The Rpb4 subunit of RNA polymerase II contributes to cotranscriptional recruitment of 3' processing factors.
The RNA polymerase II enzyme from the yeast Saccharomyces cerevisiae is a complex of 12 subunits, Rpb1 to Rpb12. Crystal structures of the full complex show that the polymerase consists of two separable components, a 10-subunit core including the catalytic active site and a heterodimer of the Rpb4 and Rpb7 subunits. To characterize the role of the Rpb4/7 heterodimer during transcription in vivo, chromatin immunoprecipitation was used to examine an rpb4Delta strain for effects on the behavior of the core polymerase as well as recruitment of other protein factors involved in transcription. Rpb4/7 cross-links throughout transcribed regions. Loss of Rpb4 results in a reduction of RNA polymerase II levels near 3' ends of multiple mRNA genes as well as a decreased association of 3'-end processing factors. Furthermore, loss of Rpb4 results in altered polyadenylation site usage at the RNA14 gene. Together, these results indicate that Rpb4 contributes to proper cotranscriptional 3'-end processing in vivo.
Runner
Vanessa M
VM
Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
Podolny
Vladimir
V
Buratowski
Stephen
S
D047369:Chromatin Immunoprecipitation; D019281:Dimerization; D015966:Gene Expression Regulation, Fungal; D025941:Protein Interaction Mapping; D026721:RNA 3' End Processing / Q000502:physiology*; D012319:RNA Polymerase II / Q000502:physiology*; D012331:RNA, Fungal / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000502:physiology*; D013329:Structure-Activity Relationship; D014157:Transcription Factors / Q000502:physiology*; D014158:Transcription, Genetic; D039221:mRNA Cleavage and Polyadenylation Factors / Q000502:physiology
D012331:RNA, Fungal; D012333:RNA, Messenger; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D039221:mRNA Cleavage and Polyadenylation Factors; C512638:RNA14 protein, S cerevisiae; D012319:RNA Polymerase II; C423309:RPB4 protein, S cerevisiae; C470553:RPB7 protein, S cerevisiae