A single SR-like protein, Npl3, promotes pre-mRNA splicing in budding yeast.
Mammalian SR proteins are a family of reversibly phosphorylated RNA binding proteins primarily studied for their roles in alternative splicing. While budding yeast lack alternative splicing, they do have three SR-like proteins: Npl3, Gbp2, and Hrb1. However, these have been best characterized for their roles in mRNA export, leaving their potential roles in splicing largely unexplored. Here, we combined high-density genetic interaction profiling and genome-wide splicing-sensitive microarray analysis to demonstrate that a single SR-like protein, Npl3, is required for efficient splicing of a large set of pre-mRNAs in Saccharomyces cerevisiae. We tested the hypothesis that Npl3 promotes splicing by facilitating cotranscriptional recruitment of splicing factors. Using chromatin immunoprecipitation, we showed that mutation of NPL3 reduces the occupancy of U1 and U2 snRNPs at genes whose splicing is stimulated by Nbl3. This result provides strong evidence that an SR protein can promote recruitment of splicing factors to chromatin.
Pubmed ID: 19061647 RIS Download
Chromatin | Gene Deletion | Nuclear Proteins | Oligonucleotide Array Sequence Analysis | Protein Binding | RNA Precursors | RNA Splicing | RNA-Binding Proteins | Ribonucleoprotein, U1 Small Nuclear | Ribonucleoprotein, U2 Small Nuclear | Saccharomyces cerevisiae | Saccharomyces cerevisiae Proteins | Serine-Arginine Splicing Factors | Spliceosomes