title: Evidence for a mediator cycle at the initiation of transcription.
abstract: Free and elongating (DNA-bound) forms of RNA polymerase II were separated from yeast. Most cellular polymerase II was found in the elongating fraction, which contained all enzyme phosphorylated on the C-terminal domain and none of the 15-subunit mediator of transcriptional regulation. These and other findings suggest that mediator enters and leaves initiation complexes during every round of transcription, in a process that may be coupled to C-terminal domain phosphorylation.
authors.affiliation: Department of Structural Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.
authors.forename: J Q
authors.initials: JQ
authors.lastname: Svejstrup
authors.forename: Y
authors.initials: Y
authors.lastname: Li
authors.forename: J
authors.initials: J
authors.lastname: Fellows
authors.forename: A
authors.initials: A
authors.lastname: Gnatt
authors.forename: S
authors.initials: S
authors.lastname: Bjorklund
authors.forename: R D
authors.initials: RD
authors.lastname: Kornberg
mesh_terms: D015966:Gene Expression Regulation, Fungal; D007700:Kinetics; D046911:Macromolecular Substances; D008954:Models, Biological; D012319:RNA Polymerase II / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D013379:Substrate Specificity; D014157:Transcription Factors / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D035165:Transcription Factors, General; D019473:Transcription Factors, TFII; D014158:Transcription, Genetic; D035602:Transcriptional Elongation Factors
chemical_list: D046911:Macromolecular Substances; D014157:Transcription Factors; D035165:Transcription Factors, General; D019473:Transcription Factors, TFII; D035602:Transcriptional Elongation Factors; C018648:transcription factor S-II; D012319:RNA Polymerase II; C056604:transcription factor TFIIF