Insulin signalling regulates remating in female Drosophila

Proc Biol Sci. 2011 Feb 7;278(1704):424-31. doi: 10.1098/rspb.2010.1390. Epub 2010 Aug 25.

Abstract

Mating rate is a major determinant of female lifespan and fitness, and is predicted to optimize at an intermediate level, beyond which superfluous matings are costly. In female Drosophila melanogaster, nutrition is a key regulator of mating rate but the underlying mechanism is unknown. The evolutionarily conserved insulin/insulin-like growth factor-like signalling (IIS) pathway is responsive to nutrition, and regulates development, metabolism, stress resistance, fecundity and lifespan. Here we show that inhibition of IIS, by ablation of Drosophila insulin-like peptide (DILP)-producing median neurosecretory cells, knockout of dilp2, dilp3 or dilp5 genes, expression of a dominant-negative DILP-receptor (InR) transgene or knockout of Lnk, results in reduced female remating rates. IIS-mediated regulation of female remating can occur independent of virgin receptivity, developmental defects, reduced body size or fecundity, and the receipt of the female receptivity-inhibiting male sex peptide. Our results provide a likely mechanism by which females match remating rates to the perceived nutritional environment. The findings suggest that longevity-mediating genes could often have pleiotropic effects on remating rate. However, overexpression of the IIS-regulated transcription factor dFOXO in the fat body-which extends lifespan-does not affect remating rate. Thus, long life and reduced remating are not obligatorily coupled.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Drosophila Proteins / physiology*
  • Drosophila melanogaster / physiology*
  • Female
  • Fertility / physiology*
  • Insulin / physiology*
  • Linear Models
  • Male
  • Mifepristone / pharmacology
  • Nutritional Status / physiology*
  • Signal Transduction / physiology
  • Transduction, Genetic

Substances

  • Drosophila Proteins
  • Insulin
  • Mifepristone