title: A yeast cap binding protein complex (yCBC) acts at an early step in pre-mRNA splicing.
abstract: The function in splicing of a heterodimeric nuclear cap binding complex (yCBC) from the yeast Saccharomyces cerevisiae has been examined. Immunodepletion of splicing extracts with antibodies directed against one component of the complex, yCBP80, results in the efficient co-depletion of the second component, yCBP20, producing CBC-deficient splicing extract. This extract exhibits strongly reduced splicing efficiency and similar reductions in the assembly of both spliceosomes and of the earliest defined precursors to spliceosomes, commitment complexes. The addition of highly purified yCBC substantially restores these defects. These results, together with other data, suggest that CBCs play a highly conserved role in the recognition of pre-mRNA substrates at an early step in the splicing process.
authors.affiliation: European Molecular Biology Laboratory, Heidelberg, Germany.
authors.forename: J D
authors.initials: JD
authors.lastname: Lewis
authors.forename: D
authors.initials: D
authors.lastname: Görlich
authors.forename: I W
authors.initials: IW
authors.lastname: Mattaj
mesh_terms: D000595:Amino Acid Sequence; D017124:Conserved Sequence; D039502:Nuclear Cap-Binding Protein Complex; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D039381:RNA Cap-Binding Proteins; D012322:RNA Precursors / Q000378:metabolism*; D012326:RNA Splicing; D012331:RNA, Fungal / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D017381:Spliceosomes / Q000378:metabolism
chemical_list: C100383:CBC2 protein, S cerevisiae; D039502:Nuclear Cap-Binding Protein Complex; D010750:Phosphoproteins; D039381:RNA Cap-Binding Proteins; D012322:RNA Precursors; D012331:RNA, Fungal; D016601:RNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins