Promotion of oogenesis and embryogenesis in the C. elegans gonad by EFL-1/DPL-1 (E2F) does not require LIN-35 (pRB)

Development. 2006 Aug;133(16):3147-57. doi: 10.1242/dev.02490. Epub 2006 Jul 19.

Abstract

In Caenorhabditis elegans, EFL-1 (E2F), DPL-1 (DP) and LIN-35 (pRb) act coordinately in somatic tissues to inhibit ectopic cell division, probably by repressing the expression of target genes. EFL-1, DPL-1 and LIN-35 are also present in the germline, but do not always act together. Strong loss-of-function mutations in either efl-1 or dpl-1 cause defects in oogenesis that result in sterility, while lin-35 mutants are fertile with reduced broods. Microarray-based expression profiling of dissected gonads from efl-1, dpl-1 and lin-35 mutants reveals that EFL-1 and DPL-1 promote expression of an extensively overlapping set of target genes, consistent with the expectation that these two proteins function as a heterodimer. Regulatory regions upstream of many of these target genes have a canonical E2F-binding site, suggesting that their regulation by EFL-1/DPL-1 is direct. Many EFL-1/DPL-1 responsive genes encode proteins required for oogenesis and early embryogenesis, rather than cell cycle components. By contrast, LIN-35 appears to function primarily as a repressor of gene expression in the germline, and the genes that it acts on are for the most part distinct from those regulated by EFL-1 and/or DPL-1. Thus, in vivo, C. elegans E2F directly promotes oogenesis and embryogenesis through the activation of a tissue-specific transcriptional program that does not require LIN-35.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Binding Sites
  • Caenorhabditis elegans / embryology*
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans / growth & development*
  • Caenorhabditis elegans Proteins / genetics
  • Caenorhabditis elegans Proteins / metabolism
  • Caenorhabditis elegans Proteins / physiology*
  • E2F Transcription Factors / genetics
  • E2F Transcription Factors / metabolism
  • E2F Transcription Factors / physiology*
  • Embryonic Development / genetics
  • Fertility / genetics
  • Gene Expression Regulation, Developmental*
  • Gonads / embryology
  • Gonads / metabolism
  • Oligonucleotide Array Sequence Analysis
  • Oogenesis / genetics*
  • RNA-Binding Proteins / genetics
  • Receptors, LDL / genetics
  • Repressor Proteins / genetics
  • Repressor Proteins / physiology
  • Transcription Factors / genetics
  • Transcription Factors / metabolism
  • Transcription Factors / physiology*
  • Transcriptional Activation

Substances

  • Caenorhabditis elegans Proteins
  • E2F Transcription Factors
  • MEX-3 protein, C elegans
  • RME-2 protein, C elegans
  • RNA-Binding Proteins
  • Receptors, LDL
  • Repressor Proteins
  • Transcription Factors
  • dpl-1 protein, C elegans
  • efl-1 protein, C elegans
  • lin-35 protein, C elegans