title: Mammalian GLD-2 homologs are poly(A) polymerases.
abstract: GLD-2 is a cytoplasmic poly(A) polymerase present in the Caenorhabditis elegans germ line and embryo. It is a divergent member of the DNA polymerase beta nucleotidyl transferase superfamily, which includes CCA-adding enzymes, DNA polymerases and eukaryotic nuclear poly(A) polymerases. The polyadenylation activity of GLD-2 is stimulated by physical interaction with an RNA binding protein, GLD-3. To test whether GLD-3 might stimulate GLD-2 by recruiting it to RNA, we tethered C. elegans GLD-2 to mRNAs in Xenopus oocytes by using MS2 coat protein. Tethered GLD-2 adds poly(A) and stimulates translation of the mRNA, demonstrating that recruitment is sufficient to stimulate polyadenylation activity. We use the same tethered assay to identify human and mouse poly(A) polymerases related to GLD-2. This may provide entrees to previously uncharacterized modes of polyadenylation in mammalian cells.
authors.affiliation: Department of Biochemistry, 433 Babcock Drive, University of Wisconsin, Madison, WI 53706-1544, USA.
authors.forename: Jae Eun
authors.initials: JE
authors.lastname: Kwak
authors.forename: Liaoteng
authors.initials: L
authors.lastname: Wang
authors.forename: Scott
authors.initials: S
authors.lastname: Ballantyne
authors.forename: Judith
authors.initials: J
authors.lastname: Kimble
authors.forename: Marvin
authors.initials: M
authors.lastname: Wickens
mesh_terms: D000818:Animals; D006801:Humans; D007700:Kinetics; D051379:Mice; D008958:Models, Molecular; D009713:Nucleotidyltransferases / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D010957:Plasmids; D011061:Poly A / Q000378:metabolism; D011062:Polynucleotide Adenylyltransferase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D014176:Protein Biosynthesis; D011487:Protein Conformation; D012333:RNA, Messenger / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D011061:Poly A; D009713:Nucleotidyltransferases; D011062:Polynucleotide Adenylyltransferase