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 24660969  53 ISAHKFILSASSQFFATMFETapiTNPNGVLYVVLPpDLSHRAIQILVQYMYSGEATVSNDILNEVLRGGEILKIRG 129
Cdd:cd18315  13 LKAHKLVLAAASPYFAALLKE---TPPDEHPVIILP-DVPYSELKALLDFIYTGEVNVSQEQLESLLKLAELLQIKG 85

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 24660969  53 ISAHKFILSASSQFFATMFETapiTNPNGVLYVVLPpDLSHRAIQILVQYMYSGEATVSNDILNEVLRGGEILKIRG 129
Cdd:cd18315  13 LKAHKLVLAAASPYFAALLKE---TPPDEHPVIILP-DVPYSELKALLDFIYTGEVNVSQEQLESLLKLAELLQIKG 85

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 24660969     53 ISAHKFILSASSQFFATMFETAPITNPNGVLYVvlpPDLSHRAIQILVQYMYSGEATVSNDILNEVLRGGEILKIRGL 130
Cdd:smart00225  11 FHAHKAVLAAHSPYFKALFSSDFKESDKSEIYL---DDVSPEDFRALLNFLYTGKLDLPEENVEELLELADYLQIPGL 85

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 24660969  53 ISAHKFILSASSQFFATMFETapiTNPNGVLYVVLPpDLSHRAIQILVQYMYSGEATVSNDILNEVLRGGEILKIRG 129
Cdd:cd18315  13 LKAHKLVLAAASPYFAALLKE---TPPDEHPVIILP-DVPYSELKALLDFIYTGEVNVSQEQLESLLKLAELLQIKG 85

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 24660969    24 LYKNEKFADVVLYSSYNSsgipsdiptvgISAHKFILSASSQFFATMFETAPITNPNGVLYvvlPPDLSHRAIQILVQYM 103
Cdd:pfam00651   4 LREQGELCDVTLVVGDKE-----------FRAHKAVLAACSPYFKALFSGQESESSVSEIT---LDDVSPEDFEALLEFM 69

                          90       100
                  ....*....|....*....|....*..
gi 24660969   104 YSGEaTVSNDILNEVLRGGEILKIRGL 130
Cdd:pfam00651  70 YTGK-LISEENVDDLLAAADKLQIPSL 95

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 24660969     53 ISAHKFILSASSQFFATMFETAPITNPNGVLYVvlpPDLSHRAIQILVQYMYSGEATVSNDILNEVLRGGEILKIRGL 130
Cdd:smart00225  11 FHAHKAVLAAHSPYFKALFSSDFKESDKSEIYL---DDVSPEDFRALLNFLYTGKLDLPEENVEELLELADYLQIPGL 85

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 24660969  13 HLTYLNSSIATLYKNEKFADVVLyssynssgipsdipTVG---ISAHKFILSASSQFFATMfetapitnpngvLY----- 84
Cdd:cd18287   5 HVHFLSEDIGALFLNEEYSDVTF--------------VVEekrFPAHRVILAARSEYFRAL------------LYggmre 58

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....
gi 24660969  85 -----VVLpPDLSHRAIQILVQYMYSGEATVSN---DILNEVLR 120
Cdd:cd18287  59 sqqseIEL-KDTNAEAFKALLKYIYTGRLTLTDlkeDVLLDVLG 101

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in BTB/POZ domain-containing protein 18 (BTBD18); BTBD18 acts as a specific controller for transcription activation through RNA polymerase II elongation at a subset of genomic PIWI-interacting RNA (piRNA) loci. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 24660969  52 GISAHKFILSASSQFFATMFETAPITNPNGVLYVVlpPDLSHRAIQILVQYMYSGEATVSNDILNEVLRGGEILKIRGL 130
Cdd:cd18293  26 SVPAHCCVLSACSPYLTERLSSEPPPAGQKVVLEL--QGLKAHTLLKLVDFLYTSELEVSSEEAQDVLAAARRLQISEL 102

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 24660969  24 LYKNEKFADVVLYssynssgipsdIPTVGISAHKFILSASSQFFATMFETAPITNPNgvlYVVLPPDLSHRAIQILVQYM 103
Cdd:cd18237  15 MRKQKTLCDVILI-----------VEGREIKAHRVVLAAASHFFHLMFTSNMTESKS---SEVELKDAEPDIIELLVEFA 80

                        90       100
                ....*....|....*....|....
gi 24660969 104 YSGEATVSNDILNEVLRGGEILKI 127
Cdd:cd18237  81 YTARISVNSNNVQSLLDAANQYQI 104

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 24660969  10 WDSHLTYLNSSIATLYKNEKFADV--VLYSSYNSSGIPsdiptvgisAHKFILSASSQFFATMFETAPITNPNGVLYvvl 87
Cdd:cd18281   2 WQASKTTVKERFAFLFNNETLSDVhfIVGKGDNEQRIP---------AHKFVLSIGSAVFDAMFNGGMATTSAEIEL--- 69

                        90       100
                ....*....|....*....|...
gi 24660969  88 pPDLSHRAIQILVQYMYSGEATV 110
Cdd:cd18281  70 -PDVEPAAFLALLRFLYSDEVQI 91

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 24660969  55 AHKFILSASSQFFATMFETAPITNPNGVLYVvlpPDLSHRAIQILVQYMYSG---EATVSNDILNEVLRGGEILKIRGLC 131
Cdd:cd18297  26 AHKIVLVTASDRFKSMLSSGSTEAQTPVIEI---PDIRYDIFQLMMQYLYTGgveSLDVAQDDALELLRAASFFQLDGLK 102

                .
gi 24660969 132 R 132
Cdd:cd18297 103 R 103

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 8 (KLHL8); KLHL8 is a substrate-specific adaptor of a BCR (BTB-CUL3-RBX1) E3 ubiquitin ligase complex required for the ubiquitination and degradation of rapsyn, a postsynaptic protein required for clustering of nicotinic acetylcholine receptors (nAChRs) at the neuromuscular junction. 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 24660969  19 SSIATLYKNEKFADVVLyssynssgipsdipTVG---ISAHKFILSASSQFFATMFeTAPITNPNgvLYVVLPPDLSHRA 95
Cdd:cd18238   4 KVLHQFYENGELCDVTL--------------KVGeksIHCHRLVLACVSPYFRAMF-TSEMAESK--QDSITIKDIDEEA 66

                        90       100       110
                ....*....|....*....|....*....|..
gi 24660969  96 IQILVQYMYSGEATVSNDILNEVLRGGEILKI 127
Cdd:cd18238  67 VELLVDFAYTGKLTLTVDNVQSLLYAASLLQV 98

BTB (Broad-Complex, Tramtrack and Bric a brac) /POZ (poxvirus and zinc finger) domain found in Drosophila melanogaster centrosomal protein 190kD (CP190) and similar proteins; CP190 is a large, multi-domain protein, first identified as a centrosome protein with oscillatory localization over the course of the cell cycle. It has an essential function in the nucleus as a chromatin insulator. It is known to associate with the nuclear matrix, components of the RNAi machinery, active promoters and borders of the repressive chromatin domains. CP190 contains an N-terminal 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 24660969  21 IATLYKNEKFADVVLYSSYNSSgipsdiptvgISAHKFILSASSQFFATMFETAPITNPNgvlyVVLPPDLSHRAIQILV 100
Cdd:cd18311   5 LQNLFNKTEYCDLTLQFRDNEQ----------LKVHRLVLSACTDYFNVLEQTCEIVDDT----LIMPNELQADAVVPVI 70

                        90       100
                ....*....|....*....|....*..
gi 24660969 101 QYMYSGEATVSNDILNEVLRGGEILKI 127
Cdd:cd18311  71 NFMYTGQLEFEEKSYGKLLRTAKELNM 97

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in BTB/POZ domain-containing protein 6 (BTBD6); BTBD6, also termed lens BTB domain protein, is a BTB-domain-containing Kelch-like protein 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        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 24660969  24 LYKNEKFADVvlYSSYNSSGIPSDIPtvgisAHKFILSASSQFFATMFeTAPITNPNGVLYVvlpPDLSHRAIQILVQYM 103
Cdd:cd18349   2 MFNNELMADV--HFIVGPPGASQRVP-----AHKYVLAVGSSVFYAMF-YGDLAEVKSEIHI---PDVEPAAFLILLKYM 70

                        90
                ....*....|
gi 24660969 104 YSGEATVSND 113
Cdd:cd18349  71 YSDEIDLEAD 80

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch repeat and BTB domain-containing protein 3 (KBTBD3); KBTBD3, also called BTB and kelch domain-containing protein 3 (BKLHD3), 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
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 24660969  53 ISAHKFILSASSQFFATMFETAPITNPNGvlyVVLPPDLSHRAIQILVQYMYSGEATVSND 113
Cdd:cd18271  36 IPCHRCVLAACSDFFRAMFEVNMKERDDG---SVTISNLSPKAVKAFLDYAYTGKAEITDD 93

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        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 24660969  10 WDSHLTYLNSSIATLYKNEKFADVVLYSSYNSSGIPSDIPTvGISAHKFILSASSQFFATMFETAPITNPNGVLYvvlpP 89
Cdd:cd18346   2 WQATKSSLKERFAFLFNNELLSDVRFVVGKGRPRGPGPGAQ-RIPAHRFVLAAGSAVFDAMFNGGMATTSAEIEL----P 76

                        90       100
                ....*....|....*....|.
gi 24660969  90 DLSHRAIQILVQYMYSGEATV 110
Cdd:cd18346  77 DVEPAAFLALLRFLYSDEVQI 97

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 24660969  53 ISAHKFILSASSQFFATMFETAPITNPNGVLYVVLpPDLSHRAIQILVQYMYSGEATVSNDILNEVLRGGEIL 125
Cdd:cd18245  26 IPVQKNVLAAASPYFRAKLNYNPPKDDGSTYKIEL-EGISVEVMEEILDYIYTGQIKLSEDNIQDIVQAADLL 97

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 24660969  11 DSHLTYLNSSIATLYKNEKFADVVLysSYNSSGIPsdiptvgisAHKFILSASSQFFATMFetapiTN---PNGVLYVVL 87
Cdd:cd18242   2 NSHAKSILNTMNSLRKSNTLCDVTL--RVEGKEFP---------AHRIVLAACSDYFCAMF-----TSemsEKGKSEVEL 65

                        90       100       110       120
                ....*....|....*....|....*....|....*....|..
gi 24660969  88 pPDLSHRAIQILVQYMYSGEATVSNDILNEVLRGGEILKIRG 129
Cdd:cd18242  66 -QGLTASTMEILLDFVYTETVHVTVENVQELLPAACLLQLKG 106

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in zinc finger and BTB domain-containing protein 24 (ZBTB24); ZBTB24, also called zinc finger protein 450, functions as a transcription factor essentially involved in B-cell functions in humans. The loss-of-function mutations in ZBTB24 can cause ICF2 (immunodeficiency, centromeric instability and facial anomalies syndrome 2) with immunological characteristics of greatly reduced serum antibodies and circulating memory B cells. ZBTB24 contains a BTB/POZ domain, a common protein-protein interaction motif of about 100 amino acids.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 24660969  51 VGISAHKFILSASSQFFATMFetAPITNPNGVLYVVlpPDLSHRAIQILVQYMYSGEATVSNDILNEVLRGGEILKIRGL 130
Cdd:cd18212  33 VQFRAHKALLAASSEYFSMMF--ADEGEVGQSIYML--EGMVAETFGALLEFIYTGCLQVGEKSLEQILATAQFLKVNDL 108

                ..
gi 24660969 131 CR 132
Cdd:cd18212 109 VK 110

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Kelch-like protein 23 (KLHL23); KLHL23 overexpression is associated with increased cell proliferation and invasion in gastric cancer. Downregulation of KLHL23 is associated with invasion, metastasis, and poor prognosis of hepatocellular carcinoma and pancreatic cancer. KLHL23 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 24660969  12 SHLTYLNSSIATLYKNEKFADVVLYSSynsSGIPsdiptvgISAHKFILSASSQFFATMFETAPITNPNGVLYVvlpPDL 91
Cdd:cd18252   3 SHPADFLDAFRTFYLDGLFTDITLQCA---SGQI-------FHCHKAALAACSSYFKVMFTADMKEKSNNVIKL---SGI 69

                        90       100       110
                ....*....|....*....|....*....|....*
gi 24660969  92 SHRAIQILVQYMYSGEATVSNDILNEVLRGGEILK 126
Cdd:cd18252  70 DHDILEALVNYVYTSQICITERNVQSLLEAADLLQ 104

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

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*....
gi 24660969  53 ISAHKFILSASSQFFATMFETAPITNPNGVLYVVLPPDL-----SHRAIQILVQYMYSG 106
Cdd:cd18310  31 VPVHRCILAARSPFFRDIFASAKAEGANTKPKLELRELIpggivGYDAFMLVLSYLYSG 89

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.

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gi 24660969  12 SHLTYLNSSIATLYKNEKFADVVLyssynsSGIPSDIPtvgisAHKFILSASSQFFATMFetAPITNPNGVLYVVLpPDL 91
Cdd:cd18250   3 AHALHLLRGLSELRAERKFFDVTL------CAGGREFP-----CHRTVLAAASSYFRAMF--AGELRESRADRVVL-HGV 68

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                ....*....|....*....|....*....|....*
gi 24660969  92 SHRAIQILVQYMYSGEATVSNDILNEVLRGGEILK 126
Cdd:cd18250  69 SAEILGLLLDFSYTGRVTVTQDNVEALLRAADLFQ 103