RPL30 regulation of splicing reveals distinct roles for Cbp80 in U1 and U2 snRNP cotranscriptional recruitment.
Pre-mRNA splicing is catalyzed by the spliceosome, and its control is essential for correct gene expression. While splicing repressors typically interfere with transcript recognition by spliceosomal components, the yeast protein L30 blocks spliceosomal rearrangements required for the engagement of U2 snRNP (small ribonucleoprotein particle) to its own transcript RPL30. Using a mutation in the RPL30 binding site that disrupts this repression, we have taken a genetic approach to reveal that regulation of splicing is restored in this mutant by deletion of the cap-binding complex (CBC) component Cbp80. Indeed, our data indicate that Cbp80 plays distinct roles in the recognition of the intron by U1 and U2 snRNP. It promotes the initial 5' splice site recognition by U1 and, independently, facilitates U2 recruitment, depending on sequences located in the vicinity of the 5' splice site. These results reveal a novel function for CBC in splicing and imply that these molecular events can be the target of a splicing regulator.
Pubmed ID: 20801768 RIS Download
Amino Acid Sequence | Base Sequence | DNA Primers | Exons | Gene Deletion | Genes, Fungal | Models, Biological | Molecular Sequence Data | Mutation | Nuclear Proteins | Nucleic Acid Conformation | RNA Cap-Binding Proteins | RNA Precursors | RNA Splice Sites | RNA Splicing | RNA, Fungal | Ribonucleoprotein, U1 Small Nuclear | Ribonucleoprotein, U2 Small Nuclear | Ribosomal Proteins | Saccharomyces cerevisiae | Saccharomyces cerevisiae Proteins | Sequence Homology, Amino Acid | Spliceosomes