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 1958761025 211 LKVPECRLAEDLGNLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFV 290
Cdd:cd18343     1 LKVPECRLAEDLGNLWENSRFTDCSLFVGGQEFKAHKSILAARSPVFNAMFEHEMEESKKNRVEINDVDPEVFKEMMRFI 80

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|...
gi 1958761025 291 YTGKAPNLDKMADNLLAAADKYALERLKVMCEEALCSNLSVEN 333
Cdd:cd18343    81 YTGKAPNLDKMADNLLAAADKYALERLKVMCEEALCNNLSVEN 123

BACK (BTB and C-terminal Kelch) domain found in speckle-type POZ protein-like (SPOPL); SPOPL, also termed HIB homolog 2, or Roadkill homolog 2, is a component of a cullin-RING-based BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex that mediates the ubiquitination and subsequent proteasomal degradation of target proteins. The complexes containing homodimeric SPOPL or the heterodimer formed by speckle-type POZ protein (SPOP) and SPOPL are less efficient than ubiquitin ligase complexes containing only SPOP.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1958761025 329 LSVENVADTLVLADLHSAEQLKAQAIDFINRCSVLRQLGCKDGKNWNNNQATDIMETSGWKSMIQSRPHLVAEAFRALAS 408
Cdd:cd18519     1 LSVENVADTLILADLHSAEQLKAQAIDFINRCSVLRQLGCKDGKNWNSNHATDIMETAGWKSMIHSHPHLVAEAFRALAS 80

                          90
                  ....*....|....*.
gi 1958761025 409 SQCPQFGIPRKRLKQS 424
Cdd:cd18519    81 AQCPPFGIPRKRLKQS 96

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 1958761025 211 LKVPECRLAEDLGNLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFV 290
Cdd:cd18343     1 LKVPECRLAEDLGNLWENSRFTDCSLFVGGQEFKAHKSILAARSPVFNAMFEHEMEESKKNRVEINDVDPEVFKEMMRFI 80

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|...
gi 1958761025 291 YTGKAPNLDKMADNLLAAADKYALERLKVMCEEALCSNLSVEN 333
Cdd:cd18343    81 YTGKAPNLDKMADNLLAAADKYALERLKVMCEEALCNNLSVEN 123

BACK (BTB and C-terminal Kelch) domain found in speckle-type POZ protein-like (SPOPL); SPOPL, also termed HIB homolog 2, or Roadkill homolog 2, is a component of a cullin-RING-based BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex that mediates the ubiquitination and subsequent proteasomal degradation of target proteins. The complexes containing homodimeric SPOPL or the heterodimer formed by speckle-type POZ protein (SPOP) and SPOPL are less efficient than ubiquitin ligase complexes containing only SPOP.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1958761025 329 LSVENVADTLVLADLHSAEQLKAQAIDFINRCSVLRQLGCKDGKNWNNNQATDIMETSGWKSMIQSRPHLVAEAFRALAS 408
Cdd:cd18519     1 LSVENVADTLILADLHSAEQLKAQAIDFINRCSVLRQLGCKDGKNWNSNHATDIMETAGWKSMIHSHPHLVAEAFRALAS 80

                          90
                  ....*....|....*.
gi 1958761025 409 SQCPQFGIPRKRLKQS 424
Cdd:cd18519    81 AQCPPFGIPRKRLKQS 96

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 1958761025  233 DCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYTGKAPNLDKMADNLLAAADKY 312
Cdd:smart00225   1 DVTLVVGGKKFHAHKAVLAAHSPYFKALFSSDFKESDKSEIYLDDVSPEDFRALLNFLYTGKLDLPEENVEELLELADYL 80

                           90
                   ....*....|....*..
gi 1958761025  313 ALERLKVMCEEALCSNL 329
Cdd:smart00225  81 QIPGLVELCEEFLLKLL 97

meprin and TRAF homology;

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1958761025   36 WTINNFSfcREEMGEVLKSSTFSSGpndKMKWCLRVNPKG--------LDEESRDYlslylllvscPKSEVRAKFKFSLL 107
Cdd:smart00061   4 HTFKNVS--RLEEGESYFSPSEEHF---NIPWRLKIYRKNgflslylhCEKEECDS----------RKWSIEAEFTLKLV 68

                           90       100       110
                   ....*....|....*....|....*....|
gi 1958761025  108 NAkreETKAMESQRAYRFVQGKDWGFKKFI 137
Cdd:smart00061  69 SQ---NGKSLSKKDKHVFEKPSGWGFSKFI 95

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 1958761025 211 LKVPECRLAEDLGNLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFV 290
Cdd:cd18343     1 LKVPECRLAEDLGNLWENSRFTDCSLFVGGQEFKAHKSILAARSPVFNAMFEHEMEESKKNRVEINDVDPEVFKEMMRFI 80

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|...
gi 1958761025 291 YTGKAPNLDKMADNLLAAADKYALERLKVMCEEALCSNLSVEN 333
Cdd:cd18343    81 YTGKAPNLDKMADNLLAAADKYALERLKVMCEEALCNNLSVEN 123

Speckle-type POZ protein (SPOP) family, MATH domain; composed of proteins with similarity to human SPOP. SPOP was isolated as a novel antigen recognized by serum from a scleroderma patient, whose overexpression in COS cells results in a discrete speckled pattern in the nuclei. It contains an N-terminal MATH domain and a C-terminal BTB (also called POZ) domain. Together with Cul3, SPOP constitutes an ubiquitin E3 ligase which is able to ubiquitinate the PcG protein BMI1, the variant histone macroH2A1 and the death domain-associated protein Daxx. Therefore, SPOP may be involved in the regulation of these proteins and may play a role in transcriptional regulation, apoptosis and X-chromosome inactivation. Cul3 binds to the BTB domain of SPOP whereas Daxx and the macroH2A1 nonhistone region have been shown to bind to the MATH domain. Both MATH and BTB domains are necessary for the nuclear speckled accumulation of SPOP. There are many proteins, mostly uncharacterized, containing both MATH and BTB domains from C. elegans and plants which are excluded from this family.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1958761025  28 KVVKFSYMWTINNFSFCREEMGEVLKSSTFSSGPNDKMKWCLRVNPKGLDEESRDYLSLYLLLVSCPKSEVRAKFKFSLL 107
Cdd:cd03774     1 KVVKFCYMWTISNFSFCREEMGEVIKSSTFSSGANDKLKWCLRVNPKGLDEESKDYLSLYLLLVSCPKSEVRAKFKFSIL 80

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1958761025 108 NAKREETKAMESQRAYRFVQGKDWGFKKFIRRDFLLDEANGLLPDDKLTLFCE 160
Cdd:cd03774    81 NAKGEETKAMESQRAYRFVQGKDWGFKKFIRRDFLLDEANGLLPDDKLTLFCE 133

BACK (BTB and C-terminal Kelch) domain found in speckle-type POZ protein-like (SPOPL); SPOPL, also termed HIB homolog 2, or Roadkill homolog 2, is a component of a cullin-RING-based BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex that mediates the ubiquitination and subsequent proteasomal degradation of target proteins. The complexes containing homodimeric SPOPL or the heterodimer formed by speckle-type POZ protein (SPOP) and SPOPL are less efficient than ubiquitin ligase complexes containing only SPOP.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1958761025 329 LSVENVADTLVLADLHSAEQLKAQAIDFINRCSVLRQLGCKDGKNWNNNQATDIMETSGWKSMIQSRPHLVAEAFRALAS 408
Cdd:cd18519     1 LSVENVADTLILADLHSAEQLKAQAIDFINRCSVLRQLGCKDGKNWNSNHATDIMETAGWKSMIHSHPHLVAEAFRALAS 80

                          90
                  ....*....|....*.
gi 1958761025 409 SQCPQFGIPRKRLKQS 424
Cdd:cd18519    81 AQCPPFGIPRKRLKQS 96

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 1958761025 211 LKVPECRLAEDLGNLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFV 290
Cdd:cd18344     3 IKDPRHMLTDDLGELWENSLFTDCCLLVAGHEFRAHKAILAARSPVFRAMFEHEMEERLKNPIEIHDLDPQVFKEMMGFI 82

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|....*
gi 1958761025 291 YTGKAPNLD--KMADNLLAAADKYALERLKVMCEEALCSNLSVEN 333
Cdd:cd18344    83 YTGKAPHLHshSMACDVLAAADKYGLEGLKVLCEDALCRNLSVEN 127

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 1958761025 222 LGNLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYTGKAPNLDKM 301
Cdd:pfam00651   1 LNELREQGELCDVTLVVGDKEFRAHKAVLAACSPYFKALFSGQESESSVSEITLDDVSPEDFEALLEFMYTGKLISEENV 80

                          90       100
                  ....*....|....*....|....*...
gi 1958761025 302 ADnLLAAADKYALERLKVMCEEALCSNL 329
Cdd:pfam00651  81 DD-LLAAADKLQIPSLVDKCEEFLIKSL 107

BACK (BTB and C-terminal Kelch) domain found in speckle-type POZ protein (SPOP) and similar proteins; This family includes speckle-type POZ protein (SPOP), speckle-type POZ protein-like (SPOPL), TD and POZ domain-containing proteins (TDPOZ), Drosophila melanogaster protein roadkill, and similar proteins. Both SPOP and SPOPL serve as adaptors of cullin-RING-based BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex that mediates the ubiquitination and proteasomal degradation of target proteins. TDPOZ is a family of bipartite animal and plant proteins that contain a tumor necrosis factor receptor-associated factor (TRAF) domain (TD) and a POZ/BTB domain. TDPOZ proteins may be nuclear scaffold proteins involved in transcription regulation in early development and other cellular processes. Drosophila melanogaster protein roadkill, also termed 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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1958761025 329 LSVENVADTLVLADLHSAEQLKAQAIDFINRCsvlrqlgckdgknwnnnqATDIMETSGWKSMIQSRPHLVAEAFRA 405
Cdd:cd14821     1 LSVENAAEVLVLADLHSAEQLKTHAIDFINSH------------------ATDVMETEGWKSMVRSHPHLVAEAFRA 59

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 1958761025 218 LAEDLGNLWENTRFTDCCFFV--RGKEFKAHKSVLAARSPVFNAMF-EHEMEECTKNRVEINDLDPEVFKEMMRFVYTGK 294
Cdd:cd18294     1 FAADMKSLINNPEFSDVKFLVgpERQEIFAHKCILAARCEVFRAMFlTGPQKESTQSPLVLSDIEPEVFRAVLEFIYTNC 80

                          90       100
                  ....*....|....*....|....*....
gi 1958761025 295 APNLDKMADNLLAAADKYALERLKVMCEE 323
Cdd:cd18294    81 VTLSNHTVIEVLAAAVEYGLDELRKLCER 109

BACK (BTB and C-terminal Kelch) domain found in speckle-type POZ protein (SPOP); SPOP, also termed HIB homolog 1, or Roadkill homolog 1, is a novel nuclear speckle-type protein which serves as an adaptor of cullin-RING-based BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex that mediates the ubiquitination and proteasomal degradation of target proteins, such as BRMS1, DAXX, PDX1/IPF1, GLI2 and GLI3.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1958761025 329 LSVENVADTLVLADLHSAEQLKAQAIDFINRcsvlrqlgckdgknwnnnQATDIMETSGWKSMIQSRPHLVAEAFRALAS 408
Cdd:cd18518     1 LSVENAAEILILADLHSADQLKTQAVDFINY------------------HASDVMETSGWKSMVVSHPHLVAEAYRSLAS 62

                  ....*....
gi 1958761025 409 SQCPQFGIP 417
Cdd:cd18518    63 AQCPFLGPP 71

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 1958761025 227 ENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYTGKAPNLDKMAD--- 303
Cdd:cd18297     8 NNPEMSDVTFLVEGRPFYAHKIVLVTASDRFKSMLSSGSTEAQTPVIEIPDIRYDIFQLMMQYLYTGGVESLDVAQDdal 87

                          90       100       110
                  ....*....|....*....|....*....|
gi 1958761025 304 NLLAAADKYALERLKVMCEEALCSNLSVEN 333
Cdd:cd18297    88 ELLRAASFFQLDGLKRHCEILLSQQIDLDN 117

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 1958761025 227 ENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYTGKA-PNLDKMADnL 305
Cdd:cd18314     2 NDSEFSDVVLCVGDRKFFAHRIVLCARSPVFRSMLTGSMIESNLKEVTLEDVEPEIFETVLKYMYTGQVtLSEENVLD-L 80

                          90
                  ....*....|....*.
gi 1958761025 306 LAAADKYALERLKVMC 321
Cdd:cd18314    81 LMLASKYQVPDLEKLC 96

second 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 second 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 1958761025 216 CRLAEDLGNLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYtGKA 295
Cdd:cd18286     2 SRLGKDLLQLFLNGEDSDITIKVDGKTFKAHRCILCARSSYFAAMLSGSWAESNSSEITLTGVSHAAVSFVLLFIY-GGV 80

                          90       100
                  ....*....|....*....|....*
gi 1958761025 296 PNLDKMAD--NLLAAADKYALERLK 318
Cdd:cd18286    81 LDLPDDVNlgELLSLADMYGLDGLK 105

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 1958761025 217 RLAEDLG---NLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYTG 293
Cdd:cd18237     4 LLADFMGvmnNMRKQKTLCDVILIVEGREIKAHRVVLAAASHFFHLMFTSNMTESKSSEVELKDAEPDIIELLVEFAYTA 83

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|
gi 1958761025 294 KAPNLDKMADNLLAAADKYALERLKVMCEEALCSNLSVEN 333
Cdd:cd18237    84 RISVNSNNVQSLLDAANQYQIEPVKKMCVDFLKEQLDASN 123

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 1958761025 222 LGNLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYTGKapnLDKM 301
Cdd:cd18256    11 LNKLRGQHEFCDVQLQVGMELFSVHRLVLAASSPYFAALFAGGMSESSKDVVQIHGVEPDIFHILLDFIYTGV---VEVT 87

                          90       100       110
                  ....*....|....*....|....*....|....*
gi 1958761025 302 ADN---LLAAADKYALERLKVMCEEALCSNLSVEN 333
Cdd:cd18256    88 VSNvqeLLVAADMLQLTEVVEICCEFLKGQLHPSN 122

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in rabankyrin-5 (Rank-5); Rank-5, also called ankyrin repeat and FYVE domain-containing protein 1 (ANKFY1) or ankyrin repeats hooked to a zinc finger motif (ANKHZN), is a Rab5 effector that regulates and coordinates different endocytic mechanisms. It contains an N-terminal BTB domain, followed by a BACK domain, several ankyrin (ANK) repeats and a C-terminal FYVE 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 1958761025 217 RLAEDLGNLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAmfeheMEECTKNRVEINDLDPEVFKEMMRFVYTGKAP 296
Cdd:cd18303     4 RLLKTVASLFDKELYSDITIKLADKSIPAHKFVLAARSEKWSN-----ENLASTNELDLSDISYEVVLALLRWLYTDELD 78

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|.
gi 1958761025 297 nlDKMADN----LLAAADKYALERLKVMCEEALCSNLSVEN 333
Cdd:cd18303    79 --LTLDDEflleLMKAAKRFQLTDLVERCERALMSSVNVDN 117

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 30 (KLHL30); KLHL30 contains a BTB domain and kelch repeats, characteristics of a kelch family 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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1958761025 220 EDLGNLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYTGK 294
Cdd:cd18259    21 DGLQTLRSNPKLSDVTLLVGGREFPCHRSVLALCSHYFNAMFTGDFVESISARVEIKDVDPAVMESLIDFAYTGK 95

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 1958761025 222 LGNLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYTGK-APNLDK 300
Cdd:cd18255     9 LNALRAKGQLLDVTLIADGQRFQAHKVVLASCSDYFRAMFTGGMRESSQDEIELKGVSAKGLKHILDFAYTSElTLDLDC 88

                          90       100       110
                  ....*....|....*....|....*....|...
gi 1958761025 301 MADnLLAAADKYALERLKVMCEEALCSNLSVEN 333
Cdd:cd18255    89 IQD-VLGAAVHLQMLPVVELCEEFLKSAMSVEN 120

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Influenza virus NS1A-binding protein (NS1-BP); NS1-BP is also called NS1-binding protein, aryl hydrocarbon receptor-associated protein 3 (ARA3), or IVNS1ABP. It is a novel protein that interacts with the influenza A virus nonstructural NS1 protein, which is relocalized in the nuclei of infected cells. It plays a role in cell division and in the dynamic organization of the actin skeleton as a stabilizer of actin filaments by association with F-actin through its kelch repeats. It also interacts with alpha-enolase/MBP-1 and is involved in c-Myc gene transcriptional control. NS1-BP contains BTB and BACK domains at the N-terminal region and kelch repeats at the C-terminal region. 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 1958761025 220 EDLGNLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYTGKapnLD 299
Cdd:cd18306     7 AKLNALRKNRQFCDVILQVGGHEIPAHRAVLACASPYLFELFSSDSDGESILTVKLDGLDPDAVEVLVNYAYTSR---LE 83

                          90       100       110
                  ....*....|....*....|....*....|....*..
gi 1958761025 300 KMAD---NLLAAADKYALERLKVMCEEALCSNLSVEN 333
Cdd:cd18306    84 VPADlvkSVYSAAKKLKMDRVKKACGDFLLEKLTPQN 120

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like proteins, KLHL40 and KLHL41; This family includes Kelch-like proteins, KLHL40 and KLHL41. KLHL40 is a substrate-specific adaptor of a BCR (BTB-CUL3-RBX1) E3 ubiquitin ligase complex that acts as a key regulator of skeletal muscle development. KLHL41 is a novel kelch related protein that is involved in pseudopod elongation in transformed cells. 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 1958761025 218 LAEDLGNLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYTGKAPN 297
Cdd:cd18269    14 LQDGLKDLLDENKFVDCVLKIGDKEFPCHRLVLAACSPYFRAMFLSDLEESKKKEVVLEDVDPDVMGMILKYLYTSEIDL 93

                          90       100       110
                  ....*....|....*....|....*....|....*.
gi 1958761025 298 LDKMADNLLAAADKYALERLKVMCEEALCSNLSVEN 333
Cdd:cd18269    94 NDQNVQDIFALASRFQIPSIFTVCVSYLQKRLSLSN 129

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 1958761025 233 DCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYTGKAPNLDKMADNLLAAADKY 312
Cdd:cd18247    21 DVTLKVGDQKFSAHRIVLAATIPYFHAMFTHDMVESKQDEITMQGIEPSALEALINFAYSGRIAIDTSNVQSLLVGASFL 100

                          90
                  ....*....|...
gi 1958761025 313 ALERLKVMCEEAL 325
Cdd:cd18247   101 QLQSVKDACCEFL 113

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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1958761025 241 KEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYTG 293
Cdd:cd18248    35 EEFMAHKVVLASSSPYFKAMFTSGLRECGMEVVPIEGVHPCVMSRLIEFAYTA 87

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 1958761025 218 LAEDLGNLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHE--MEECTKNRVEINDLDPEVFKEMMRFVYTGKA 295
Cdd:cd18245     1 LLRALNSFREEPHLCDATLVVGGEEIPVQKNVLAAASPYFRAKLNYNppKDDGSTYKIELEGISVEVMEEILDYIYTGQI 80

                          90       100       110
                  ....*....|....*....|....*....|.
gi 1958761025 296 P-NLDKMADnLLAAADKYALERLKVMCEEAL 325
Cdd:cd18245    81 KlSEDNIQD-IVQAADLLLMTDLKDLCCEFL 110

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 25 (KLHL25); KLHL25, also called ectoderm-neural cortex protein 2 (ENC-2), is a substrate-specific adaptor of a BCR (BTB-CUL3-RBX1) E3 ubiquitin ligase complex that is required for translational homeostasis. The BCR(KLHL25) ubiquitin ligase complex acts by mediating ubiquitination of hypophosphorylated EIF4EBP1 (4E-BP1). Cullin3-KLHL25 ubiquitin ligase also targets ATP-citrate lyase (ACLY), a key enzyme for lipid synthesis, for degradation to inhibit lipid synthesis and tumor progression. KLHL25 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 1958761025 214 PECRLAEdLGNLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEIND-LDPEVFKEMMRFVYT 292
Cdd:cd18254     6 PDCVLTH-LNTLRKQCMFTDVTLWAGNRSFPCHRAVLAACSRYFEAMFSNGLRESLDSTVNFHDsLHPEVLELLLDFAYS 84

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|.
gi 1958761025 293 GKAPNLDKMADNLLAAADKYALERLKVMCEEALCSNLSVEN 333
Cdd:cd18254    85 SRIIINEENAESLLEAGDMLQFHDVRDAAAEFLEKNLYPSN 125

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 1958761025 218 LAEDLGNLWENTRFTDCcFFVRGKE-----FKAHKSVLAARSPVFNAMFEHEMEEcTKNRVEINDLDPEVFKEMMRFVYT 292
Cdd:cd18281     9 VKERFAFLFNNETLSDV-HFIVGKGdneqrIPAHKFVLSIGSAVFDAMFNGGMAT-TSAEIELPDVEPAAFLALLRFLYS 86

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|....
gi 1958761025 293 GKapnLDKMADNL---LAAADKYALERLKVMCEEALCSNLSVEN 333
Cdd:cd18281    87 DE---VQIGPETVmttLYTAKKYAVPALESACVEFLKKNLSSDN 127

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 17 (KLHL17); KLHL17, also called actinfilin, is a substrate-recognition component of some cullin-RING-based BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complexes. It acts as a Cullin 3 (Cul3) substrate adaptor that links GLUR6 to the E3 ubiquitin-ligase complex, and mediates the ubiquitination and subsequent degradation of GLUR6. It may play a role in actin-based neuronal function. 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 1958761025 233 DCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYTGKAPNLDKMADNLLAAADKY 312
Cdd:cd18246    41 DIVLHVGTKEIKAHKVVLASCSPYFHAMFTNEMSESRQTHVTLHDIDPQALEQLVQYAYTAEIVVGEGNVQTLLPAASLL 120

                          90
                  ....*....|....*..
gi 1958761025 313 ALERLKVMCEEALCSNL 329
Cdd:cd18246   121 QLNGVRDACCKFLLSQL 137

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 1958761025 218 LAEDLGNLWENTRFTDCCFFVRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYTGKAPN 297
Cdd:cd18270    13 LLEQLKFFYEQQLLTDIVLIVEGTEFPCHKMVLATCSSYFRAMFMSGLSESKQTHVHLRNVDAATLQIIITYAYTGNLAI 92

                          90       100       110
                  ....*....|....*....|....*....|....*.
gi 1958761025 298 LDKMADNLLAAADKYALERLKVMCEEALCSNLSVEN 333
Cdd:cd18270    93 NDSTVEQLYETACFLQVEDVLQRCREYLIKKINAEN 128

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1958761025 238 VRGKEFKAHKSVLAARSPVFNAMFEHEMEECTKNRVEINDLDPEVFKEMMRFVYTGKAPNLDKMADNLLAAADKY 312
Cdd:cd01165     5 VEGEKFHVNKELLAQSSEYFRALFRGGFRESGQAEINLRDISPEDFRALLEFLYGGKRDLDASNLLELLEAANFL 79