GLD-2/RNP-8 cytoplasmic poly(A) polymerase is a broad-spectrum regulator of the oogenesis program

Proc Natl Acad Sci U S A. 2010 Oct 5;107(40):17445-50. doi: 10.1073/pnas.1012611107. Epub 2010 Sep 20.

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.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Caenorhabditis elegans / anatomy & histology
  • Caenorhabditis elegans / physiology*
  • Caenorhabditis elegans Proteins / genetics
  • Caenorhabditis elegans Proteins / metabolism*
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Female
  • Germ Cells / metabolism
  • Microarray Analysis
  • Oocytes / cytology
  • Oocytes / physiology
  • Oogenesis / physiology*
  • Poly A / metabolism
  • Polynucleotide Adenylyltransferase / genetics
  • Polynucleotide Adenylyltransferase / metabolism*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism

Substances

  • Caenorhabditis elegans Proteins
  • Carrier Proteins
  • RNA, Messenger
  • RNP-8 protein, C elegans
  • Poly A
  • GLD-2 protein, C elegans
  • Polynucleotide Adenylyltransferase

Associated data

  • GEO/GSE23843