BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain superfamily; Proteins in this superfamily are characterized by the presence of a common protein-protein interaction motif of about 100 amino acids, known as the BTB/POZ domain. Members include transcription factors, oncogenic proteins, ion channel proteins, and potassium channel tetramerization domain (KCTD) proteins. They have been identified in poxviruses and many eukaryotes, and have diverse functions, such as transcriptional regulation, chromatin remodeling, protein degradation and cytoskeletal regulation. Many BTB/POZ proteins contain one or two additional domains, such as kelch repeats, zinc-finger domains, FYVE (Fab1, YOTB, Vac1, and EEA1) fingers, or ankyrin repeats, among others. These special additional domains or interaction partners provide unique characteristics and functions to BTB/POZ proteins. In ion channel proteins and KCTD proteins, the BTB/POZ domain is also called the tetramerization (T1) domain.

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gi 15230066    18 LKEQRQ----VDVRLKAGDsdqkgVSISAHKLVLSARSEVFKMILETEEIKATTTldTITLSELKHTELVALVE 87
Cdd:pfam00651   1 LNELREqgelCDVTLVVGD-----KEFRAHKAVLAACSPYFKALFSGQESESSVS--EITLDDVSPEDFEALLE 67

BTB/POZ domain; The BTB (for BR-C, ttk and bab) or POZ (for Pox virus and Zinc finger) domain is present near the N-terminus of a fraction of zinc finger (pfam00096) proteins and in proteins that contain the pfam01344 motif such as Kelch and a family of pox virus proteins. The BTB/POZ domain mediates homomeric dimerization and in some instances heteromeric dimerization. The structure of the dimerized PLZF BTB/POZ domain has been solved and consists of a tightly intertwined homodimer. The central scaffolding of the protein is made up of a cluster of alpha-helices flanked by short beta-sheets at both the top and bottom of the molecule. POZ domains from several zinc finger proteins have been shown to mediate transcriptional repression and to interact with components of histone deacetylase co-repressor complexes including N-CoR and SMRT. The POZ or BTB domain is also known as BR-C/Ttk or ZiN.

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gi 15230066    18 LKEQRQ----VDVRLKAGDsdqkgVSISAHKLVLSARSEVFKMILETEEIKATTTldTITLSELKHTELVALVE 87
Cdd:pfam00651   1 LNELREqgelCDVTLVVGD-----KEFRAHKAVLAACSPYFKALFSGQESESSVS--EITLDDVSPEDFEALLE 67

Broad-Complex, Tramtrack and Bric a brac; Domain in Broad-Complex, Tramtrack and Bric a brac. Also known as POZ (poxvirus and zinc finger) domain. Known to be a protein-protein interaction motif found at the N-termini of several C2H2-type transcription factors as well as Shaw-type potassium channels. Known structure reveals a tightly intertwined dimer formed via interactions between N-terminal strand and helix structures. However in a subset of BTB/POZ domains, these two secondary structures appear to be missing. Be aware SMART predicts BTB/POZ domains without the beta1- and alpha1-secondary structures.

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gi 15230066    25 DVRLKAGdsdqkGVSISAHKLVLSARSEVFKMILETEEIKATTTldTITLSELKHTELVALVE 87
Cdd:smart00225  1 DVTLVVG-----GKKFHAHKAVLAAHSPYFKALFSSDFKESDKS--EIYLDDVSPEDFRALLN 56

BTB/POZ domain; The BTB (for BR-C, ttk and bab) or POZ (for Pox virus and Zinc finger) domain is present near the N-terminus of a fraction of zinc finger (pfam00096) proteins and in proteins that contain the pfam01344 motif such as Kelch and a family of pox virus proteins. The BTB/POZ domain mediates homomeric dimerization and in some instances heteromeric dimerization. The structure of the dimerized PLZF BTB/POZ domain has been solved and consists of a tightly intertwined homodimer. The central scaffolding of the protein is made up of a cluster of alpha-helices flanked by short beta-sheets at both the top and bottom of the molecule. POZ domains from several zinc finger proteins have been shown to mediate transcriptional repression and to interact with components of histone deacetylase co-repressor complexes including N-CoR and SMRT. The POZ or BTB domain is also known as BR-C/Ttk or ZiN.

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gi 15230066    18 LKEQRQ----VDVRLKAGDsdqkgVSISAHKLVLSARSEVFKMILETEEIKATTTldTITLSELKHTELVALVE 87
Cdd:pfam00651   1 LNELREqgelCDVTLVVGD-----KEFRAHKAVLAACSPYFKALFSGQESESSVS--EITLDDVSPEDFEALLE 67

BTB (Broad-Complex, Tramtrack and Bric a brac) /POZ (poxvirus and zinc finger) domain found in Drosophila melanogaster proteins bric-a-brac 1 (BAB1), bric-a-brac 2 (BAB2), modifier of mdg4 (doom), and similar proteins; BAB1 and BAB2 probably act as transcriptional regulators that are required for specification of the tarsal segment and are involved in antenna development. Doom is a product of the Drosophila mod(mdg4) gene. It induces apoptosis and binds to baculovirus inhibitor-of-apoptosis proteins. This subfamily also includes Drosophila melanogaster sex determination protein fruitless (FRU), protein jim lovell (LOV), zinc finger protein chinmo, transcription factor GAGA, transcription factor Ken, and longitudinals lacking proteins (LOLA). FRU probably acts as a transcriptional regulator that plays a role in male courtship behavior and sexual orientation, and enhances male-specific expression of takeout in brain-associated fat body. LOV, also called tyrosine kinase-related (TKR), has a regulatory role during midline cell development. Chinmo is a functional effector of the JAK/STAT pathway that regulates eye development, tumor formation, and stem cell self-renewal in Drosophila. GAGA is a transcriptional activator that functions by regulating chromatin structure. Ken, also termed protein Ken and Barbie, is a transcription factor required for Terminalia development. LOLA proteins are putative transcription factors required for axon growth and guidance in the central and peripheral nervous systems. Proteins in this subfamily contain a BTB domain. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

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gi 15230066 24 VDVRLKAGdsdqkGVSISAHKLVLSARSEVFKMILETEEikaTTTLDTITLSELKHTELVALVE 87
Cdd:cd18315  2 VDVTLACE-----GGSLKAHKLVLAAASPYFAALLKETP---PDEHPVIILPDVPYSELKALLD 57

first BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in BTB/POZ domain-containing protein 8 (BTBD8); BTBD8 is a BTB-domain-containing Kelch-like protein that may play a role in developmental processes. It may also act as a protein-protein adaptor in a transcription complex and thus be involved in brain development. BTBD8 contains two BTB domains. This model corresponds to the first domain. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

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gi 15230066  14 LARILKEQRQVDVRLKAGdsdqkGVSISAHKLVLSARS-EVFKMILE---TEEIKATTTLDTITLSELKH 79
Cdd:cd18285   6 LLRLLREELHTDVTFYVG-----STLFKAHKAILLARVpEFFSHIIGklsSLEDQEPINIENLEASEFKT 70

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in BTB/POZ domain-containing protein 19 (BTBD19); BTBD19 is a BTB domain-containing protein. Its function remains unclear. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

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gi 15230066  25 DVRLKAGDSDQKgvsISAHKLVLSARSEVFKMILETEEIKATTTlDTITLSELK 78
Cdd:cd18294  16 DVKFLVGPERQE---IFAHKCILAARCEVFRAMFLTGPQKESTQ-SPLVLSDIE 65

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like ECH-associated protein 1 (KEAP1); KEAP1, also called cytosolic inhibitor of Nrf2 (INrf2) or Kelch-like protein 19 (KLHL19), is a redox-regulated substrate adaptor protein for a Cullin3-dependent ubiquitin ligase complex that targets NFE2L2/NRF2 for ubiquitination and degradation by the proteasome, thus resulting in the suppression of its transcriptional activity and the repression of antioxidant response element-mediated detoxifying enzyme gene expression. It contains a BTB domain and kelch repeats, characteristics of a kelch family protein. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

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gi 15230066  18 LKEQRQV-DVRLKAGDSDQKgVSISAHKLVLSARSEVFK 55
Cdd:cd18248  15 LRLSQQLcDVTLKVKYQDPK-EEFMAHKVVLASSSPYFK 52

BTB (Broad-Complex, Tramtrack and Bric a brac) /POZ (poxvirus and zinc finger) domain found in plant regulatory proteins, NPR1-4, and similar proteins; NPR1 and NPR2 are essential for pathogenicity and the utilization of many nitrogen sources. NPR1 is also called nitrogen pathogenicity regulation protein NPR1, non-inducible immunity protein 1 (Nim1), nonexpresser of PR genes 1, or salicylic acid insensitive 1 (Sai1). It acts as a transcription coactivator that plays dual roles in regulating plant immunity. NPR3 and NPR4 are involved in negative regulation of defense responses against pathogens in plant. NPR proteins contain a BTB domain, DUF3420, ankyrin (ANK) repeats, and a conserved C-terminal domain. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

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gi 15230066  37 GVSISAHKLVLSARSEVFKMILETEEIKATTTLDTITLSEL 77
Cdd:cd18310  28 GRPVPVHRCILAARSPFFRDIFASAKAEGANTKPKLELREL 68

first BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Rho-related BTB domain-containing proteins (RhoBTB); RhoBTB proteins constitute a subfamily of atypical members within the Rho family of small guanosine triphosphatases (GTPases), which is characterized by containing a GTPase domain (in most cases, non-functional) followed by a proline-rich region, tandem BTB domains, and a conserved C-terminal region. In vertebrates, the RhoBTB subfamily consists of 3 isoforms: RhoBTB1, RhoBTB2, and RhoBTB3. Orthologs are present in several other eukaryotes, such as Drosophila and Dictyostelium, but have been lost in plants and fungi. This model corresponds to the first BTB domain. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

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gi 15230066  13 GLARILKEQRQVDVRLKAGDsdqkGVSISAHKLVLSARSEVFKMILETE 61
Cdd:cd18299   2 DLRNLLHSPSCADVVFILQG----GVRIFAHRIVLAAASSVFADLFLMM 46