title: Cryptic DNA-binding domain in the C terminus of RNA polymerase II general transcription factor RAP30.
abstract: The C terminus of mammalian transcription factor RAP30 has been found to be a cryptic DNA-binding domain strikingly similar to the C-terminal DNA-binding domain present in conserved region 4 of members of the sigma 70 family of bacterial sigma factors. This RAP30 domain shares strongest sequence similarity with the DNA-binding domain present in region 4 of Bacillus subtilis sporulation-specific sigma K. Like the region 4 DNA-binding activity of Escherichia coli sigma 70, the RAP30 C-terminal DNA binding activity is masked in intact RAP30 but is readily detectable when the RAP30 C terminus is expressed as a fusion protein. Consistent with a role for RAP30 DNA-binding activity in transcription, mutations that abolish DNA binding also abolish transcription. Therefore, RAP30 may function at least in part through the action of an evolutionarily ancient DNA-binding domain that first appeared prior to the divergence of bacteria and eukaryotes.
authors.affiliation: Program in Molecular and Cell Biology, Oklahoma Medical Research Foundation, Oklahoma City 73104.
authors.forename: S
authors.initials: S
authors.lastname: Tan
authors.forename: K P
authors.initials: KP
authors.lastname: Garrett
authors.forename: R C
authors.initials: RC
authors.lastname: Conaway
authors.forename: J W
authors.initials: JW
authors.lastname: Conaway
mesh_terms: D018528:ATP-Binding Cassette Transporters; D000595:Amino Acid Sequence; D000818:Animals; D001412:Bacillus subtilis / Q000378:metabolism; D001483:Base Sequence; D001665:Binding Sites; D002352:Carrier Proteins / Q000096:biosynthesis / Q000378:metabolism; D003001:Cloning, Molecular; D004247:DNA / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism; D029968:Escherichia coli Proteins; D058619:Maltose-Binding Proteins; D008322:Mammals; D008969:Molecular Sequence Data; D009004:Monosaccharide Transport Proteins; D009838:Oligodeoxyribonucleotides / Q000378:metabolism*; D012319:RNA Polymerase II / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000302:isolation & purification / Q000378:metabolism; D012808:Sigma Factor / Q000378:metabolism; D014157:Transcription Factors / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D019473:Transcription Factors, TFII; D014158:Transcription, Genetic
chemical_list: D018528:ATP-Binding Cassette Transporters; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D058619:Maltose-Binding Proteins; D009004:Monosaccharide Transport Proteins; D009838:Oligodeoxyribonucleotides; D011993:Recombinant Fusion Proteins; D012808:Sigma Factor; D014157:Transcription Factors; D019473:Transcription Factors, TFII; C461599:maltose transport system, E coli; D004247:DNA; D012319:RNA Polymerase II; C056604:transcription factor TFIIF