Phosphorylated RNA polymerase II stimulates pre-mRNA splicing.
RNA polymerase II (RNAP II) is responsible for transcription of mRNA precursors in eukaryotic cells. Recent studies, however, have suggested that RNAP II also participates in subsequent RNA processing reactions through interactions between the carboxy-terminal domain (CTD) of the RNAP II largest subunit and processing factors. Using reconstituted in vitro splicing assays, we show that RNAP II functions directly in pre-mRNA splicing by influencing very early steps in assembly of the spliceosome. We demonstrate that the phosphorylation status of the CTD dramatically affects activity: Hyperphosphorylated RNAP IIO strongly activates splicing, whereas hypophosphorylated RNAP IIA can inhibit the reaction.
Hirose
Y
Y
Department of Biological Sciences, Columbia University, New York, New York, 10027 USA.
Tacke
R
R
Manley
J L
JL
D002467:Cell Nucleus / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005914:Globins / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D010766:Phosphorylation; D012319:RNA Polymerase II / Q000502:physiology*; D012322:RNA Precursors / Q000378:metabolism*; D012326:RNA Splicing / Q000502:physiology*; D009418:S100 Proteins / Q000378:metabolism; D017381:Spliceosomes / Q000378:metabolism; D013997:Time Factors
D012322:RNA Precursors; D009418:S100 Proteins; D005914:Globins; D012319:RNA Polymerase II