Identification of ligands for DAF-12 that govern dauer formation and reproduction in C. elegans

Cell. 2006 Mar 24;124(6):1209-23. doi: 10.1016/j.cell.2006.01.037. Epub 2006 Mar 9.

Abstract

In response to environmental and dietary cues, the C. elegans orphan nuclear receptor, DAF-12, regulates dauer diapause, reproductive development, fat metabolism, and life span. Despite strong evidence for hormonal control, the identification of the DAF-12 ligand has remained elusive. In this work, we identified two distinct 3-keto-cholestenoic acid metabolites of DAF-9, a cytochrome P450 involved in hormone production, that function as ligands for DAF-12. At nanomolar concentrations, these steroidal ligands (called dafachronic acids) bind and transactivate DAF-12 and rescue the hormone deficiency of daf-9 mutants. Interestingly, DAF-9 has a biochemical activity similar to mammalian CYP27A1 catalyzing addition of a terminal acid to the side chain of sterol metabolites. Together, these results define the first steroid hormones in nematodes as ligands for an invertebrate orphan nuclear receptor and demonstrate that steroidal regulation of reproduction, from biology to molecular mechanism, is conserved from worms to humans.

Publication types

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

MeSH terms

  • Animals
  • Caenorhabditis elegans / metabolism*
  • Caenorhabditis elegans Proteins / agonists*
  • Caenorhabditis elegans Proteins / drug effects
  • Caenorhabditis elegans Proteins / metabolism*
  • Cholestenones / metabolism
  • Cytochrome P-450 Enzyme System / drug effects
  • Cytochrome P-450 Enzyme System / metabolism
  • Humans
  • Ketosteroids / pharmacology*
  • Ligands
  • Receptors, Cytoplasmic and Nuclear / agonists*
  • Receptors, Cytoplasmic and Nuclear / drug effects
  • Receptors, Cytoplasmic and Nuclear / metabolism*
  • Reproduction

Substances

  • Caenorhabditis elegans Proteins
  • Cholestenones
  • DAF-12 protein, C elegans
  • Ketosteroids
  • Ligands
  • Receptors, Cytoplasmic and Nuclear
  • cholest-4-en-3-one
  • Cytochrome P-450 Enzyme System
  • DAF-9 protein, C elegans