title: GLD-2/RNP-8 cytoplasmic poly(A) polymerase is a broad-spectrum regulator of the oogenesis program.
abstract: Regulated polyadenylation is a broadly conserved mechanism that controls key events during oogenesis. Pivotal to that mechanism is GLD-2, a catalytic subunit of cytoplasmic poly(A) polymerase (PAP). Caenorhabditis elegans GLD-2 forms an active PAP with multiple RNA-binding partners to regulate diverse aspects of germline and early embryonic development. One GLD-2 partner, RNP-8, was previously shown to influence oocyte fate specification. Here we use a genomic approach to identify transcripts selectively associated with both GLD-2 and RNP-8. Among the 335 GLD-2/RNP-8 potential targets, most were annotated as germline mRNAs and many as maternal mRNAs. These targets include gld-2 and rnp-8 themselves, suggesting autoregulation. Removal of either GLD-2 or RNP-8 resulted in shortened poly(A) tails and lowered abundance of four target mRNAs (oma-2, egg-1, pup-2, and tra-2); GLD-2 depletion also lowered the abundance of most GLD-2/RNP-8 putative target mRNAs when assayed on microarrays. Therefore, GLD-2/RNP-8 appears to polyadenylate and stabilize its target mRNAs. We also provide evidence that rnp-8 influences oocyte development; rnp-8 null mutants have more germ cell corpses and fewer oocytes than normal. Furthermore, RNP-8 appears to work synergistically with another GLD-2-binding partner, GLD-3, to ensure normal oogenesis. We propose that the GLD-2/RNP-8 enzyme is a broad-spectrum regulator of the oogenesis program that acts within an RNA regulatory network to specify and produce fully functional oocytes.
authors.affiliation: Department of Biochemistry and Howard Hughes Medical Institute, University of Wisconsin, Madison, WI 53706, USA.
authors.forename: Kyung Won
authors.initials: KW
authors.lastname: Kim
authors.forename: Tracy L
authors.initials: TL
authors.lastname: Wilson
authors.forename: Judith
authors.initials: J
authors.lastname: Kimble
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000033:anatomy & histology / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005854:Germ Cells / Q000378:metabolism; D046228:Microarray Analysis; D009865:Oocytes / Q000166:cytology / Q000502:physiology; D009866:Oogenesis / Q000502:physiology*; D011061:Poly A / Q000378:metabolism; D011062:Polynucleotide Adenylyltransferase / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D029742:Caenorhabditis elegans Proteins; D002352:Carrier Proteins; D012333:RNA, Messenger; C541033:RNP-8 protein, C elegans; D011061:Poly A; C491056:GLD-2 protein, C elegans; D011062:Polynucleotide Adenylyltransferase