Stimulation of RNA polymerase II transcript cleavage activity contributes to maintain transcriptional fidelity in yeast.
The transcription elongation factor S-II, also designated TFIIS, stimulates the nascent transcript cleavage activity intrinsic to RNA polymerase II. Rpb9, a small subunit of RNA polymerase II, enhances the cleavage stimulation activity of S-II. Here, we investigated the role of nascent transcript cleavage stimulation activity on the maintenance of transcriptional fidelity in yeast. In yeast, S-II is encoded by the DST1 gene. Disruption of the DST1 gene decreased transcriptional fidelity in cells. Mutations in the DST1 gene that reduce the S-II cleavage stimulation activity led to decreased transcriptional fidelity in cells. A disruption mutant of the RPB9 gene also had decreased transcriptional fidelity. Expression of mutant Rpb9 proteins that are unable to enhance the S-II cleavage stimulation activity failed to restore the phenotype. These results suggest that both S-II and Rpb9 maintain transcriptional fidelity by stimulating the cleavage activity intrinsic to RNA polymerase II. Also, a DST1 and RPB9 double mutant had more severe transcriptional fidelity defect compared with the DST1 gene deletion mutant, suggesting that Rpb9 maintains transcriptional fidelity via two mechanisms, enhancement of S-II dependent cleavage stimulation and S-II independent function(s).
Koyama
Hiroshi
H
Department of Microbiology, Graduate School of Pharmaceutical Sciences, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Ito
Takahiro
T
Nakanishi
Toshiyuki
T
Sekimizu
Kazuhisa
K
D001483:Base Sequence; D004271:DNA, Fungal / Q000235:genetics; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D025141:Drug Resistance, Fungal / Q000235:genetics; D005800:Genes, Fungal; D017930:Genes, Reporter; D007763:Lac Operon; D008958:Models, Molecular; D009154:Mutation; D018384:Oxidative Stress; D021122:Protein Subunits; D012319:RNA Polymerase II / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D035602:Transcriptional Elongation Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D024483:Vitamin K 3 / Q000494:pharmacology
D004271:DNA, Fungal; D004268:DNA-Binding Proteins; C068394:DST1 protein, S cerevisiae; D021122:Protein Subunits; D029701:Saccharomyces cerevisiae Proteins; D035602:Transcriptional Elongation Factors; C018648:transcription factor S-II; D024483:Vitamin K 3; D012319:RNA Polymerase II; C509257:Rpb9 protein, S cerevisiae