title: Isolation and expression of cDNA clones encoding mammalian poly(A) polymerase.
abstract: cDNA clones encoding mammalian poly(A) polymerase were isolated with probes generated by the polymerase chain reaction based on amino acid sequences derived from the purified enzyme. A bovine cDNA clone was obtained encoding a protein of 82 kDa. Expression in Escherichia coli resulted in the appearance of a poly(A) polymerase activity that was dependent on the addition of the purified specificity factor CPF and the presence of the polyadenylation signal AAUAAA in the RNA substrate. The activity copurified with a polypeptide of the expected size. A second class of cDNAs encoded a polypeptide of 43 kDa which was closely related to the N-terminal half of the 82 kDa protein. Northern blots showed two mRNAs of 4.2 and 2.4 kb that probably correspond to the two classes of cDNAs, as well as a third band of 1.3 kb. The sequence of the N-terminal half of bovine poly(A) polymerase is 47% identical with the amino acid sequence of the corresponding part of yeast poly(A) polymerase. Homologies to other proteins are of uncertain significance.
authors.affiliation: Universität Basel, Abteilung Zellbiologie, Switzerland.
authors.forename: E
authors.initials: E
authors.lastname: Wahle
authors.forename: G
authors.initials: G
authors.lastname: Martin
authors.forename: E
authors.initials: E
authors.lastname: Schiltz
authors.forename: W
authors.initials: W
authors.lastname: Keller
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002417:Cattle; D002853:Chromatography, Liquid; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics* / Q000302:isolation & purification; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D005798:Genes, Bacterial; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D010957:Plasmids; D016133:Polymerase Chain Reaction; D011062:Polynucleotide Adenylyltransferase / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D004247:DNA; D011062:Polynucleotide Adenylyltransferase