A multisubunit 3' end processing factor from yeast containing poly(A) polymerase and homologues of the subunits of mammalian cleavage and polyadenylation specificity factor.
Polyadenylation is the second step in 3' end formation of most eukaryotic mRNAs. In Saccharomyces cerevisiae, this step requires three trans-acting factors: poly(A) polymerase (Pap1p), cleavage factor I (CF I) and polyadenylation factor I (PF I). Here, we describe the purification and subunit composition of a multiprotein complex containing Pap1p and PF I activities. PF I-Pap1p was purified to homogeneity by complementation of extracts mutant in the Fip1p subunit of PF I. In addition to Fip1p and Pap1p, the factor comprises homologues of all four subunits of mammalian cleavage and polyadenylation specificity factor (CPSF), as well as Ptalp, which previously has been implicated in pre-tRNA processing, and several as yet uncharacterized proteins. As expected for a PF I subunit, pta1-1 mutant extracts are deficient for polyadenylation in vitro. PF I also appears to be functionally related to CPSF, as it polyadenylates a substrate RNA more efficiently than Pap1p alone. Possibly, the observed interaction of the complex with RNA tethers Pap1p to its substrate.
Preker
P J
PJ
Department of Cell Biology, Biozentrum, University of Basel, Switzerland.
Ohnacker
M
M
Minvielle-Sebastia
L
L
Keller
W
W
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D017931:DNA Primers / Q000235:genetics; D019143:Evolution, Molecular; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D005800:Genes, Fungal; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D046912:Multiprotein Complexes; D009154:Mutation; D011062:Polynucleotide Adenylyltransferase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011487:Protein Conformation; D012323:RNA Processing, Post-Transcriptional; D012331:RNA, Fungal / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000096:biosynthesis*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D013379:Substrate Specificity; D039221:mRNA Cleavage and Polyadenylation Factors
D017931:DNA Primers; D005656:Fungal Proteins; D046911:Macromolecular Substances; D046912:Multiprotein Complexes; C076229:PTA1 protein, S cerevisiae; D012331:RNA, Fungal; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins; D039221:mRNA Cleavage and Polyadenylation Factors; D011062:Polynucleotide Adenylyltransferase