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 18409761   2 MIKGMAEDDC-ADNGIPLPNVTSKILLLVIEYCKKHVV----------ESKEEDLKKWDAEFMKKmEQSILFDVMMAANY 70
Cdd:cd18322  24 TIKNMLEDLGyDDDPIPLPNVTSKILKKVIEWCEHHKDdpppeidldsEKRTDDIPEWDAEFLKV-DQDTLFELILAANY 102

                        90
                ....*....|
gi 18409761  71 LNIQSLLDLT 80
Cdd:cd18322 103 LDIKGLLDLT 112

BTB (Broad-Complex, Tramtrack and Bric a brac) /POZ (poxvirus and zinc finger) domain found in S-phase kinase-associated protein 1 (SKP1) and similar proteins; SKP1 is also called cyclin-A/CDK2-associated protein p19 (p19A), organ of Corti protein 2 (OCP-2), organ of Corti protein II (OCP-II), RNA polymerase II elongation factor-like protein, transcription elongation factor B polypeptide 1-like, or p19skp1. It is an essential component of the SCF (SKP1-CUL1-F-box protein) ubiquitin ligase complex, which mediates the ubiquitination of proteins involved in cell cycle progression, signal transduction and transcription. SKP1 serves as an adaptor protein that links the F-box protein to CUL1. SKP1 and CUL1 are invariant components of all SCF complexes, while F-box proteins are variable substrate binding modules that determine specificity. SKP1 belongs to the BTB/POZ domain family; the domain is a common protein-protein interaction motif of about 100 amino acids.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 18409761   2 MIKGMAEDDC-ADNGIPLPNVTSKILLLVIEYCKKHVV----------ESKEEDLKKWDAEFMKKmEQSILFDVMMAANY 70
Cdd:cd18322  24 TIKNMLEDLGyDDDPIPLPNVTSKILKKVIEWCEHHKDdpppeidldsEKRTDDIPEWDAEFLKV-DQDTLFELILAANY 102

                        90
                ....*....|
gi 18409761  71 LNIQSLLDLT 80
Cdd:cd18322 103 LDIKGLLDLT 112

SCF ubiquitin ligase, SKP1 component [Posttranslational modification, protein turnover, chaperones];

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 18409761   1 MMIKGMAEDDCADN-GIPLPNVTSKILLLVIEYCKKHVVESKEE----DLKK------WDAEFMKkMEQSILFDVMMAAN 69
Cdd:COG5201  25 ILIKNMLCDSTACNyPIPAPNVRSSVLMKVQEWMEHHTSSLSEDendlEIRKskpsdfWDRFFME-VDQEMLLEICLAAN 103

                        90
                ....*....|
gi 18409761  70 YLNIQSLLDL 79
Cdd:COG5201 104 YLEIKPLLDL 113

BTB (Broad-Complex, Tramtrack and Bric a brac) /POZ (poxvirus and zinc finger) domain found in S-phase kinase-associated protein 1 (SKP1) and similar proteins; SKP1 is also called cyclin-A/CDK2-associated protein p19 (p19A), organ of Corti protein 2 (OCP-2), organ of Corti protein II (OCP-II), RNA polymerase II elongation factor-like protein, transcription elongation factor B polypeptide 1-like, or p19skp1. It is an essential component of the SCF (SKP1-CUL1-F-box protein) ubiquitin ligase complex, which mediates the ubiquitination of proteins involved in cell cycle progression, signal transduction and transcription. SKP1 serves as an adaptor protein that links the F-box protein to CUL1. SKP1 and CUL1 are invariant components of all SCF complexes, while F-box proteins are variable substrate binding modules that determine specificity. SKP1 belongs to the BTB/POZ domain family; the domain is a common protein-protein interaction motif of about 100 amino acids.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 18409761   2 MIKGMAEDDC-ADNGIPLPNVTSKILLLVIEYCKKHVV----------ESKEEDLKKWDAEFMKKmEQSILFDVMMAANY 70
Cdd:cd18322  24 TIKNMLEDLGyDDDPIPLPNVTSKILKKVIEWCEHHKDdpppeidldsEKRTDDIPEWDAEFLKV-DQDTLFELILAANY 102

                        90
                ....*....|
gi 18409761  71 LNIQSLLDLT 80
Cdd:cd18322 103 LDIKGLLDLT 112

SCF ubiquitin ligase, SKP1 component [Posttranslational modification, protein turnover, chaperones];

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 18409761   1 MMIKGMAEDDCADN-GIPLPNVTSKILLLVIEYCKKHVVESKEE----DLKK------WDAEFMKkMEQSILFDVMMAAN 69
Cdd:COG5201  25 ILIKNMLCDSTACNyPIPAPNVRSSVLMKVQEWMEHHTSSLSEDendlEIRKskpsdfWDRFFME-VDQEMLLEICLAAN 103

                        90
                ....*....|
gi 18409761  70 YLNIQSLLDL 79
Cdd:COG5201 104 YLEIKPLLDL 113

BTB (Broad-Complex, Tramtrack and Bric a brac) /POZ (poxvirus and zinc finger) domain found in Elongin-C (EloC) and similar proteins; Elongin-C is also called elongin 15 kDa subunit, RNA polymerase II transcription factor SIII subunit C, SIII p15, or transcription elongation factor B polypeptide 1 (TCEB1). It is a component of SIII (also known as elongin), which is a general transcription elongation factor that increases the RNA polymerase II transcription elongation past template-encoded arresting sites. It forms a regulatory complex with subunit B or elongin-B (BC) that enhances the activity of the transcriptionally active subunit A. The BC complex also functions as an adaptor protein in the proteasomal degradation of target proteins via different E3 ubiquitin ligase complexes, including the von Hippel-Lindau ubiquitination complex CBC (VHL) and the suppressors of cytokine signaling (SOCS) box ubiquitin ligase family. Elongin-C belongs to the BTB/POZ domain family; the domain is a common protein-protein interaction motif of about 100 amino acids.

                       10        20        30        40        50        60        70
               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 18409761  2 MIKGM-----AEDDCADNGIPLPNVTSKILLLVIEYCKKHV-VESKEEDLKKWDaefmkkMEQSILFDVMMAANYLNI 73
Cdd:cd18321 24 TIKAMlsgpgQFAENETNEVRFPEISSHILEKVCEYFYYKVrYTNSSTEIPEFP------IPPEIALELLMAANFLDC 95