The terminal differentiation factor LIN-29 is required for proper vulval morphogenesis and egg laying in Caenorhabditis elegans

Development. 1997 Nov;124(21):4333-42. doi: 10.1242/dev.124.21.4333.


Caenorhabditis elegans vulval development culminates during exit from the L4-to-adult molt with the formation of an opening through the adult hypodermis and cuticle that is used for egg laying and mating. Vulva formation requires the heterochronic gene lin-29, which triggers hypodermal cell terminal differentiation during the final molt. lin-29 mutants are unable to lay eggs or mate because no vulval opening forms; instead, a protrusion forms at the site of the vulva. We demonstrate through analysis of genetic mosaics that lin-29 is absolutely required in a small subset of lateral hypodermal seam cells, adjacent to the vulva, for wild-type vulva formation and egg laying. However, lin-29 function is not strictly limited to the lateral hypodermis. First, LIN-29 accumulates in many non-hypodermal cells with known roles in vulva formation or egg laying. Second, animals homozygous for one lin-29 allele, ga94, have the vulval defect and cannot lay eggs, despite having a terminally differentiated adult lateral hypodermis. Finally, vulval morphogenesis and egg laying requires lin-29 activity within the EMS lineage, a lineage that does not generate hypodermal cells.

Publication types

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

MeSH terms

  • Animals
  • Caenorhabditis elegans / genetics*
  • Caenorhabditis elegans / growth & development*
  • Caenorhabditis elegans Proteins*
  • Cell Differentiation / genetics
  • Cell Fusion / genetics
  • Codon, Terminator
  • DNA-Binding Proteins / genetics*
  • Female
  • Larva
  • Mosaicism
  • Mutation
  • Oviposition / physiology*
  • Phenotype
  • Transcription Factors / genetics*
  • Uterus / growth & development
  • Vulva / growth & development*


  • Caenorhabditis elegans Proteins
  • Codon, Terminator
  • DNA-Binding Proteins
  • LIN-29 protein, C elegans
  • Transcription Factors