title: PRP28, a 'DEAD-box' protein, is required for the first step of mRNA splicing in vitro.
abstract: We previously reported the isolation of PRP28, a gene in Saccharomyces cerevisiae whose activity is required for the first step of nuclear mRNA splicing in vivo. Sequence analysis revealed that PRP28 is included in the 'DEAD-box' gene family, members of which are thought to function as ATP-dependent RNA helicases. Genetic interactions led us to suggest that PRP28 is functionally associated with the U4/U5/U6 snRNP. We have now purified the PRP28 protein from S. cerevisiae and demonstrated that it is required for the first step of splicing in vitro. Interestingly, PRP28 is not a stably associated snRNP protein. Strand displacement assays indicate that PRP28 does not exhibit RNA helicase activity, suggesting that an additional factor or factors may be required for its activation.
authors.affiliation: Department of Biochemistry, University of California, San Francisco 94143-0448.
authors.forename: E J
authors.initials: EJ
authors.lastname: Strauss
authors.forename: C
authors.initials: C
authors.lastname: Guthrie
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000878:Anthranilate Synthase / Q000235:genetics; D000906:Antibodies / Q000494:pharmacology; D053487:DEAD-box RNA Helicases; D004926:Escherichia coli / Q000235:genetics; D012313:RNA / Q000494:pharmacology; D020365:RNA Helicases; D012316:RNA Nucleotidyltransferases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D012326:RNA Splicing; D012333:RNA, Messenger / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000276:immunology / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000737:chemistry* / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins
chemical_list: D000906:Antibodies; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D012313:RNA; D000255:Adenosine Triphosphate; D012316:RNA Nucleotidyltransferases; D000251:Adenosine Triphosphatases; C088939:PRP28 protein, S cerevisiae; D053487:DEAD-box RNA Helicases; D020365:RNA Helicases; D000878:Anthranilate Synthase