The timing of lin-4 RNA accumulation controls the timing of postembryonic developmental events in Caenorhabditis elegans

Dev Biol. 1999 Jun 1;210(1):87-95. doi: 10.1006/dbio.1999.9272.


The lin-4 gene encodes a small RNA that is required to translationally repress lin-14 toward the end of the first larval stage of Caenorhabditis elegans development. To determine if the timing of LIN-14 protein down-regulation depends on the temporal profile of lin-4 RNA level, we analyzed the stage-specificity of lin-4 RNA expression during wild-type development and examined the phenotypes of transgenic worms that overexpress lin-4 RNA during the first larval stage. We found that lin-4 RNA first becomes detectable at approximately 12 h of wild-type larval development and rapidly accumulates to nearly maximum levels by 16 h. This profile of lin-4 RNA accumulation corresponded to the timing of LIN-14 protein down-regulation. Transgenic strains that express elevated levels of lin-4 RNA prior to 12 h of development display reduced levels of LIN-14 protein and precocious phenotypes consistent with abnormally early loss of lin-14 activity. These results indicate that the temporal profile of lin-4 RNA accumulation specifies the timing of LIN-14 down-regulation and thereby controls the timing of postembryonic developmental events.

Publication types

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

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Caenorhabditis elegans / embryology*
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans Proteins*
  • Down-Regulation
  • Gene Expression Regulation, Developmental
  • Genes, Helminth
  • Helminth Proteins / genetics
  • Helminth Proteins / metabolism*
  • Immunohistochemistry
  • Nuclear Proteins*
  • Phenotype
  • Protein Biosynthesis
  • RNA, Helminth / genetics*
  • RNA, Helminth / metabolism
  • RNA, Messenger / analysis


  • Caenorhabditis elegans Proteins
  • Helminth Proteins
  • LIN-14 protein, C elegans
  • Nuclear Proteins
  • RNA, Helminth
  • RNA, Messenger