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 944081706 186 HLAELLHNKTGTDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVLEfGL 265
Cdd:cd18280    4 HFGALLESEEGADVTFNVDGEKFRAHKLVLAARSPVFRSMLFGPMREENEGEIVIEDVEPPVFKALLHFIYKDELPD-DV 82

                         90       100       110
                 ....*....|....*....|....*....|....*....
gi 944081706 266 QH------EAVTMLAQHLLAAADRYGLDRLKEICQGKLS 298
Cdd:cd18280   83 EPagsdssSLDTTMAQHLLAAADRYALERLRLLCESRLC 121

MATH (meprin and TRAF-C homology) domain; an independent folding unit with an eight-stranded beta-sandwich structure found in meprins, TRAFs and other proteins. Meprins comprise a class of extracellular metalloproteases which are anchored to the membrane and are capable of cleaving growth factors, extracellular matrix proteins, and biologically active peptides. TRAF molecules serve as adapter proteins that link cell surface receptors of the Tumor Necrosis Factor and 1nterleukin-1/Toll-like families to downstream kinase cascades, which results in the activation of transcription factors and the regulation of cell survival, proliferation and stress responses in the immune and inflammatory systems. Other members include the ubiquitin ligases, TRIM37 and SPOP, and the ubiquitin-specific proteases, HAUSP and Ubp21p. A large number of uncharacterized members mostly from lineage-specific expansions in C. elegans and rice contain MATH and BTB domains, similar to SPOP. The MATH domain has been shown to bind peptide/protein substrates in TRAFs and HAUSP. It is possible that the MATH domain in other members of this superfamily also interacts with various protein substrates. The TRAF domain may also be involved in the trimerization of TRAFs. Based on homology, it is postulated that the MATH domain in meprins may be involved in its tetramer assembly and that the MATH domain, in general, may take part in diverse modular arrangements defined by adjacent multimerization domains.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 944081706  18 LKIDGYcaakTMGNEDCIKSSC-SVGGYDWEICIYPamvppdRRARDRTPWVVVKLVFLSETCPSI---VRANLSCRLVD 93
Cdd:cd00121    5 WKIVNF----SELEGESIYSPPfEVGGYKWRIRIYP------NGDGESGDYLSLYLELDKGESDLEkwsVRAEFTLKLVN 74

                         90       100       110       120       130       140
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 944081706  94 PRGvlGPSPEKSVSCIFNRSwisrclemcspfVNEDCSLPVCLKsTGELAASGYLRNDSFTVQCTIT 160
Cdd:cd00121   75 QNG--GKSLSKSFTHVFFSE------------KGSGWGFPKFIS-WDDLEDSYYLVDDSLTIEVEVK 126

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 944081706 186 HLAELLHNKTGTDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVLEfGL 265
Cdd:cd18280    4 HFGALLESEEGADVTFNVDGEKFRAHKLVLAARSPVFRSMLFGPMREENEGEIVIEDVEPPVFKALLHFIYKDELPD-DV 82

                         90       100       110
                 ....*....|....*....|....*....|....*....
gi 944081706 266 QH------EAVTMLAQHLLAAADRYGLDRLKEICQGKLS 298
Cdd:cd18280   83 EPagsdssSLDTTMAQHLLAAADRYALERLRLLCESRLC 121

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 944081706   198 DVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVLefgLQHEAVtmlaQHL 277
Cdd:smart00225   1 DVTLVVGGKKFHAHKAVLAAHSPYFKALFSSDFKESDKSEIYLDDVSPEDFRALLNFLYTGKLD---LPEENV----EEL 73

                           90       100
                   ....*....|....*....|....
gi 944081706   278 LAAADRYGLDRLKEICQGKLSDGI 301
Cdd:smart00225  74 LELADYLQIPGLVELCEEFLLKLL 97

MATH (meprin and TRAF-C homology) domain; an independent folding unit with an eight-stranded beta-sandwich structure found in meprins, TRAFs and other proteins. Meprins comprise a class of extracellular metalloproteases which are anchored to the membrane and are capable of cleaving growth factors, extracellular matrix proteins, and biologically active peptides. TRAF molecules serve as adapter proteins that link cell surface receptors of the Tumor Necrosis Factor and 1nterleukin-1/Toll-like families to downstream kinase cascades, which results in the activation of transcription factors and the regulation of cell survival, proliferation and stress responses in the immune and inflammatory systems. Other members include the ubiquitin ligases, TRIM37 and SPOP, and the ubiquitin-specific proteases, HAUSP and Ubp21p. A large number of uncharacterized members mostly from lineage-specific expansions in C. elegans and rice contain MATH and BTB domains, similar to SPOP. The MATH domain has been shown to bind peptide/protein substrates in TRAFs and HAUSP. It is possible that the MATH domain in other members of this superfamily also interacts with various protein substrates. The TRAF domain may also be involved in the trimerization of TRAFs. Based on homology, it is postulated that the MATH domain in meprins may be involved in its tetramer assembly and that the MATH domain, in general, may take part in diverse modular arrangements defined by adjacent multimerization domains.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 944081706  18 LKIDGYcaakTMGNEDCIKSSC-SVGGYDWEICIYPamvppdRRARDRTPWVVVKLVFLSETCPSI---VRANLSCRLVD 93
Cdd:cd00121    5 WKIVNF----SELEGESIYSPPfEVGGYKWRIRIYP------NGDGESGDYLSLYLELDKGESDLEkwsVRAEFTLKLVN 74

                         90       100       110       120       130       140
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 944081706  94 PRGvlGPSPEKSVSCIFNRSwisrclemcspfVNEDCSLPVCLKsTGELAASGYLRNDSFTVQCTIT 160
Cdd:cd00121   75 QNG--GKSLSKSFTHVFFSE------------KGSGWGFPKFIS-WDDLEDSYYLVDDSLTIEVEVK 126

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 944081706 186 HLAELLHNKTGTDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVLEfGL 265
Cdd:cd18280    4 HFGALLESEEGADVTFNVDGEKFRAHKLVLAARSPVFRSMLFGPMREENEGEIVIEDVEPPVFKALLHFIYKDELPD-DV 82

                         90       100       110
                 ....*....|....*....|....*....|....*....
gi 944081706 266 QH------EAVTMLAQHLLAAADRYGLDRLKEICQGKLS 298
Cdd:cd18280   83 EPagsdssSLDTTMAQHLLAAADRYALERLRLLCESRLC 121

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in speckle-type POZ protein-like (SPOPL); SPOPL, also called HIB homolog 2 or Roadkill homolog 2, is a component of a cullin-RING-based BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complexes that mediate the ubiquitination and subsequent proteasomal degradation of target proteins. The complexes may contain homodimeric SPOPL or the heterodimers formed by speckle-type POZ protein (SPOP) and SPOPL, which are less efficient than ubiquitin ligase complexes containing only SPOP. 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 944081706 183 LQHHLAELLHNKTGTDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVle 262
Cdd:cd18343    8 LAEDLGNLWENSRFTDCSLFVGGQEFKAHKSILAARSPVFNAMFEHEMEESKKNRVEINDVDPEVFKEMMRFIYTGKA-- 85

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|..
gi 944081706 263 fglqhEAVTMLAQHLLAAADRYGLDRLKEICQGKLSDGISVD 304
Cdd:cd18343   86 -----PNLDKMADNLLAAADKYALERLKVMCEEALCNNLSVE 122

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in BTB/POZ domain-containing protein 9 (BTBD9); BTBD9 is a risk factor for Restless Legs Syndrome (RLS) encoding a Cullin-3 substrate adaptor. The BTBD9 gene may be associated with antipsychotic-induced RLS in schizophrenia. Mutations in BTBD9 lead to reduced dopamine, increased locomotion and sleep fragmentation. 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 944081706 182 SLQHHLAELLHNKTGTDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTdSVL 261
Cdd:cd18287    8 FLSEDIGALFLNEEYSDVTFVVEEKRFPAHRVILAARSEYFRALLYGGMRESQQSEIELKDTNAEAFKALLKYIYT-GRL 86

                         90       100       110
                 ....*....|....*....|....*....|....
gi 944081706 262 EFGLQHEAVTMlaqHLLAAADRYGLDRLKE-ICQ 294
Cdd:cd18287   87 TLTDLKEDVLL---DVLGLAHQYGFEELEAaISD 117

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 944081706 183 LQHHLAELLHNKTGTDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVle 262
Cdd:cd18344   10 LTDDLGELWENSLFTDCCLLVAGHEFRAHKAILAARSPVFRAMFEHEMEERLKNPIEIHDLDPQVFKEMMGFIYTGKA-- 87

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....
gi 944081706 263 fglQHEAVTMLAQHLLAAADRYGLDRLKEICQGKLSDGISVDTA 306
Cdd:cd18344   88 ---PHLHSHSMACDVLAAADKYGLEGLKVLCEDALCRNLSVENA 128

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Ankyrin repeat and BTB/POZ domain-containing protein 2 (ABTB2) and similar proteins; This family includes ABTB2, BTBD11, plant ARM repeat protein interacting with ABF2 (ARIA), and similar proteins. ABTB2, also called bood POZ containing gene type 2 (BPOZ-2), is a scaffold protein that controls the degradation of many biological proteins ranging from embryonic development to tumor progression. It may be involved in the initiation of hepatocyte growth. ABTB2 functions as an adaptor protein for the E3 ubiquitin ligase scaffold protein Cullin-3. It directly binds to eukaryotic elongation factor 1A1 (eEF1A1) to promote eEF1A1 ubiquitylation and degradation, and prevent translation. The BTBD11 gene has been recently identified as an all-trans retinoic acid (atRA)-responsive gene that lies downstream of atRA and its receptors in the regulation of neurite outgrowth and cell adhesion in neural as well as non-neural tissues. 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. 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 944081706 188 AELLHNKTGTDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVLEFGLQH 267
Cdd:cd18297    4 PHYVNNPEMSDVTFLVEGRPFYAHKIVLVTASDRFKSMLSSGSTEAQTPVIEIPDIRYDIFQLMMQYLYTGGVESLDVAQ 83

                         90       100       110
                 ....*....|....*....|....*....|....*...
gi 944081706 268 EAvtmlAQHLLAAADRYGLDRLKEICQGKLSDGISVDT 305
Cdd:cd18297   84 DD----ALELLRAASFFQLDGLKRHCEILLSQQIDLDN 117

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 944081706   198 DVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVLefgLQHEAVtmlaQHL 277
Cdd:smart00225   1 DVTLVVGGKKFHAHKAVLAAHSPYFKALFSSDFKESDKSEIYLDDVSPEDFRALLNFLYTGKLD---LPEENV----EEL 73

                           90       100
                   ....*....|....*....|....
gi 944081706   278 LAAADRYGLDRLKEICQGKLSDGI 301
Cdd:smart00225  74 LELADYLQIPGLVELCEEFLLKLL 97

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 944081706 187 LAELLHNKTGTDVTFLV--SGKSFAAHKLILAARSPVLMAEFF-GHMKETSSQHVEINEIEAVVFKALLYFIYTDSVLEF 263
Cdd:cd18294    5 MKSLINNPEFSDVKFLVgpERQEIFAHKCILAARCEVFRAMFLtGPQKESTQSPLVLSDIEPEVFRAVLEFIYTNCVTLS 84

                         90       100       110
                 ....*....|....*....|....*....|.
gi 944081706 264 GlqHEAVtmlaqHLLAAADRYGLDRLKEICQ 294
Cdd:cd18294   85 N--HTVI-----EVLAAAVEYGLDELRKLCE 108

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in intracisternal A particle-promoted polypeptide (IPP); IPP, also called Kelch-like protein 27 (KLHL27) or actin-binding protein IPP, is an actin-binding protein that may play a role in organizing the actin cytoskeleton. 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 944081706 198 DVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVlefglqhEAVTMLAQHL 277
Cdd:cd18256   22 DVQLQVGMELFSVHRLVLAASSPYFAALFAGGMSESSKDVVQIHGVEPDIFHILLDFIYTGVV-------EVTVSNVQEL 94

                         90
                 ....*....|....*.
gi 944081706 278 LAAADRYGLDRLKEIC 293
Cdd:cd18256   95 LVAADMLQLTEVVEIC 110

BTB (Broad-Complex, Tramtrack and Bric a brac) /POZ (poxvirus and zinc finger) domain found in Dictyostelium discoideum trishanku and similar proteins; Trishanku is a novel regulator required for normal morphogenesis and cell-type stability in Dictyostelium discoideum. It contains a 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 944081706 193 NKTGTDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVlefGLQHEAVTm 272
Cdd:cd18314    3 DSEFSDVVLCVGDRKFFAHRIVLCARSPVFRSMLTGSMIESNLKEVTLEDVEPEIFETVLKYMYTGQV---TLSEENVL- 78

                         90       100
                 ....*....|....*....|.
gi 944081706 273 laqHLLAAADRYGLDRLKEIC 293
Cdd:cd18314   79 ---DLLMLASKYQVPDLEKLC 96

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in BTB/POZ domain-containing proteins, BTBD1 and BTBD2; This family includes BTB/POZ domain-containing proteins BTBD1 and BTBD2, both of which are BTB-domain-containing Kelch-like proteins that interact with DNA topoisomerase 1 (Topo1), a key enzyme of cell survival. BTBD1 and BTBD2 colocalize to cytoplasmic bodies with the RBCC/tripartite motif protein, TRIM5delta. 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 944081706 179 SSPSLQHHLAELLHNKTGTDVTFLV----SGKSFAAHKLILAARSPVLMAEFFGHMKETSSQhVEINEIEAVVFKALLYF 254
Cdd:cd18281    5 SKTTVKERFAFLFNNETLSDVHFIVgkgdNEQRIPAHKFVLSIGSAVFDAMFNGGMATTSAE-IELPDVEPAAFLALLRF 83

                         90       100       110       120       130       140       150
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 944081706 255 IYTDsvlefglqheavtmlaqhllaaadrygldrlkEICqgklsdgISVDTAATTLALAEQHNCPQLKAKCVEFI 329
Cdd:cd18281   84 LYSD--------------------------------EVQ-------IGPETVMTTLYTAKKYAVPALESACVEFL 119

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 944081706 189 ELLHNKTGTDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVlefGLQHE 268
Cdd:cd18237   14 NMRKQKTLCDVILIVEGREIKAHRVVLAAASHFFHLMFTSNMTESKSSEVELKDAEPDIIELLVEFAYTARI---SVNSN 90

                         90       100
                 ....*....|....*....|....*
gi 944081706 269 AVtmlaQHLLAAADRYGLDRLKEIC 293
Cdd:cd18237   91 NV----QSLLDAANQYQIEPVKKMC 111

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 944081706 197 TDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQH-----VEINEIEAVVFKALLYFIYTDSVlefglqhEAVT 271
Cdd:cd18296   18 PDVCFQVEGHRFPCHKAFFCGRSDYFKALLRDHFAESEENNgsipvVTLHDVSPEVFAIVLYYIYTDDT-------DLPP 90

                         90       100
                 ....*....|....*....|..
gi 944081706 272 MLAQHLLAAADRYGLDRLKEIC 293
Cdd:cd18296   91 ENAYDVLYVADMYLLPGLKRLC 112

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 26 (KLHL26); KLHL26 is encoded by the klhl26 gene, which is regulated by p53 via fuzzy tandem repeats. 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 944081706 180 SPSLQHHLAELLHNKTGTDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDS 259
Cdd:cd18255    2 SVTLLQGLNALRAKGQLLDVTLIADGQRFQAHKVVLASCSDYFRAMFTGGMRESSQDEIELKGVSAKGLKHILDFAYTSE 81

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*.
gi 944081706 260 VlefGLQHEAVtmlaQHLLAAADRYGLDRLKEICQGKLSDGISVDT 305
Cdd:cd18255   82 L---TLDLDCI----QDVLGAAVHLQMLPVVELCEEFLKSAMSVEN 120

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 21 (KLHL21); KLHL21 is a substrate-specific adaptor of a BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex required for efficient chromosome alignment and cytokinesis. The BCR(KLHL21) E3 ubiquitin ligase complex regulates localization of the chromosomal passenger complex (CPC) from chromosomes to the spindle midzone in anaphase and mediates the ubiquitination of aurora B. KLHL21 also targets IkappaB kinase-beta to regulate nuclear factor kappa-light chain enhancer of activated B cells (NF-kappaB) signaling negatively. 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 944081706 182 SLQHHLAELLHNKTGTDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVl 261
Cdd:cd18250    7 HLLRGLSELRAERKFFDVTLCAGGREFPCHRTVLAAASSYFRAMFAGELRESRADRVVLHGVSAEILGLLLDFSYTGRV- 85

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*
gi 944081706 262 efGLQHEAVtmlaQHLLAAADRYGLDRLKEICQGKLSDGISVDTA 306
Cdd:cd18250   86 --TVTQDNV----EALLRAADLFQFPSVKEACCAYLQQRLDVSNC 124

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 944081706 199 VTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVlefglqHEAVTMLAQHLL 278
Cdd:cd01165    1 VVLVVEGEKFHVNKELLAQSSEYFRALFRGGFRESGQAEINLRDISPEDFRALLEFLYGGKR------DLDASNLLELLE 74

                 ..
gi 944081706 279 AA 280
Cdd:cd01165   75 AA 76

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in RCC1 and BTB domain-containing proteins, RCBTB1 and RCBTB2; The RCC1-related guanine nucleotide exchange factor (GEF) family includes RCC1 and BTB domain-containing proteins, RCBTB1 and RCBTB2, both of which are chromosome condensation regulator-like guanine nucleotide exchange factors. They contain 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 944081706 185 HHLAELLHNKTGTDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVlEFG 264
Cdd:cd18298    1 DSLRKAFNDPRTSDLKFRVDGKYIYVHKAILKIRCEYFRSMFQSHWNEDDKNVIEIDQYSYPVYYAFLRYLYTDQV-DLP 79

                         90       100       110
                 ....*....|....*....|....*....|
gi 944081706 265 lQHEAVTMLaqHLlaaADRYGLDRLKEICQ 294
Cdd:cd18298   80 -PEDAIGLL--DL---ANSYCEERLKKLCE 103

first BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in inhibitor of Bruton tyrosine kinase (IBtk); IBtk is an inhibitor or negative regulator of Bruton tyrosine kinase (Btk), which is required for B-cell differentiation and development. IBtk binds to the PH domain of Btk and down-regulates the Btk kinase activity. It contains 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 944081706 183 LQHHLAELLHNKTGTD----VTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQ----HVEINEIEAVVFKALLYF 254
Cdd:cd18301    1 FQEDFKKLLDEADEGDnihdVVFQVGGKTFPAHKFILASRSDYFRKLFLSSLLTSEDAvgcdVVHIEKVPPEIFEQLLQF 80

                 ....*
gi 944081706 255 IYTDS 259
Cdd:cd18301   81 IYTDT 85

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 12 (KLHL12); KLHL12, also called CUL3-interacting protein 1 (C3IP1) or DKIR homolog, is a substrate-specific adaptor of a BCR (BTB-CUL3-RBX1) E3 ubiquitin ligase complex that acts as a negative regulator of the Wnt signaling pathway and ER-Golgi transport. 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 944081706 198 DVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVLefglqheaVTML-AQH 276
Cdd:cd18242   23 DVTLRVEGKEFPAHRIVLAACSDYFCAMFTSEMSEKGKSEVELQGLTASTMEILLDFVYTETVH--------VTVEnVQE 94

                         90
                 ....*....|....*..
gi 944081706 277 LLAAADRYGLDRLKEIC 293
Cdd:cd18242   95 LLPAACLLQLKGVKQAC 111

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Ankyrin repeat and BTB/POZ domain-containing protein 2 (ABTB2); ABTB2, also called bood POZ containing gene type 2 (BPOZ-2), is a scaffold protein that controls the degradation of many biological proteins with various functions ranging from embryonic development to tumor progression. It may be involved in the initiation of hepatocyte growth. It inhibits the aggregation of alpha-synuclein, with implications for Parkinson's disease. ABTB2 functions as an adaptor protein for the E3 ubiquitin ligase scaffold protein Cullin-3. It directly binds to eukaryotic elongation factor 1A1 (eEF1A1) to promote eEF1A1 ubiquitylation and degradation, and prevent translation. It is also involved in the growth suppressive effect of the phosphatase and tensin homolog (PTEN). It contains an ankyrin repeat, BTB/POZ, and BACK domains. 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 944081706 191 LHNKTGTDVTFLVSGKSFAAHKLILAARSpvlmAEFFGHMKETSSQH------VEINEIEAVVFKALLYFIY---TDSVl 261
Cdd:cd18350   19 LNNKEMSDVTFLVEGKLFYAHKVLLVTAS----NRFKSLLTNKSEQEsqgsktIEISDIKYHIFQMLMQYLYyggTESM- 93

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*..
gi 944081706 262 efglqhEAVTMLAQHLLAAADRYGLDRLKEICQGKLSDGISVDTAAT 308
Cdd:cd18350   94 ------EIPIADVLELLSAASLFQLDALQRHCEILCSQTINLENAVN 134

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 944081706 197 TDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVLefgLQHEAVtmlaQH 276
Cdd:cd18265   24 TDVVLLVDGKDFPCHRATLSANSAYFRAMFGGHLKESRQAVVEIQKVSAAAMEVLLDYMYGGGLR---IQEDNV----ES 96

                         90
                 ....*....|....*..
gi 944081706 277 LLAAADRYGLDRLKEIC 293
Cdd:cd18265   97 VLEASDLLQVSKLREAC 113

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in gigaxonin; Gigaxonin, also called Kelch-like protein 16 (KLHL16), may be a cytoskeletal component that directly or indirectly plays an important role in neurofilament architecture. It may also act as a substrate-specific adaptor of an E3 ubiquitin-protein ligase complex which mediates the ubiquitination and subsequent proteasomal degradation of target proteins, including tubulin folding cofactor B (TBCB), microtubule-associated protein MAP1B, and glial fibrillary acidic protein (GFAP). Gigaxonin is mutated in giant axonal neuropathy. 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 944081706 198 DVTFLVSGKSFAAHKLILAARSPVLMAEFFGH--MKETSSQHVEINEIEAVVFKALLYFIYTDSVLefgLQHEAVtmlaQ 275
Cdd:cd18245   16 DATLVVGGEEIPVQKNVLAAASPYFRAKLNYNppKDDGSTYKIELEGISVEVMEEILDYIYTGQIK---LSEDNI----Q 88

                         90
                 ....*....|....*...
gi 944081706 276 HLLAAADRYGLDRLKEIC 293
Cdd:cd18245   89 DIVQAADLLLMTDLKDLC 106

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 944081706 198 DVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVlefglqhEAVTMLAQHL 277
Cdd:cd18247   21 DVTLKVGDQKFSAHRIVLAATIPYFHAMFTHDMVESKQDEITMQGIEPSALEALINFAYSGRI-------AIDTSNVQSL 93

                         90
                 ....*....|....*.
gi 944081706 278 LAAADRYGLDRLKEIC 293
Cdd:cd18247   94 LVGASFLQLQSVKDAC 109

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 944081706 197 TDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTDSVlefGLQHEAvtmlAQH 276
Cdd:cd18353   21 SDLKFRVDGKYIHVHKAVLKIRCEHFRTMFQSHWNEDMKEVIEIDQFSYPVYRAFLEYLYTDSV---DLPPED----AIG 93

                         90
                 ....*....|....*...
gi 944081706 277 LLAAADRYGLDRLKEICQ 294
Cdd:cd18353   94 LLDLATSYCENRLKKLCQ 111

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 3 (KLHL3); KLHL3 is a component of an E3 ubiquitin ligase complex that regulates blood pressure by targeting With-No-Lysine (WNK) kinases for degradation. It 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 944081706 187 LAELLHNKTGTDVTFLVSGKSFAAHKLILAARSPVLMAEFFGHMKETSSQHVEINEIEAVVFKALLYFIYTdsvLEFGLQ 266
Cdd:cd18339   12 MNELRSKQLLCDVTIVAEDVEIEAHRVVLAACSPYFCAMFTGDMSESKAKKIEIKDVDGQTLSKLIDYIYT---AEIEVT 88