BACK (BTB and C-terminal Kelch) domain found in BTB/POZ domain-containing protein 17 (BTBD17); BTBD17, also termed galectin-3-binding protein-like, is a BTB-domain-containing Kelch-like protein. Its function remains unclear. It may be involved in hepatocellular carcinoma development and progression.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 58037273 166 VGPAVGWYHYAVSTGDEALRESCLQFLAWNLSAVAGSAEWGAVSPELLAQLLQRSDLVLQDELELFHALEAWL 238
Cdd:cd18493   2 VNHAVSWLQYAKMCGHKELAEACLEFIAWNFEKVLKSPDWLNLDLDLLVSLLQSSDLVVEDEYTLFQAVEKWL 74

BACK (BTB and C-terminal Kelch) domain found in BTB/POZ domain-containing protein 17 (BTBD17); BTBD17, also termed galectin-3-binding protein-like, is a BTB-domain-containing Kelch-like protein. Its function remains unclear. It may be involved in hepatocellular carcinoma development and progression.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 58037273 166 VGPAVGWYHYAVSTGDEALRESCLQFLAWNLSAVAGSAEWGAVSPELLAQLLQRSDLVLQDELELFHALEAWL 238
Cdd:cd18493   2 VNHAVSWLQYAKMCGHKELAEACLEFIAWNFEKVLKSPDWLNLDLDLLVSLLQSSDLVVEDEYTLFQAVEKWL 74

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 58037273    169 AVGWYHYAVSTGDEALRESCLQFLAWNLSAVAGSAEWGAVSPELLAQLLQRSDLVLQDELELFHALEAWLGRARPP-PTV 247
Cdd:smart00875   1 CLGIRRFADAHGLEELAEKALRFILQNFSEVSSSEEFLELPLEQLLELLSSDDLNVSSEEEVFEAVLRWVKHDPEKrREH 80

                           90       100
                   ....*....|....*....|
gi 58037273    248 AERALRAIRYPMIPPAQLFQ 267
Cdd:smart00875  81 LPELLEHVRLPLLSPDYLLE 100

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 58037273    63 SDVILRVQAvgtdevRAFHTHRLLLGLHSELFRELLSNQ------SEVMLRESRdcAAVFDKFIRYLYCGELtVLLAQAI 136
Cdd:pfam00651  11 CDVTLVVGD------KEFRAHKAVLAACSPYFKALFSGQesessvSEITLDDVS--PEDFEALLEFMYTGKL-ISEENVD 81

                          90       100
                  ....*....|....*....|....*.
gi 58037273   137 PLHRLATKYRVASLQRGVADYMRAHL 162
Cdd:pfam00651  82 DLLAAADKLQIPSLVDKCEEFLIKSL 107

BACK (BTB and C-terminal Kelch) domain found in BTB/POZ domain-containing protein 17 (BTBD17); BTBD17, also termed galectin-3-binding protein-like, is a BTB-domain-containing Kelch-like protein. Its function remains unclear. It may be involved in hepatocellular carcinoma development and progression.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 58037273 166 VGPAVGWYHYAVSTGDEALRESCLQFLAWNLSAVAGSAEWGAVSPELLAQLLQRSDLVLQDELELFHALEAWL 238
Cdd:cd18493   2 VNHAVSWLQYAKMCGHKELAEACLEFIAWNFEKVLKSPDWLNLDLDLLVSLLQSSDLVVEDEYTLFQAVEKWL 74

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 58037273   169 AVGWYHYAVSTGDEALRESCLQFLAWNLSAVAGSAEWGAVSPELLAQLLQRSDLVLQDELELFHALEAWLGRARPP-PTV 247
Cdd:pfam07707   1 CLGIYRFADAYGCTELAEAALRFILQNFLEVAKSEEFLELSLEQLLELLSSDDLNVPSEEEVFEAVIRWVKHDVERrKKH 80

                          90       100
                  ....*....|....*....|...
gi 58037273   248 AERALRAIRYPMIPPAQLFQLQA 270
Cdd:pfam07707  81 LPELLSAVRLPLLSPQYLLNLVE 103

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in zinc finger and BTB domain-containing (ZBTB) proteins, Kelch-like (KLHL) proteins, and similar proteins; This family includes a variety of BTB/POZ domain-containing proteins, such as zinc finger and BTB domain-containing (ZBTB) proteins and Kelch-like (KLHL) proteins. They have diverse functions, such as transcriptional regulation, chromatin remodeling, protein degradation and cytoskeletal regulation. Many BTB/POZ proteins contain one or two additional domains, such as kelch repeats, zinc-finger domains, FYVE (Fab1, YOTB, Vac1, and EEA1) fingers, or ankyrin repeats. These special additional domains or interaction partners provide unique characteristics and functions to BTB/POZ proteins. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 58037273  63 SDVILRVqavgtdEVRAFHTHRLLLGLHSELFRELL------SNQSEVMLREsrDCAAVFDKFIRYLYCGELTVLLAQAI 136
Cdd:cd18186   2 CDVTLVV------GGREFPAHRAVLAARSPYFRAMFssgmkeSSSSEIELDD--VSPEAFEALLDYIYTGELELSEENVE 73

                ....*....
gi 58037273 137 PLHRLATKY 145
Cdd:cd18186  74 ELLAAADKL 82

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 58037273  43 INHSHMLLQRLQDLLRQGNASDVILRVqavgtDEVRaFHTHRLLLGLHSELFRELL------SNQSEVMLRESRdcAAVF 116
Cdd:cd18287   3 IDHVHFLSEDIGALFLNEEYSDVTFVV-----EEKR-FPAHRVILAARSEYFRALLyggmreSQQSEIELKDTN--AEAF 74

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....
gi 58037273 117 DKFIRYLYCGELTVLLAQA---IPLHRLATKYRVASLQRGVADY 157
Cdd:cd18287  75 KALLKYIYTGRLTLTDLKEdvlLDVLGLAHQYGFEELEAAISDY 118

BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in Mac-2-binding protein (MAC2BP/M2BP); M2BP is also called galectin-3-binding protein, basement membrane autoantigen p105, lectin galactoside-binding soluble 3-binding protein (LGALS3BP), or tumor-associated antigen 90K. It promotes integrin-mediated cell adhesion and may stimulate host defense against viruses and tumor cells. It contains a scavenger receptor cysteine-rich domain, followed by BTB and BACK domains. The BTB/POZ domain is a common protein-protein interaction motif of about 100 amino acids.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 58037273  65 VILRVQAVGTDEVRaFHTHRLLLGLHSELFRELLSNQSEVMLRESRDCAAVFDKFIRYLYCGELTVLLAQAIPLHRLATK 144
Cdd:cd18304  22 ISVLTAGGEEEELT-FCAHRVILMLSPEANFLHKTGSSNITLDVDEECLPHVPDFLRYFYTRQIDITLTSVKCFHKLASI 100

                ....*..
gi 58037273 145 YRVASLQ 151
Cdd:cd18304 101 YGVRKLR 107

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

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 58037273  60 GNASDVILRVQAvgtdevRAFHTHRLLLGLHSELFRELLS----NQSEVMLRESRDCAAVFDKFIRYLYCGELTVLLAQA 135
Cdd:cd18295  17 GSYSDVTFNVHG------ESFPAHRCILSARSPYFAEMFEtkwkDKREINLKHPLVNPDAFRALLQYLYTGRLEIHVDDV 90

                        90       100
                ....*....|....*....|....*...
gi 58037273 136 IPLHRLATKYRVASLQRGVADYMRAHLA 163
Cdd:cd18295  91 EDCKRLAKQCRLEELIEELEAKCKKVRE 118

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 58037273  63 SDVILRVqavgtdEVRAFHTHRLLLGLHSELFRELLSN---QSEVMLRESRDCA-AVFDKFIRYLYCG---ELTVLLAQA 135
Cdd:cd18297  13 SDVTFLV------EGRPFYAHKIVLVTASDRFKSMLSSgstEAQTPVIEIPDIRyDIFQLMMQYLYTGgveSLDVAQDDA 86

                        90
                ....*....|....*..
gi 58037273 136 IPLHRLATKYRVASLQR 152
Cdd:cd18297  87 LELLRAASFFQLDGLKR 103

BACK (BTB and C-terminal Kelch) domain found in Drosophila melanogaster protein germ cell-less (GCL) and similar proteins; The GCL protein is a nuclear envelope protein highly conserved between the mammalian and Drosophila orthologs. Drosophila melanogaster GCL is a key regulator required for the specification of pole cells and primordial germ cell formation in Drosophila embryos. Both human germ cell-less protein-like 1 (GMCL1) and germ cell-less protein-like 1-like (GMCL1P1 or GMCL1L) may function in spermatogenesis. They may also be substrate-specific adaptors 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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 58037273 170 VGWYHYAVST-GDEALRESCLQFLAWNLSAVAGSAEWGAVSPELLAQLLQRSDL-VLQDELELFHALEAWL 238
Cdd:cd18495   6 VCSYYEAACMyGLTEVKKKCLEWLLRNLMTSQNVTLLRELSIELMEQLIASPNLfVMQVEMDVYTLLKKWL 76

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 58037273  80 FHTHRLLLGLHSELFRELL------SNQSEVMLREsrDCAAVFDKFIRYLYCGELTV 130
Cdd:cd01165  10 FHVNKELLAQSSEYFRALFrggfreSGQAEINLRD--ISPEDFRALLEFLYGGKRDL 64

BACK (BTB and C-terminal Kelch) domain found in Kelch-like protein 18 (KLHL18); KLHL18 acts as a substrate-specific adaptor for the Cullin3 E3 ubiquitin-protein ligase complex that regulates mitotic entry and ubiquitylates Aurora-A.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 58037273 184 LRESCLQFLAWNLSAVAGSAEWGAVSPELLAQLLQRSDLVLQDELELFHALEAWLGRARppptvAERA------LRAIRY 257
Cdd:cd18457  21 LVDAANKYIQQHFIEVSKSEEFLALSKEEVLEILSRDELNVKSEEQVFEAALAWVKYDR-----ENREeylpelLSKVRL 95

                ....*
gi 58037273 258 PMIPP 262
Cdd:cd18457  96 PLLRP 100

BACK (BTB and C-terminal Kelch) domain found in Kelch-like proteins, KLHL9 and KLHL13; KLHL9 and KLHL13 (also termed BTB and kelch domain-containing protein 2, or BKLHD2) are substrate-specific adaptors of a BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex required for mitotic progression and cytokinesis. The BCR(KLHL9-KLHL13) E3 ubiquitin ligase complex mediates the ubiquitination of AURKB and controls the dynamic behavior of AURKB on mitotic chromosomes and thereby coordinates faithful mitotic progression and completion of cytokinesis.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 58037273 191 FLAWNLSAVAGSAEWGAVSPELLAQLLQRSDLVLQDELELFHALEAWLGRARPPPTVAERALRAIRYP 258
Cdd:cd18449  28 FILKNFPALLSTGDFVKLPFERLAFVLSSNSLKGCTELELFKAACRWLRHEDDRMQFAAKLMENIRFP 95