Genetic and neural mechanisms that inhibit Drosophila from mating with other species

Cell. 2013 Jul 3;154(1):89-102. doi: 10.1016/j.cell.2013.06.008. Epub 2013 Jun 27.

Abstract

Genetically hard-wired neural mechanisms must enforce behavioral reproductive isolation because interspecies courtship is rare even in sexually naïve animals of most species. We find that the chemoreceptor Gr32a inhibits male D. melanogaster from courting diverse fruit fly species. Gr32a recognizes nonvolatile aversive cues present on these reproductively dead-end targets, and activity of Gr32a neurons is necessary and sufficient to inhibit interspecies courtship. Male-specific Fruitless (Fru(M)), a master regulator of courtship, also inhibits interspecies courtship. Gr32a and Fru(M) are not coexpressed, but Fru(M) neurons contact Gr32a neurons, suggesting that these genes influence a shared neural circuit that inhibits interspecies courtship. Gr32a and Fru(M) also suppress within-species intermale courtship, but we show that distinct mechanisms preclude sexual displays toward conspecific males and other species. Although this chemosensory pathway does not inhibit interspecies mating in D. melanogaster females, similar mechanisms appear to inhibit this behavior in many other male drosophilids.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Courtship
  • Drosophila / classification
  • Drosophila / genetics
  • Drosophila / physiology
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism
  • Drosophila melanogaster / genetics
  • Drosophila melanogaster / physiology*
  • Female
  • Genetic Speciation
  • Male
  • Mating Preference, Animal*
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism
  • Neurons / metabolism
  • Receptors, Cell Surface / genetics
  • Receptors, Cell Surface / metabolism
  • Transcription Factors / genetics
  • Transcription Factors / metabolism

Substances

  • Drosophila Proteins
  • Gr32a protein, Drosophila
  • Nerve Tissue Proteins
  • Receptors, Cell Surface
  • Transcription Factors
  • fru protein, Drosophila