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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888  43 QLSQDLLRLLREEFHTDVTFSVGYTLFKAHKAVLLARVPDFYFHTIGQTSnSLTNQEPIAVENVEALEFRTFLQIIYSSN 122
Cdd:cd18285    1 HLSQDLLRLLREELHTDVTFYVGSTLFKAHKAILLARVPEFFSHIIGKLS-SLEDQEPINIENLEASEFKTFLRQVYTSD 79

                         90       100
                 ....*....|....*....|....*
gi 332221888 123 RNIKNYEEEILRKKIMEIGISQKQL 147
Cdd:cd18285   80 KNIKMLEEEILKGKVLDQKVDKEND 104

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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888  43 QLSQDLLRLLREEFHTDVTFSVGYTLFKAHKAVLLARVPDFYFHTIGQTSnSLTNQEPIAVENVEALEFRTFLQIIYSSN 122
Cdd:cd18285    1 HLSQDLLRLLREELHTDVTFYVGSTLFKAHKAILLARVPEFFSHIIGKLS-SLEDQEPINIENLEASEFKTFLRQVYTSD 79

                         90       100
                 ....*....|....*....|....*
gi 332221888 123 RNIKNYEEEILRKKIMEIGISQKQL 147
Cdd:cd18285   80 KNIKMLEEEILKGKVLDQKVDKEND 104

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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888  207 DIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTldIPDKTNVGQILNMADM 286
Cdd:pfam00651  12 DVTLVVGDKEFRAHKAVLAACSPYFKALFSGQESESSVSEITLDDVSPEDFEALLEFMYTGK--LISEENVDDLLAAADK 89

                          90
                  ....*....|....
gi 332221888  287 YGLEGLKEVAIYIL 300
Cdd:pfam00651  90 LQIPSLVDKCEEFL 103

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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 332221888   48 LLRLLREEFHTDVTFSVGYTLFKAHKAVLLARVPdfYFHTI--GQTSNSltNQEPIAVENVEALEFRTFLQIIYSS 121
Cdd:pfam00651   1 LNELREQGELCDVTLVVGDKEFRAHKAVLAACSP--YFKALfsGQESES--SVSEITLDDVSPEDFEALLEFMYTG 72

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
                   ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 332221888    59 DVTFSVGYTLFKAHKAVlLARVPDfYFHTIGQTSNSLTNQEPIAVENVEALEFRTFLQIIYS 120
Cdd:smart00225   1 DVTLVVGGKKFHAHKAV-LAAHSP-YFKALFSSDFKESDKSEIYLDDVSPEDFRALLNFLYT 60

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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888  43 QLSQDLLRLLREEFHTDVTFSVGYTLFKAHKAVLLARVPDFYFHTIGQTSnSLTNQEPIAVENVEALEFRTFLQIIYSSN 122
Cdd:cd18285    1 HLSQDLLRLLREELHTDVTFYVGSTLFKAHKAILLARVPEFFSHIIGKLS-SLEDQEPINIENLEASEFKTFLRQVYTSD 79

                         90       100
                 ....*....|....*....|....*
gi 332221888 123 RNIKNYEEEILRKKIMEIGISQKQL 147
Cdd:cd18285   80 KNIKMLEEEILKGKVLDQKVDKEND 104

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in zinc finger and BTB domain-containing (ZBTB) proteins, Kelch-like (KLHL) proteins, and similar proteins; This family includes a variety of BTB/POZ domain-containing proteins, such as zinc finger and BTB domain-containing (ZBTB) proteins and Kelch-like (KLHL) proteins. They 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. These special additional domains or interaction partners provide unique characteristics and functions to BTB/POZ proteins. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 207 DIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTLDIpDKTNVGQILNMADM 286
Cdd:cd18186    3 DVTLVVGGREFPAHRAVLAARSPYFRAMFSSGMKESSSSEIELDDVSPEAFEALLDYIYTGELEL-SEENVEELLAAADK 81

                 .
gi 332221888 287 Y 287
Cdd:cd18186   82 L 82

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 332221888   207 DIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTLDIPDKtNVGQILNMADM 286
Cdd:smart00225   1 DVTLVVGGKKFHAHKAVLAAHSPYFKALFSSDFKESDKSEIYLDDVSPEDFRALLNFLYTGKLDLPEE-NVEELLELADY 79

                           90
                   ....*....|....*..
gi 332221888   287 YGLEGLKEVAIYILRRD 303
Cdd:smart00225  80 LQIPGLVELCEEFLLKL 96

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 35 (KLHL35); KLHL35 contains a BTB domain and kelch repeats, characteristics of a kelch family protein. Its function remains unclear. Significant differences in DNA methylation of the KLHL35 gene in abdominal aortic aneurysm (AAA) patients compared to non-AAA controls suggest a potential role in AAA pathology. Hypermethylation of the KLHL35 gene has also been associated with the development of hepatocellular carcinoma. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 207 DIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTLDIpDKTNVGQILNMADM 286
Cdd:cd18265   25 DVVLLVDGKDFPCHRATLSANSAYFRAMFGGHLKESRQAVVEIQKVSAAAMEVLLDYMYGGGLRI-QEDNVESVLEASDL 103

                         90       100
                 ....*....|....*....|..
gi 332221888 287 YGLEGLKEVAIYIL--RRDYCN 306
Cdd:cd18265  104 LQVSKLREACVRFLegQLHPCN 125

BTB (Broad-Complex, Tramtrack and Bric a brac) /POZ (poxvirus and zinc finger) domain found in plant ARM repeat protein interacting with ABF2 (ARIA) and similar proteins; ARIA is an armadillo (ARM) repeat and BTB domain-containing protein that acts as a positive regulator of ABA response via the modulation of the transcriptional activity of ABF2, a transcription factor which controls ABA-dependent gene expression via the G-box-type ABA-responsive elements. ARIA is a novel abscisic acid signaling component. It negatively regulates seed germination and young seedling growth. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 192 LGEDllklYVK-PCCPDIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTLD 270
Cdd:cd18352    3 LGEQ----YVNnATLSDVTFLVEGRRFYAHRIALLASSDAFRAMFDGGYREKEARDIEIPNIRWEVFELMMRFIYTGSVD 78

                         90       100       110
                 ....*....|....*....|....*....|....*
gi 332221888 271 IPdKTNVGQILNMADMYGLEGLKEVAIYILRRDYC 305
Cdd:cd18352   79 IT-NDIAKDLLRAADQYLLEGLKRLCEYTIAQDLT 112

second BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Ankyrin repeat and BTB/POZ domain-containing protein 1 (ABTB1); ABTB1, also called elongation factor 1A-binding protein or bood POZ containing gene type 1 (BPOZ-1), is an anti-proliferative factor that may act as a mediator of the phosphatase and tensin homolog (PTEN) growth-suppressive signaling pathway. It may play a role in developmental processes. ABTB1 contains an ankyrin repeat and two BTB domains. This model corresponds to the second BTB domain. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 205 CPDIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQE-----CVNLQGISHVELNVMMHFIYGGTLDIPDKtNVGQ 279
Cdd:cd18296   17 FPDVCFQVEGHRFPCHKAFFCGRSDYFKALLRDHFAESEENngsipVVTLHDVSPEVFAIVLYYIYTDDTDLPPE-NAYD 95

                         90
                 ....*....|....
gi 332221888 280 ILNMADMYGLEGLK 293
Cdd:cd18296   96 VLYVADMYLLPGLK 109

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in TD and POZ domain-containing proteins (TDPOZ); TDPOZ is a family of bipartite animal and plant proteins that contains a tumor necrosis factor receptor-associated factor (TRAF) domain (TD) and a POZ/BTB domain. TDPOZ proteins may be nuclear scaffold proteins probably involved in transcription regulation in early development and other cellular processes. This subfamily contains only mammalian members. Plant TDPOZ proteins contain a MATH domain at the N-terminal region and are named "BTB/POZ and MATH domain-containing proteins (BPM)", not included in this subfamily. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 187 EPASELGEDLLKLYVKPCCPDIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYG 266
Cdd:cd18344    5 DPRHMLTDDLGELWENSLFTDCCLLVAGHEFRAHKAILAARSPVFRAMFEHEMEERLKNPIEIHDLDPQVFKEMMGFIYT 84

                         90       100
                 ....*....|....*....|....*...
gi 332221888 267 GTL-DIPDKTNVGQILNMADMYGLEGLK 293
Cdd:cd18344   85 GKApHLHSHSMACDVLAAADKYGLEGLK 112

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Drosophila melanogaster protein roadkill and similar proteins; Drosophila melanogaster protein roadkill, also called Hh-induced MATH and BTB domain-containing protein (HIB), is a hedgehog-induced BTB protein that modulates hedgehog signaling by degrading Ci/Gli transcription factor. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 188 PASELGEDLLKLYVKPCCPDIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGG 267
Cdd:cd18345    1 PECRLSDDLGLLFERSAFSDVTLCVGGREFQAHKAILAARSPVFNAMFEHEMEERKQNRVEITDVDHEVMREMLRFIYTG 80

                         90       100
                 ....*....|....*....|....*.
gi 332221888 268 TLDIPDKTnVGQILNMADMYGLEGLK 293
Cdd:cd18345   81 KAPNLDKM-ADDLLAAADKYALERLK 105

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in plant BTB/POZ-MATH (BPM) protein family; The BPM protein family includes Arabidopsis thaliana BTB/POZ and MATH domain-containing proteins, AtBPM1-6, and similar proteins from other plants. BPM protein, also called protein BTB-POZ and MATH domain, may act as a substrate-specific adaptor of an E3 ubiquitin-protein ligase complex (CUL3-RBX1-BTB) which mediates the ubiquitination and subsequent proteasomal degradation of target proteins. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 192 LGEDLLKLYVKPCCPDIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTLdi 271
Cdd:cd18280    1 LGQHFGALLESEEGADVTFNVDGEKFRAHKLVLAARSPVFRSMLFGPMREENEGEIVIEDVEPPVFKALLHFIYKDEL-- 78

                         90       100       110
                 ....*....|....*....|....*....|....*
gi 332221888 272 PD------------KTNVGQ-ILNMADMYGLEGLK 293
Cdd:cd18280   79 PDdvepagsdssslDTTMAQhLLAAADRYALERLR 113

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 7 (KLHL7); KLHL7 is a component of a Cul3-based E3 ubiquitin ligase complex and is involved in the ubiquitination of target proteins for proteasome-mediated degradation. Mutations in KLHL7 causes autosomal-dominant retinitis pigmentosa. 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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 207 DIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTLDIPDkTNVGQILNMADM 286
Cdd:cd18237   23 DVILIVEGREIKAHRVVLAAASHFFHLMFTSNMTESKSSEVELKDAEPDIIELLVEFAYTARISVNS-NNVQSLLDAANQ 101

                         90
                 ....*....|....*
gi 332221888 287 YGLEGLKEVAIYILR 301
Cdd:cd18237  102 YQIEPVKKMCVDFLK 116

second BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 33 (KLHL33); KLHL33 contains BTB domains and kelch repeats, characteristics of a kelch family protein. Its function remains unclear. KLHL33 gene expression in normal and tumor tissue suggest a significant association with prostate cancer risk. KLHL33 contains two BTB domains. This model corresponds to the second BTB domain. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 332221888 199 LYVKPCCPDIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTL 269
Cdd:cd18263    7 LWEKGVGCDVQLEADGSIFRVHRVILAAGSDYFRAMFTSGMKESTQSVVQLPTIPAKDLRLLISFAYSGIL 77

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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 192 LGEDLLKLYVKPCCPDIDIFV--DGKRFKAHRAILSARSSYFAAMLS-GCWAESSQECVNLQGISHVELNVMMHFIYGGT 268
Cdd:cd18294    1 FAADMKSLINNPEFSDVKFLVgpERQEIFAHKCILAARCEVFRAMFLtGPQKESTQSPLVLSDIEPEVFRAVLEFIYTNC 80

                         90       100
                 ....*....|....*....|....*..
gi 332221888 269 LDIPDKTnVGQILNMADMYGLEGLKEV 295
Cdd:cd18294   81 VTLSNHT-VIEVLAAAVEYGLDELRKL 106

first BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Ankyrin repeat and BTB/POZ domain-containing protein 1 (ABTB1); ABTB1, also called elongation factor 1A-binding protein or bood POZ containing gene type 1 (BPOZ-1), is an anti-proliferative factor that may act as a mediator of the phosphatase and tensin homolog (PTEN) growth-suppressive signaling pathway. It may play a role in developmental processes. ABTB1 contains an ankyrin repeat and two BTB domains. This model corresponds to the first BTB domain. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 194 EDLLKLYVKPCCPDIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWaeSSQECVNLQG--ISHVELNVMMHFIYGGTLDI 271
Cdd:cd18295    8 EFLRRLLEQGSYSDVTFNVHGESFPAHRCILSARSPYFAEMFETKW--KDKREINLKHplVNPDAFRALLQYLYTGRLEI 85

                         90       100
                 ....*....|....*....|....
gi 332221888 272 P-DktNVGQILNMADMYGLEGLKE 294
Cdd:cd18295   86 HvD--DVEDCKRLAKQCRLEELIE 107

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 18 (KLHL18); KLHL18 acts as a substrate-specific adaptor for a Cullin3 E3 ubiquitin-protein ligase complex that regulates mitotic entry and ubiquitylates Aurora-A. 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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 207 DIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTLDIpDKTNVGQILNMADM 286
Cdd:cd18247   21 DVTLKVGDQKFSAHRIVLAATIPYFHAMFTHDMVESKQDEITMQGIEPSALEALINFAYSGRIAI-DTSNVQSLLVGASF 99

                 ....*...
gi 332221888 287 YGLEGLKE 294
Cdd:cd18247  100 LQLQSVKD 107

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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 208 IDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTLDIPDKtNVGQILNMADMY 287
Cdd:cd01165    1 VVLVVEGEKFHVNKELLAQSSEYFRALFRGGFRESGQAEINLRDISPEDFRALLEFLYGGKRDLDAS-NLLELLEAANFL 79

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like proteins, KLHL2 and KLHL3; The family includes Kelch-like proteins, KLHL2 and KLHL3. KLHL2 is a novel actin-binding protein predominantly expressed in brain. It plays a role in the reorganization of the actin cytoskeleton, and promotes growth of cell projections in oligodendrocyte precursors. KLHL2 and KLHL3 each functions as a component of an E3 ubiquitin ligase complex that mediates the ubiquitination of target proteins. They contain a BTB domain and kelch repeat domains, characteristics of a kelch family protein. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 207 DIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTLDIPDKtNVGQILNMADM 286
Cdd:cd18235   23 DVILVADGVEIPAHRVVLASCSPYFHAMFTGDLSESRANRVTLQDVDGKALLLLIDYVYTAEIQVTEE-NVQVLLPAANL 101

                         90       100
                 ....*....|....*....|....
gi 332221888 287 YGLEGLKEVAiyilrrdyCNFFQK 310
Cdd:cd18235  102 LQLTDVRDAC--------CDFLQS 117

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 10 (KLHL10); KLHL10 is a substrate-specific adaptor of a CUL3-based E3 ubiquitin-protein ligase complex which mediates the ubiquitination and subsequent proteasomal degradation of target proteins specifically in the testis during spermatogenesis. Haploinsufficiency of Klhl10 causes infertility in male mice. KLHL10 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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 207 DIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTLDIpDKTNVGQILNMADM 286
Cdd:cd18240   19 DVVIRVNGVEFPAHRNILCACSPYFRALFTNGWNETEKKVYKIPGVSPEMMELIIEYAYTRTVPI-TAENVEELLPAADQ 97

                 ....*...
gi 332221888 287 YGLEGLKE 294
Cdd:cd18240   98 FNIMGIVK 105

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in RCC1 and BTB domain-containing protein 1 (RCBTB1); RCBTB1 is also called chronic lymphocytic leukemia deletion region gene 7 protein (CLLD7), CLL deletion region gene 7 protein, regulator of chromosome condensation and BTB domain-containing protein 1, or E4.5. It is a novel chromosome condensation regulator-like guanine nucleotide exchange factor that may be involved in cell cycle regulation by chromatin remodeling. It may also function as a tumor suppressor that regulates pathways of DNA damage/repair and apoptosis. RCBTB1 may also be a substrate adaptor for a cullin3 (CUL3) E3 ligase complex that mediates the ubiquitination and subsequent proteasomal degradation of target proteins. Biallelic mutations in RCBTB1 may cause isolated and syndromic retinal dystrophy. It contains an RCC1 repeat, a BTB domain, and a BACK domain. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 192 LGEDLLKLYVKPCCPDIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTLDI 271
Cdd:cd18353    7 VAESLKKEFDSPETSDLKFRVDGKYIHVHKAVLKIRCEHFRTMFQSHWNEDMKEVIEIDQFSYPVYRAFLEYLYTDSVDL 86

                         90       100       110
                 ....*....|....*....|....*....|.
gi 332221888 272 PDKTNVGqILNMADMYGLEGLKEVAIYILRR 302
Cdd:cd18353   87 PPEDAIG-LLDLATSYCENRLKKLCQHIIKR 116

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 24 (KLHL24); KLHL24, also called kainate receptor-interacting protein for GluR6 (KRIP6) or protein DRE1, is necessary to maintain the balance between intermediate filament stability and degradation, a process that is essential for skin integrity. KLHL24 is a component of a BCR (BTB-CUL3-RBX1) E3 ubiquitin ligase complex that mediates ubiquitination of KRT14 and controls its levels during keratinocyte differentiation. 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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 204 CCPDIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTLDIpDKTNVGQILNM 283
Cdd:cd18253   17 LFTDVIICVEGREFPCHRAILSACSSYFRAMFCNDHRESREMLVEINGILAEAMDCFLQYVYTGKVKI-TTENVQYLFET 95

                         90       100
                 ....*....|....*....|....*
gi 332221888 284 ADMYGLEGLKEVAIYILRR--DYCN 306
Cdd:cd18253   96 SSLFQISPLRDACAKFLEEqlDPCN 120

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch repeat and BTB domain-containing protein 2 (KBTBD2); KBTBD2, also called BTB and kelch domain-containing protein 1 (BKLHD1), plays an essential role in the regulation of insulin-signaling pathway. It is a BTB-Kelch family substrate recognition subunit of the Cullin-3-based E3 ubiquitin ligase, which targets p85alpha, the regulatory subunit of the phosphoinositol-3-kinase (PI3K) heterodimer, causing p85alpha ubiquitination and proteasome-mediated degradation. 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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 187 EPASELGEDLLKLYVKPCCPDIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYG 266
Cdd:cd18270    8 EYAVSLLEQLKFFYEQQLLTDIVLIVEGTEFPCHKMVLATCSSYFRAMFMSGLSESKQTHVHLRNVDAATLQIIITYAYT 87

                 ....*....
gi 332221888 267 GTLDIPDKT 275
Cdd:cd18270   88 GNLAINDST 96

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch repeat and BTB domain-containing proteins KBTBD6 and KBTBD7; KBTBD6 and KBTBD7 are substrate adaptors of a cullin-3 RING ubiquitin ligase complex that mediates ubiquitylation and proteasomal degradation of T-lymphoma and metastasis gene 1 (TIAM1), a RAC1-specific guanine exchange factor (GEF), by cooperating with gamma-aminobutyric acid receptor-associated proteins (GABARAP). KBTBD7 may also act as a new transcriptional activator in mitogen-activated protein kinase (MAPK) signaling. They both contain 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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 214 GKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTLDIpDKTNVGQILNMADMYGLEGLK 293
Cdd:cd18273   43 GRLFPCNRNVLAAASPYFKSMFTGGLYESKQETVTIHDVDSESMALIIDYCYTGRVTL-SEANVQRLYAAANMLQLEYVR 121

                         90
                 ....*....|
gi 332221888 294 EV-AIYILRR 302
Cdd:cd18273  122 EAcASFLARR 131

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 4 (KLHL4); KLHL4 shares high identity and similarity with the Drosophila kelch protein, a component of ring canals. It may be associated with X-linked cleft palate (CPX) and is also a candidate gene in the impairment of mullerian duct development. In addition, it has been identified as a target of insulin-like growth factor binding protein 5 (IGFBP5). KLHL4 contains a BTB domain and kelch repeat domains, characteristics of a kelch family protein. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 207 DIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTLDIPDKTnVGQILNMADM 286
Cdd:cd18336   21 DVLLIAGNLKIPAHRLVLSAVSDYFAAMFTNDVREAKQEEIKMEGVDPDALKALVHYAYTGVLELKEDT-IESLLAAACL 99

                         90       100
                 ....*....|....*....|....
gi 332221888 287 YGLEGLKEVAiyilrrdyCNFFQK 310
Cdd:cd18336  100 LQLSQVIDVC--------CNFLMK 115

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 20 (KLHL20); KLHL20, also called Kelch-like ECT2-interacting protein (KLEIP) or Kelch-like protein X, is a substrate-specific adaptor of a BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex involved in interferon response and anterograde Golgi to endosome transport. KLHL20 plays a role in actin assembly at cell-cell contact sites of Madin-Darby canine kidney cells. It also controls endothelial migration and sprouting angiogenesis. 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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 207 DIDIFVDGKRFKAHRAILSARSSYFAAMLSGCWAESSQECVNLQGISHVELNVMMHFIYGGTLDIpDKTNVGQILNMADM 286
Cdd:cd18249   25 DVVLVVGAKKIYAHRVILSACSPYFRAMFTGELAESRQTEVTIRDIDERAMELLIDFAYTSQITV-EEGNVQTLLPAACL 103

                         90
                 ....*....|....*.
gi 332221888 287 YGLEGLKEVAIYILRR 302
Cdd:cd18249  104 LQLAEIQEVCCEFLKR 119

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in BTB/POZ domain-containing protein 17 (BTBD17); BTBD17, also called galectin-3-binding protein-like, is a BTB domain-containing protein. Its function remains unclear. It may be associated with hepatocellular carcinoma. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 332221888 194 EDLLKLYVKPCCPDIDIFVDGKRFKAHRAILSARSSYFAAMLS-GCWAESSQecvnlqgiSHVELN----------VMMH 262
Cdd:cd18292    6 QDIAQLYNNEELSDIVLRVGGKVFHAHRLILAKSSDVFRVMLSnDWWSESKQ--------SEIELVedpecaavfeKFLR 77

                         90       100       110
                 ....*....|....*....|....*....|...
gi 332221888 263 FIYGGTLDIpDKTNVGQILNMADMYGLEGLKEV 295
Cdd:cd18292   78 YLYTGQISV-NLETALPLLMLADKYNVTDLKQL 109