tetrameric channel. It forms hetero-tetrameric channels (with other functional alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 218505694 640 VHIDVGGHMYTSSLATLTKYPESRIGRLF--DGTEPIV-----LDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKD 712
Cdd:cd18426    1 ININVGGLKRRLSSSTLSKFPDTRLGRLLscDSEESILqicddYDVSAKEFYFDRNPGLFPYVLHFYQTGKLHIMEELCV 80

                         90
                 ....*....|....*....
gi 218505694 713 YTlLYEEAKYFQLQPMLLE 731
Cdd:cd18426   81 FS-FSQEIEYWGINEFFLD 98

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 218505694 640 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEPIV-LDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDD 709
Cdd:cd18379    1 IVINVGGVRHETYKSTLRNLPDTRLAWLTETEASAFdYDPVTGEFFFDRHPGVFAQILNYYRTGKLHCPAD 71

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        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 218505694 637 NAPVHIDVGGHMYTSSLATLTKYpESRIGRLFDGTEPIVLDslKQHY-FIDRDGQMFRYILNFLRTSKLLIPDDFKDYTL 715
Cdd:cd18401    2 NKYVRLNVGGSLYYTTVQVLTRH-DTMLKAMFSGRMEVLTD--KEGWiLIDRCGKHFGTILNYLRDDTVALPKSRQEIKE 78

                         90       100
                 ....*....|....*....|....*
gi 218505694 716 LYEEAKYFQLQPMLLEMERWKQDRE 740
Cdd:cd18401   79 LMAEAKYYLIQGLVDMCQAALQDKK 103

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.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 218505694 640 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGT--EPIV-----LDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDD 709
Cdd:cd18378    4 VLLNVGGVRHEVLWRTLDRLPRTRLGRLRECNthESLLelcddYDLEDNEYFFDRHPGAFTSILNFYRTGKLHMPEE 80

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Drosophila melanogaster potassium voltage-gated channel protein Shal and similar proteins; Drosophila melanogaster Shal, also called Shaker cognate l or Shal2, is a transient potassium current (I(A)) channel, which is required for maintaining excitability during repetitive firing and normal locomotion in Drosophila. It may play a role in the nervous system and in the regulation of beating frequency in pacemaker cells. Shal mediates the voltage-dependent potassium ion permeability of excitable membranes. Assuming opened or closed conformations in response to the voltage difference across the membrane, the protein forms a 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. Shal 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 218505694 621 PLNNQGIPTPAQLTKSNAP----VHIDVGGHMYTSSLATLTKYPESRIGrlfDGTEPIVLDSLKQHYFIDRDGQMFRYIL 696
Cdd:cd18420   15 PIANNPLPPPPVDQERRRTddekLIINVSGRRFETWRNTLEKYPDTLLG---SNEREFFYDEETKEYFFDRDPDIFRHIL 91

                         90       100       110
                 ....*....|....*....|....*....|.
gi 218505694 697 NFLRTSKLLIPDDfKDYTLLYEEAKYFQLQP 727
Cdd:cd18420   92 NYYRTGKLHYPKH-ECLTAYDEELAFFGIMP 121

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 218505694 621 PLNNQGIP-TPAQLTKSNAPVHI-DVGGHMYTSSLATLTKYPESRIGRlfdGTEPIVLDSLKQHYFIDRDGQMFRYILNF 698
Cdd:cd18419   16 PVANCPMPlAPADKNKRQDELIVlNVSGRRFQTWRTTLERYPDTLLGS---TEKEFFFNEDTKEYFFDRDPEVFRCVLNF 92

                         90       100       110
                 ....*....|....*....|....*....|...
gi 218505694 699 LRTSKLLIPDdfKDYTLLY-EEAKYFQLQPMLL 730
Cdd:cd18419   93 YRTGKLHYPR--YECISAYdEELAFYGILPEII 123

Domain of unknown function (DUF3504); This presumed domain is functionally uncharacterized. This domain is found in eukaryotes. This domain is typically between 156 to 173 amino acids in length.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 218505694  284 ITRADLRKLYTSSVFSTNTPFGLLNKVWFETCMYFCTRGRENQRELEEDSFGLAMDEDGR-KFVYFKslgpYHKSRSSSW 362
Cdd:pfam12012   2 FSRVEEEHLWECKQLGAHSPIVLLNTLVYFNTKYFNLRTVEEHRRLSFSNVVRHTKPNPReKSTYLR----YYEPPDQVE 77

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 218505694  363 SKKRAESSDEENL-PRMYE--TGTEFCPYASFVKYLSKRNPLCK----AFFQRPRDHCSEGDVTWYENKAIGKNLLGtrm 435
Cdd:pfam12012  78 TGGRKKRDEGVNKvVEQHEnsENPLRCPVKLYEFYLSKCPESVKqrkdVFYLQPEPSCVPDSPLWYSSQPLGRNTLE--- 154

                  ....*
gi 218505694  436 QMLSK 440
Cdd:pfam12012 155 SMLTR 159

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in KCNG/Kv6 subfamily of potassium voltage-gated channels; Voltage-gated potassium (Kv) channels are composed of alpha subunits, which form the actual conductance pore, and cytoplasmic beta subunits, which are auxiliary proteins that associate with alpha subunits to modulate the activity of the Kv channel. The potassium voltage-gated channel subfamily Kv6, also known as subfamily G, includes KCNG1 (Kv6.1), KCNG2 (Kv6.2 or KCNF2), KCNG3 (Kv6.3) and KCNG4 (Kv6.4), which are regulatory alpha subunits and do not form functional channels on their own. KCNG1 can form functional heterotetrameric channels with KCNB1 (also known as Kv2.1), and further modulates the delayed rectifier voltage-gated potassium channel activation and deactivation rates of KCNB1. KCNG2, also called cardiac potassium channel subunit, can form functional heterodimeric channels with KCNB1, and further modulates channel activity by shifting the threshold and the half-maximal activation to more negative values. KCNG3, also called voltage-gated potassium channel subunit Kv10.1, is an electrically silent modulatory subunit that can form functional heterotetrameric channels with KCNB1, and further promotes a reduction in the rate of activation and inactivation of the delayed rectifier voltage-gated potassium channel KCNB1. KCNG4 is a silent voltage-gated potassium (KvS) channel subunit that can form functional heterotetrameric channels with KCNB1, and further modulates the delayed rectifier voltage-gated potassium channel activation and deactivation rates of KCNB1.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 218505694 642 IDVGGHMYTSSLATLTKYPESRIGRL--FDGTEPIV-----LDSLKQHYFIDRDGQMFRYILNFLRTSKL 704
Cdd:cd18382    3 INVGGARYSLPWSTLDRFPLTRLSRLkaCRSEDDILrvcddYDVERNEFFFDRSPEAFGVILLFLRAGKL 72

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 218505694 640 VHIDVGGHMYTSSLATLTKYPESRIGRLF--DGTEPIV-----LDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDD 709
Cdd:cd18384    1 IRINVGGFRRRLSASALLRFPGTRLGRLLacHSEEAILelcddYDVAAREFYFDRNPGFFLYVLHFYRTGKLHVMDE 77

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Drosophila melanogaster potassium voltage-gated channel protein Shab and similar proteins; Shab is a slow delayed rectifier 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. Shab 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 218505694 637 NAPVHIDVGGHMYTSSLATLTKYPESRIGRLFDGT--EPIV-----LDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDD 709
Cdd:cd18413    1 NRRVVINVGGVKHEVLWRTLDRMPHTRLGKLRDSNthEAIVelcddYSLADNEYFFDRHPRSFASILNFYRTGKLHLVEE 80

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 218505694 640 VHIDVGGHMYTSSLATLTKYPESRIGRL-----FDGTEPIV--LDSLKQHYFIDRDGQMFRYILNFLRTSKL 704
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 A member 4 (KCNA4); KCNA4 is also called HPCN2, or voltage-gated K(+) channel HuKII, voltage-gated potassium channel HBK4, voltage-gated potassium channel HK1, or voltage-gated potassium channel subunit Kv1.4. 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. KCNA4 is an alpha subunit that forms functional homo- or hetero-tetrameric channels (with other Kv1/KCNA alpha subunits) through its BTB/POZ domain, also known as tetramerization (T1) domain, which is a versatile protein-protein interaction motif.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 218505694 640 VHIDVGGHMYTSSLATLTKYPESRIGRLFDGTEpiVLDSLKQHYFIDRDGQMFRYILNFLRTSKLLIPDDFKDYTLLYEE 719
Cdd:cd18405    3 VVINVSGLRFETQLKTLAQFPETLLGDPEKRMR--YFDPLRNEYFFDRNRPSFDAILYYYQSGGRLKRPVNVPFDIFSEE 80