TATA box binding protein (TBP): Present in archaea and eukaryotes, TBPs are transcription factors that recognize promoters and initiate transcription. TBP has been shown to be an essential component of three different transcription initiation complexes: SL1, TFIID and TFIIIB, directing transcription by RNA polymerases I, II and III, respectively. TBP binds directly to the TATA box promoter element, where it nucleates polymerase assembly, thus defining the transcription start site. TBP's binding in the minor groove induces a dramatic DNA bending while its own structure barely changes. The conserved core domain of TBP, which binds to the TATA box, has a bipartite structure, with intramolecular symmetry generating a saddle-shaped structure that sits astride the DNA. New members of the TBP family, called TBP-like proteins (TBLP, TLF, TLP) or TBP-related factors (TRF1, TRF2,TRP), are similar to the core domain of TBPs, with identical or chemically similar amino acids at many equivalent positions, suggesting similar structure. However, TLFs contain distinct, conserved amino acids at several positions that distinguish them from TBP.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1331531924 159 SVLIFETGSVIVVG---LQDpsltklcVIKATTDIADILQK----NISVANVSIVNTVSTFNrfhLNF-IRLGKFFERNC 230
Cdd:cd00652    49 TALIFSSGKMVITGaksEED-------AKLAARKYARILQKlgfpVEKFPEFKVQNIVASCD---LGFpIRLEELALKHP 118

                          90       100
                  ....*....|....*....|
gi 1331531924 231 ISYSYNPETFPGMFFKLRVP 250
Cdd:cd00652   119 ENASYEPELFPGLIYRMDEP 138

TATA box binding protein (TBP): Present in archaea and eukaryotes, TBPs are transcription factors that recognize promoters and initiate transcription. TBP has been shown to be an essential component of three different transcription initiation complexes: SL1, TFIID and TFIIIB, directing transcription by RNA polymerases I, II and III, respectively. TBP binds directly to the TATA box promoter element, where it nucleates polymerase assembly, thus defining the transcription start site. TBP's binding in the minor groove induces a dramatic DNA bending while its own structure barely changes. The conserved core domain of TBP, which binds to the TATA box, has a bipartite structure, with intramolecular symmetry generating a saddle-shaped structure that sits astride the DNA. New members of the TBP family, called TBP-like proteins (TBLP, TLF, TLP) or TBP-related factors (TRF1, TRF2,TRP), are similar to the core domain of TBPs, with identical or chemically similar amino acids at many equivalent positions, suggesting similar structure. However, TLFs contain distinct, conserved amino acids at several positions that distinguish them from TBP.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1331531924 159 SVLIFETGSVIVVG---LQDpsltklcVIKATTDIADILQK----NISVANVSIVNTVSTFNrfhLNF-IRLGKFFERNC 230
Cdd:cd00652    49 TALIFSSGKMVITGaksEED-------AKLAARKYARILQKlgfpVEKFPEFKVQNIVASCD---LGFpIRLEELALKHP 118

                          90       100
                  ....*....|....*....|
gi 1331531924 231 ISYSYNPETFPGMFFKLRVP 250
Cdd:cd00652   119 ENASYEPELFPGLIYRMDEP 138

TATA box binding protein (TBP): Present in archaea and eukaryotes, TBPs are transcription factors that recognize promoters and initiate transcription. TBP has been shown to be an essential component of three different transcription initiation complexes: SL1, TFIID and TFIIIB, directing transcription by RNA polymerases I, II and III, respectively. TBP binds directly to the TATA box promoter element, where it nucleates polymerase assembly, thus defining the transcription start site. TBP's binding in the minor groove induces a dramatic DNA bending while its own structure barely changes. The conserved core domain of TBP, which binds to the TATA box, has a bipartite structure, with intramolecular symmetry generating a saddle-shaped structure that sits astride the DNA. New members of the TBP family, called TBP-like proteins (TBLP, TLF, TLP) or TBP-related factors (TRF1, TRF2,TRP), are similar to the core domain of TBPs, with identical or chemically similar amino acids at many equivalent positions, suggesting similar structure. However, TLFs contain distinct, conserved amino acids at several positions that distinguish them from TBP.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1331531924 159 SVLIFETGSVIVVG---LQDpsltklcVIKATTDIADILQK----NISVANVSIVNTVSTFNrfhLNF-IRLGKFFERNC 230
Cdd:cd00652    49 TALIFSSGKMVITGaksEED-------AKLAARKYARILQKlgfpVEKFPEFKVQNIVASCD---LGFpIRLEELALKHP 118

                          90       100
                  ....*....|....*....|
gi 1331531924 231 ISYSYNPETFPGMFFKLRVP 250
Cdd:cd00652   119 ENASYEPELFPGLIYRMDEP 138

TBP-like factors (TLF; also called TLP, TRF, TRP), which are found in most metazoans. TLFs and TBPs have well-conserved core domains; however, they only share about 60% similarity. TLFs, like TBPs, interact with TFIIA and TFIIB, which are part of the basal transcription machinery. Yet, in contrast to TBPs, TLFs seem not to interact with the TATA-box and even have a negative effect on the transcription of TATA-containing promoters. Recent results indicate that TLFs are involved in the transcription via TATA-less promoters.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1331531924 151 LKNRESFFSVLIFETGSVIVVGLQDPSLTKlcviKATTDIADILQK----NISVANVSIVNTVSTFNrfhLNF-IRLGKF 225
Cdd:cd04517    41 MRLREPRATASVWSSGKITITGATSEEEAK----QAARRAARLLQKlgfkVVRFSNFRVVNVLATCS---MPFpIRLDEL 113

                          90       100
                  ....*....|....*....|....*
gi 1331531924 226 FERNCISYSYNPETFPGMFFKLRVP 250
Cdd:cd04517   114 AAKNRSSASYEPELHPGVVYRITGP 138