Unphosphorylated SR-like protein Npl3 stimulates RNA polymerase II elongation.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 18818768.
- Also identified by DOI 10.1371/journal.pone.0003273 and PMC identifier 2538588.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The production of a functional mRNA is regulated at every step of transcription. An area not well-understood is the transition of RNA polymerase II from elongation to termination. The S. cerevisiae SR-like protein Npl3 functions to negatively regulate transcription termination by antagonizing the binding of polyA/termination proteins to the mRNA. In this study, Npl3 is shown to interact with the CTD and have a direct stimulatory effect on the elongation activity of the polymerase. The interaction is inhibited by phosphorylation of Npl3. In addition, Casein Kinase 2 was found to be required for the phosphorylation of Npl3 and affect its ability to compete against Rna15 (Cleavage Factor I) for binding to polyA signals. Our results suggest that phosphorylation of Npl3 promotes its dissociation from the mRNA/RNAP II, and contributes to the association of the polyA/termination factor Rna15. This work defines a novel role for Npl3 in elongation and its regulation by phosphorylation.
Medical subject headings
- Nuclear Proteins
- RNA Polymerase II
- RNA-Binding Proteins
- Saccharomyces cerevisiae
- Saccharomyces cerevisiae Proteins