X-chromosome silencing in the germline of C. elegans

Development. 2002 Jan;129(2):479-92.


Germline maintenance in the nematode C. elegans requires global repressive mechanisms that involve chromatin organization. During meiosis, the X chromosome in both sexes exhibits a striking reduction of histone modifications that correlate with transcriptional activation when compared with the genome as a whole. The histone modification spectrum on the X chromosome corresponds with a lack of transcriptional competence, as measured by reporter transgene arrays. The X chromosome in XO males is structurally analogous to the sex body in mammals, contains a histone modification associated with heterochromatin in other species and is inactivated throughout meiosis. The synapsed X chromosomes in hermaphrodites also appear to be silenced in early meiosis, but genes on the X chromosome are detectably expressed at later stages of oocyte meiosis. Silencing of the sex chromosome during early meiosis is a conserved feature throughout the nematode phylum, and is not limited to hermaphroditic species.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Caenorhabditis elegans / cytology
  • Caenorhabditis elegans / embryology*
  • Caenorhabditis elegans / genetics*
  • Disorders of Sex Development
  • Female
  • Gene Expression Regulation, Developmental*
  • Gene Silencing*
  • Genes, Reporter
  • Germ Cells / physiology*
  • Gonads / physiology
  • Histones / metabolism*
  • Immunohistochemistry
  • In Situ Hybridization, Fluorescence
  • Male
  • Meiosis
  • Methylation
  • Oligonucleotide Array Sequence Analysis
  • Oocytes / physiology
  • Recombinant Fusion Proteins / metabolism
  • Spermatozoa / physiology
  • Transcription, Genetic
  • Transgenes
  • X Chromosome / genetics*
  • X Chromosome / metabolism


  • Histones
  • Recombinant Fusion Proteins