PHR domain; This domain is called PHR as it was original found in the proteins PAM, highwire and RPM. This domain can be duplicated in the highwire, PFAM and PRM sequence. The C-terminal region of the protein BTBD1 includes the PHR domain and is known to interact with Topoisomerase I, an enzyme which relaxes DNA supercoils.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039741582 225 HRFQSSAYRsnqWRYRGRC-DSIQFAVDRRVFIAGLGLYGSSSGKAEYSVKIELK------RLGMVLAQNLTKFVSDGSS 297
Cdd:pfam08005   1 NRFQSTGGG---WGYSGGSpDAIRFSVDRDIFLVGFGLYGSIGGPADYSVKIELIdgerweSLGEVLGENDTTFSSDGSN 77

                          90       100       110       120       130       140       150
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1039741582 298 NTFPVWFEHPVQVEQDTFYTASAVLDGSElSYFGQEGMTEVQC-GKVAFQFQCSSDSTNGTGVQGGQIPELIFY 370
Cdd:pfam08005  78 DIFRVLFDEPVEIEPNVKYTASAKIKGPS-SYYGTNGLREVTCdGGVTFQFSSSSLSNNGTSVNRGQIPELLYY 150

PHR domain; This domain is called PHR as it was original found in the proteins PAM, highwire and RPM. This domain can be duplicated in the highwire, PFAM and PRM sequence. The C-terminal region of the protein BTBD1 includes the PHR domain and is known to interact with Topoisomerase I, an enzyme which relaxes DNA supercoils.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039741582 225 HRFQSSAYRsnqWRYRGRC-DSIQFAVDRRVFIAGLGLYGSSSGKAEYSVKIELK------RLGMVLAQNLTKFVSDGSS 297
Cdd:pfam08005   1 NRFQSTGGG---WGYSGGSpDAIRFSVDRDIFLVGFGLYGSIGGPADYSVKIELIdgerweSLGEVLGENDTTFSSDGSN 77

                          90       100       110       120       130       140       150
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1039741582 298 NTFPVWFEHPVQVEQDTFYTASAVLDGSElSYFGQEGMTEVQC-GKVAFQFQCSSDSTNGTGVQGGQIPELIFY 370
Cdd:pfam08005  78 DIFRVLFDEPVEIEPNVKYTASAKIKGPS-SYYGTNGLREVTCdGGVTFQFSSSSLSNNGTSVNRGQIPELLYY 150

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
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039741582    1 MFYGDLAE-VKSEIHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSL 69
Cdd:smart00225  28 LFSSDFKEsDKSEIYLDDVSPEDFRALLNFLYTGKLDLPEENVEELLELADYLQIPGLVELCEEFLLKLL 97

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 1039741582   1 MFYGDLAEV-KSEIHIPDVEPAAFLVLLKYMYSDEIdLEADTVLATLYAAKKYIVPALAKACVNFLETSL 69
Cdd:pfam00651  39 LFSGQESESsVSEITLDDVSPEDFEALLEFMYTGKL-ISEENVDDLLAAADKLQIPSLVDKCEEFLIKSL 107

kelch-like protein; Provisional

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1039741582   1 MFYGDLAEVksEIHIP-DVEpaAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSLEAKNaCV 76
Cdd:PHA03098   40 MFKNNFKEN--EINLNiDYD--SFNEVIKYIYTGKINITSNNVKDILSIANYLIIDFLINLCINYIIKIIDDNN-CI 111

BACK (BTB and C-terminal Kelch) domain found in BTB/POZ domain-containing proteins, BTBD3 and BTBD6; This subfamily includes BTB/POZ domain-containing proteins BTBD3 and BTBD6, both of which are BTB-domain-containing Kelch-like proteins. BTBD3 controls dendrite orientation toward active axons in mammalian neocortex. BTBD6 is required for proper embryogenesis and plays an essential evolutionarily-conserved role during neuronal development.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039741582  69 LEAKNACVLLSQSRLFEEPELTQRCWEVIDAQAEMALRSEGFCEIDRQTLEIIVTREALNTKEAVVFEAVLNWAEAECKR 148
Cdd:cd18488     1 LSARNACVLLSQSRLFEEPELMQRCWEVIDAQAELALKSEGFTEIDYKTLESILRRETLNAKESVVFEAALRWAEAECQR 80

                          90
                  ....*....|....*
gi 1039741582 149 QGLPVTPHNKRHVLG 163
Cdd:cd18488    81 RGLEPTPENKRKVLG 95

BACK (BTB and C-terminal Kelch) domain found in BTB/POZ domain-containing protein 3 (BTBD3); BTBD3 is a BTB-domain-containing Kelch-like protein that controls dendrite orientation toward active axons in mammalian neocortex.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039741582  69 LEAKNACVLLSQSRLFEEPELTQRCWEVIDAQAEMALRSEGFCEIDRQTLEIIVTREALNTKEAVVFEAVLNWAEAECKR 148
Cdd:cd18524     1 LSAKNACVLLSQSCLFEEPDLTQRCWEVIDAQAELALKSEGFCDIDFQTLESILRRETLNAKEIVVFEAALNWAEVECQR 80

                          90
                  ....*....|....*
gi 1039741582 149 QGLPVTPHNKRHVLG 163
Cdd:cd18524    81 QELQPTIENKRKVLG 95

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in BTB/POZ domain-containing proteins, BTBD3 and BTBD6; This family includes BTB/POZ domain-containing proteins BTBD3 and BTBD6, both of which are BTB-domain-containing Kelch-like proteins. BTBD3 controls dendrite orientation toward active axons in mammalian neocortex. BTBD6 is required for proper embryogenesis and plays an essential evolutionary conserved role during neuronal development. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1039741582   1 MFYGDLAEVKSEIHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSL 69
Cdd:cd18282    40 MFYGGLAENKNEIEIPDVEPAAFLNLLRYLYCDEIDLEPDTVLATLYAAKKYLVPHLARACVQFLETSL 108

BACK (BTB and C-terminal Kelch) domain found in BTB/POZ domain-containing proteins, BTBD1 and BTBD2; This subfamily 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 in cell survival. BTBD1 and BTBD2 colocalize to cytoplasmic bodies with the RBCC/tripartite motif protein, TRIM5delta.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039741582  69 LEAKNACVLLSQSRLFEEPELTQRCWEVIDAQAEMALRSEGFCEIDRQTLEIIVTREALNTKEAVVFEAVLNWAEAECKR 148
Cdd:cd18487     1 LSSDNAFMLLTQARLFDEPQLASLCLETIDKNTAEALAAEGFTDIDLDTLCVVLERDTLGIRECKLFQAVLRWAEAECQR 80

                          90
                  ....*....|....*
gi 1039741582 149 QGLPVTPHNKRHVLG 163
Cdd:cd18487    81 QGLSVTPENQRKVLG 95

BACK (BTB and C-terminal Kelch) domain found in BTB/POZ domain-containing protein 1 (BTBD1); BTBD1, also called Hepatitis C virus NS5A-transactivated protein 8 or HCV NS5A-transactivated protein 8, is a BTB-domain-containing Kelch-like protein specifically expressed in skeletal muscle. It interacts with DNA topoisomerase 1 (Topo1), a key enzyme in cell survival. BTBD1 and BTBD2 colocalize to cytoplasmic bodies with the RBCC/tripartite motif protein, TRIM5delta. It may serve as a substrate-specific adaptor of an E3 ubiquitin-protein ligase complex which mediates the ubiquitination and subsequent proteasomal degradation of target proteins.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039741582  69 LEAKNACVLLSQSRLFEEPELTQRCWEVIDAQAEMALRSEGFCEIDRQTLEIIVTREALNTKEAVVFEAVLNWAEAECKR 148
Cdd:cd18522     1 LRADNAFMLLTQARLFDEPQLASLCLDTIDKSTMDAISAEGFTDIDLDTLCAVLERDTLSIRESRLFGAVVRWAEAECQR 80

                          90       100
                  ....*....|....*....|....*..
gi 1039741582 149 QGLPVTPHNKRHVLGRALYLVRIPTMT 175
Cdd:cd18522    81 QQLPVTSENKQKVLGKALSLIRFPLMT 107

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in BTB/POZ domain-containing protein 1 (BTBD1); BTBD1, also called Hepatitis C virus NS5A-transactivated protein 8 or HCV NS5A-transactivated protein 8, is a BTB-domain-containing Kelch-like protein that is expressed in skeletal muscle and interacts 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. BTBD1 may serve as substrate-specific adaptor of an E3 ubiquitin-protein ligase complex that 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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1039741582   1 MFYGDLAEVKSEIHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSLEAKN 73
Cdd:cd18346    61 MFNGGMATTSAEIELPDVEPAAFLALLRFLYSDEVQIGPETVMTTLYTAKKYAVPALEAHCVEFLTKHLRADN 133

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
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039741582    1 MFYGDLAE-VKSEIHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSL 69
Cdd:smart00225  28 LFSSDFKEsDKSEIYLDDVSPEDFRALLNFLYTGKLDLPEENVEELLELADYLQIPGLVELCEEFLLKLL 97

BTB And C-terminal Kelch; The BACK domain is found juxtaposed to the BTB domain; they are separated by as little as two residues.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039741582   75 CV-LLSQSRLFEEPELTQRCWEVIDAQAEMALRSEGFCEIDRQTLEIIVTREALN-TKEAVVFEAVLNWAEAEckrqglp 152
Cdd:smart00875   1 CLgIRRFADAHGLEELAEKALRFILQNFSEVSSSEEFLELPLEQLLELLSSDDLNvSSEEEVFEAVLRWVKHD------- 73

                           90       100
                   ....*....|....*....|....*....
gi 1039741582  153 vtPHNKRHVLGRALYLVRIPTMTLEEFAN 181
Cdd:smart00875  74 --PEKRREHLPELLEHVRLPLLSPDYLLE 100

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
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1039741582   1 MFYGDLAE-VKSEIHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKY 52
Cdd:cd18186    30 MFSSGMKEsSSSEIELDDVSPEAFEALLDYIYTGELELSEENVEELLAAADKL 82

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1039741582   1 MFYGDLAEVKS-EIHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSLEAKN 73
Cdd:cd18237    50 MFTSNMTESKSsEVELKDAEPDIIELLVEFAYTARISVNSNNVQSLLDAANQYQIEPVKKMCVDFLKEQLDASN 123

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1039741582   1 MFYGDLAEVKSE------IHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSLE 70
Cdd:cd18296    46 LLRDHFAESEENngsipvVTLHDVSPEVFAIVLYYIYTDDTDLPPENAYDVLYVADMYLLPGLKRLCGTVLAQSLD 121

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1039741582   1 MFYGDLAEVKSE-IHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSLEAKN 73
Cdd:cd18265    52 MFGGHLKESRQAvVEIQKVSAAAMEVLLDYMYGGGLRIQEDNVESVLEASDLLQVSKLREACVRFLEGQLHPCN 125

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1039741582   4 GDLAEVKsEIHIPDVEPAAFLVLLKYMYSDEIDLEADTVLAT--LYAAKKYIVPALAKACVNFLETSLEAKNaCV 76
Cdd:cd18303    47 ENLASTN-ELDLSDISYEVVLALLRWLYTDELDLTLDDEFLLelMKAAKRFQLTDLVERCERALMSSVNVDN-CI 119

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1039741582  10 KSEIHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSLEAKN 73
Cdd:cd18240    56 KKVYKIPGVSPEMMELIIEYAYTRTVPITAENVEELLPAADQFNIMGIVKACCDFLEDQLCPEN 119

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 41 (KLHL41); KLHL41 is also called Kel-like protein 23, Kelch repeat and BTB domain-containing protein 10 (KBTBD10), Kelch-related protein 1 (Krp1), or sarcosine. It is a novel kelch-related protein that is involved in pseudopod elongation in transformed cells. It is also involved in skeletal muscle development and differentiation. It regulates proliferation and differentiation of myoblasts and plays a role in myofibril assembly by promoting lateral fusion of adjacent thin fibrils into mature, wide myofibrils. 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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1039741582   8 EVKSEIHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSLEAKN 73
Cdd:cd18341    64 EKKKEVVLDNVDPNIMDMILKYLYSAEIDLNDGNVQDIFALASRFQIPSVFTVCVTYLQKRLSPAN 129

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        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1039741582   1 MFYGDLAEVK-SEIHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSLE 70
Cdd:cd18248    54 MFTSGLRECGmEVVPIEGVHPCVMSRLIEFAYTASISVGEKCVLHVLPGAVMYQMDSVVKACCDFLEQQLD 124

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1039741582   1 MFYGDLAEVKS-EIHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLET 67
Cdd:cd18247    48 MFTHDMVESKQdEITMQGIEPSALEALINFAYSGRIAIDTSNVQSLLVGASFLQLQSVKDACCEFLKE 115

BTB And C-terminal Kelch; This domain is found associated with pfam00651 and pfam01344. The BACK domain is found juxtaposed to the BTB domain; they are separated by as little as two residues. This family appears to be closely related to the BTB domain (Finn RD, personal observation).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039741582  87 PELTQRCWEVIDAQAEMALRSEGFCEIDRQTLEIIVTREALNT-KEAVVFEAVLNWAEAECKRqglpvtphnKRHVLGRA 165
Cdd:pfam07707  14 TELAEAALRFILQNFLEVAKSEEFLELSLEQLLELLSSDDLNVpSEEEVFEAVIRWVKHDVER---------RKKHLPEL 84

                          90
                  ....*....|....*.
gi 1039741582 166 LYLVRIPTMTLEEFAN 181
Cdd:pfam07707  85 LSAVRLPLLSPQYLLN 100

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039741582   1 MFYGDLAEVKSE-IHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSL 69
Cdd:cd18339    50 MFTGDMSESKAKkIEIKDVDGQTLSKLIDYIYTAEIEVTEENVQVLLPAASLLQLMDVRQNCCDFLQSQL 119

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1039741582   1 MFYGDLAEV-KSEIHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSLEAKNA 74
Cdd:cd18256    49 LFAGGMSESsKDVVQIHGVEPDIFHILLDFIYTGVVEVTVSNVQELLVAADMLQLTEVVEICCEFLKGQLHPSNC 123

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1039741582   1 MFYGDLAEVKSE-IHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSLEAKNA 74
Cdd:cd18250    50 MFAGELRESRADrVVLHGVSAEILGLLLDFSYTGRVTVTQDNVEALLRAADLFQFPSVKEACCAYLQQRLDVSNC 124

BACK (BTB and C-terminal Kelch) domain found in Drosophila melanogaster serine-enriched protein (GPRS) and similar proteins; The family includes uncharacterized Drosophila melanogaster serine-enriched protein (GPRS) and similar proteins.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1039741582  70 EAKNACVLLSQSRLFEEP----ELTQRCWEVIDAQAEMALRSEGFCEIDRQTLEIIVTREALNTKEAVVFEAVLNWA 142
Cdd:cd18507     1 NVDTVCALLASAERYDQYkctkTLVQKVLEFVDKHGTDVLNLPEFLLLPEHVVRLILSRDSLGADEMTKFQAALAWS 77

BACK (BTB and C-terminal Kelch) domain; The BACK domain is found in architectures C-terminal to a BTB domain, in a diverse set of architectures together with Kelch, MATH, and/or TAZ domains. It is involved in interactions with the Cullin3 (Cul3) ubiquitin ligase complex, as well as in homo-oligomerization. Most proteins containing the BACK domain are understood to function as adaptor proteins that play a role in ubiquitination of various substrates.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1039741582  71 AKNACVLLSQSRLFEEPELTQRCWEVIDAQAEMALRSEGFCEIDRQTLEIIVTR 124
Cdd:cd14733     2 PENCLGILELADLYNLEELKEKALKFILENFEEVSKSEEFLELSVELLLELLSS 55

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
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1039741582   1 MFYGDLAEV-KSEIHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKY 52
Cdd:cd01165    27 LFRGGFRESgQAEINLRDISPEDFRALLEFLYGGKRDLDASNLLELLEAANFL 79

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 2 (KLHL2); KLHL2, also called actin-binding protein Mayven, is a novel actin-binding protein predominantly expressed in the brain. It plays a role in the reorganization of the actin cytoskeleton, and promotes growth of cell projections in oligodendrocyte precursors. KLHL2 is a component of a cullin-RING-based BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex that mediates the ubiquitination of target proteins, such as NPTXR, leading most often to their proteasomal 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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039741582   1 MFYGDLAEVKSE-IHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSL 69
Cdd:cd18338    50 MFTGEMSESRAKrVRIKEVDGWTLKMLIDYVYTAEIQVTEENVQVLLPAAGLLQLQDVKKTCCEFLESQL 119

BACK (BTB and C-terminal Kelch) domain found in Kelch-like protein 35 (KLHL35); KLHL35 belongs to the KLHL family. Its function remains unclear. Hypermethylation of KLHL35 is associated with hepatocellular carcinoma and abdominal aortic aneurysm.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1039741582  69 LEAKNACVLLSQSRLFEEPELTQRCWEVIDAQAEMALRSEGFCEIDRQTLEIIVTREALNTK-EAVVFEAVLNWAEAE 145
Cdd:cd18474     1 IGANNCLALLAAADALHCAPLQEHCIRVLLRDFAQAARHPSFLKLELQLVLELLADDSLAVRsEEVVLEAALRWVDAD 78

BACK (BTB and C-terminal Kelch) domain found in Kelch-like protein 10 (KLHL10); KLHL10 may be a substrate-specific adapter of a CUL3-based E3 ubiquitin-protein ligase complex which mediates the ubiquitination and subsequent proteasomal degradation of target proteins during spermatogenesis.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039741582  75 CVLLSQ-SRLFEEPELTQRCWEVIDAQ-AEMALRSEGFCEIDRQTLEIIVTREALNTK-EAVVFEAVLNW 141
Cdd:cd18450     6 CIGIRKfARYYFCPELERKAYRYILRNfEEVAKDSEEFLELSCEELEDIIEDDELNVKeEEVVFEAIVKW 75

BACK (BTB and C-terminal Kelch) 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 regulating the 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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1039741582  69 LEAKNACVLLSQSRLFEEPELTQRCWEVIDAQAEMALRSEGFCEIDRQTLEIIVTREALNT-KEAVVFEAVLNWAE 143
Cdd:cd18479     1 INAENCVRLLSFADLFSCEELKQSAKRMVEHKFTAVYHQEAFMQLSHDLLIDILSSDNLNVeKEETVREAAMLWLE 76

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 5 (KLHL5); KLHL5 shares high identity and similarity with the Drosophila kelch protein, a component of ring canals. It is abundantly expressed in the ovary, adrenal gland, and thymus. 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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1039741582   1 MFYGDLAEVKSE-IHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSLEAKN 73
Cdd:cd18337    52 MFTNDVREAKQEeIKMEGVEPNALWALVQYAYTGRLELKEDNIECLLSTACLLQLSQVVEACCKFLMKQLHPSN 125

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1039741582  10 KSEIHIPDVEPAAFLVLLKYMYS---DEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSLEAKN 73
Cdd:cd18297    51 TPVIEIPDIRYDIFQLMMQYLYTggvESLDVAQDDALELLRAASFFQLDGLKRHCEILLSQQIDLDN 117

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 6 (KLHL6); KLHL6 is a BTB-kelch protein with a lymphoid tissue-restricted expression pattern. It is involved in B-lymphocyte antigen receptor signaling and germinal center formation. It belongs to the KLHL gene family, which is composed of an N-terminal BTB-POZ domain and four to six Kelch motifs in tandem. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1039741582   1 MFYGDLAEVKSE-IHIPDVEPAAFLVLLKYMYSDEIDLEADTVLATLYAAKKYIVPALAKACVNFLETSLEAKNaCV 76
Cdd:cd18236    53 MFCNDLKEKYEEkIIIKGVDAETMQILLDYTYTSKVLITKQNVQRVLEAASLFQFLRMVDACASFLTEALHPEN-CV 128