Antagonism between GLD-2 binding partners controls gamete sex

Dev Cell. 2009 May;16(5):723-33. doi: 10.1016/j.devcel.2009.04.002.

Abstract

Cytoplasmic polyadenylation is a key mechanism of gene control. In Caenorhabditis elegans, GLD-2 and GLD-3 provide the catalytic and RNA-binding subunits, respectively, of a major cytoplasmic poly(A) polymerase (PAP). Here, we identify RNP-8 as a second GLD-2 partner. RNP-8 binds GLD-2 and stimulates GLD-2 activity to form a functional PAP, much like GLD-3. Moreover, GLD-2/RNP-8 and GLD-2/GLD-3 exist as separate complexes that form selectively during development, and RNP-8 and GLD-3 appear to have distinct RNA-binding specificities. Therefore, GLD-2 can form either of two discrete PAPs. In C. elegans hermaphrodites, gamete production begins with spermatogenesis and transitions later to oogenesis. We suggest that the combinatorial use of GLD-2 contributes to this transition, as GLD-2/GLD-3 promotes spermatogenesis, whereas GLD-2/RNP-8 specifies oogenesis. Indeed, RNP-8 and GLD-3 antagonize each other, as evidenced by genetic cosuppression and molecular competition for GLD-2 binding. We conclude that GLD-2 and its binding partners control gamete identity.

Publication types

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

MeSH terms

  • Animals
  • Caenorhabditis elegans / physiology*
  • Caenorhabditis elegans Proteins / metabolism*
  • Carrier Proteins / metabolism*
  • Disorders of Sex Development
  • Gametogenesis
  • Polynucleotide Adenylyltransferase / metabolism*
  • RNA-Binding Proteins / metabolism*

Substances

  • Caenorhabditis elegans Proteins
  • Carrier Proteins
  • GLD-3 protein, C elegans
  • RNA-Binding Proteins
  • RNP-8 protein, C elegans
  • GLD-2 protein, C elegans
  • Polynucleotide Adenylyltransferase