title: Essential yeast protein with unexpected similarity to subunits of mammalian cleavage and polyadenylation specificity factor (CPSF).
abstract: The 3' ends of most eukaryotic messenger RNAs are generated by internal cleavage and polyadenylation. In mammals, there is a strict dependence of both reactions on the sequence AAUAAA, which occurs upstream of polyadenylation [poly(A)] sites and which is recognized by CPSF. In contrast, cis-acting signals for yeast 3'-end generation are highly divergent from those of mammals, suggesting that trans-acting factors other than poly(A) polymerase would not be conserved. The essential yeast protein Brr5/Ysh1 shows sequence similarity to subunits of mammalian CPSF and is required for 3'-end processing in vivo and in vitro. These results demonstrate a structural and functional conservation of the yeast and mammalian 3'-end processing machineries despite a lack of conservation of the cis sequences.
authors.affiliation: Department of Biochemistry and Biophysics, UCSF School of Medicine, San Francisco, CA 94143-0448. guthrie@cgl.ucsf.edu.
authors.forename: G
authors.initials: G
authors.lastname: Chanfreau
authors.forename: S M
authors.initials: SM
authors.lastname: Noble
authors.forename: C
authors.initials: C
authors.lastname: Guthrie
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D017124:Conserved Sequence; D018360:Crystallography, X-Ray; D005656:Fungal Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D011061:Poly A / Q000378:metabolism; D012322:RNA Precursors / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional; D012331:RNA, Fungal / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000737:chemistry* / Q000235:genetics; D039221:mRNA Cleavage and Polyadenylation Factors
chemical_list: D005656:Fungal Proteins; D012322:RNA Precursors; D012331:RNA, Fungal; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D039221:mRNA Cleavage and Polyadenylation Factors; D011061:Poly A