The sperm-oocyte switch in the C. elegans hermaphrodite is controlled through steady-state levels of the fem-3 mRNA

RNA. 2012 Jul;18(7):1385-94. doi: 10.1261/rna.031237.111. Epub 2012 May 25.

Abstract

Post-transcriptional control regulates many aspects of germline development in the Caenorhabditis elegans hermaphrodite. This nematode switches from spermatogenesis to oogenesis and is, therefore, capable of self-fertilization. This sperm-oocyte switch requires 3' UTR-mediated repression of the fem-3 mRNA. Loss of fem-3 repression results in continuous spermatogenesis in hermaphrodites. Although several factors regulating fem-3 have been identified, little is known about the mechanisms that control fem-3. Here, we investigate the steady-state levels of the fem-3 transcript and the expression pattern of its protein product. We show that FEM-3 is exclusively present in germ cells that are committed to spermatogenesis. We found that in fem-3(gf)/+ heterozygotes, mutant fem-3 gain-of-function transcripts are more abundant than their wild-type counterpart. Furthermore, we show that the penetrance of the fem-3(gf) allele correlates with inefficient FBF binding and extended poly(A) tail size of fem-3 mRNAs. Finally, we show that wild-type and gain-of-function mutated fem-3 mRNAs associate equally well with polyribosomes. We propose that the fem-3 mRNA is regulated through stabilization rather than through translatability.

Publication types

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

MeSH terms

  • Animals
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans / metabolism
  • Caenorhabditis elegans Proteins / biosynthesis
  • Caenorhabditis elegans Proteins / genetics*
  • Caenorhabditis elegans Proteins / metabolism*
  • Female
  • Gene Expression
  • Gene Expression Regulation, Developmental
  • Genes, Switch*
  • Hermaphroditic Organisms / genetics*
  • Heterozygote
  • Male
  • Oocytes / growth & development*
  • Oogenesis / genetics
  • Oogenesis / physiology
  • Protein Binding
  • RNA, Messenger / metabolism*
  • RNA-Binding Proteins / metabolism*
  • Spermatogenesis / genetics
  • Spermatogenesis / physiology
  • Spermatozoa / growth & development*

Substances

  • Caenorhabditis elegans Proteins
  • RNA, Messenger
  • RNA-Binding Proteins
  • fem-3 protein, C elegans
  • fem-3-binding protein, C elegans