title: Cross-intron bridging interactions in the yeast commitment complex are conserved in mammals.
abstract: The commitment complex is the first defined step in the yeast (S. cerevisiae) splicing pathway. It contains U1 snRNP as well as Mud2p, which resembles human U2AF65. In a genetic screen, we identified the yeast gene MSL-5, which is a novel commitment complex component. Genetic and biochemical criteria indicate a direct interaction between Msl5p and both Mud2p and the U1 snRNP protein Prp40p. This defines a bridge between the two ends of the intron. Msl5p (renamed BBP for branchpoint bridging protein) has a mammalian ortholog, the splicing factor SF1. Our results show that SF1 interacts strongly with human U2AF65, and that SF1 is a bona fide E complex component. This implies that aspects of these novel cross-intron protein-protein interactions are conserved between yeast and mammals.
authors.affiliation: Howard Hughes Medical Institute, Department of Biology, Brandeis University, Waltham, Massachusetts 02254, USA.
authors.forename: N
authors.initials: N
authors.lastname: Abovich
authors.forename: M
authors.initials: M
authors.lastname: Rosbash
mesh_terms: D000818:Animals; D001483:Base Sequence; D017124:Conserved Sequence; D004268:DNA-Binding Proteins; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007438:Introns / Q000235:genetics*; D008322:Mammals; D016296:Mutagenesis / Q000502:physiology; D012326:RNA Splicing / Q000235:genetics; D000072260:RNA Splicing Factors; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D017412:Ribonucleoprotein, U1 Small Nuclear / Q000235:genetics / Q000378:metabolism; D012261:Ribonucleoproteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D000072668:Splicing Factor U2AF; D014157:Transcription Factors
chemical_list: D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C089980:MUD2 protein, S cerevisiae; D000072260:RNA Splicing Factors; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins; D017412:Ribonucleoprotein, U1 Small Nuclear; D012261:Ribonucleoproteins; C491516:SF1 protein, S cerevisiae; C107467:SF1 protein, human; D029701:Saccharomyces cerevisiae Proteins; D000072668:Splicing Factor U2AF; D014157:Transcription Factors