Inositol 1,4,5-trisphosphate signaling regulates mating behavior in Caenorhabditis elegans males

Mol Biol Cell. 2005 Sep;16(9):3978-86. doi: 10.1091/mbc.e05-02-0096. Epub 2005 Jun 15.


Complex behavior requires the coordinated action of the nervous system and nonneuronal targets. Male mating in Caenorhabditis elegans consists of a series of defined behavioral steps that lead to the physiological outcomes required for successful impregnation. We demonstrate that signaling mediated by inositol 1,4,5-trisphosphate (IP(3)) is required at several points during mating. Disruption of IP(3) receptor (itr-1) function results in dramatic loss of male fertility, due to defects in turning behavior (during vulva location), spicule insertion and sperm transfer. To elucidate the signaling pathways responsible, we knocked down the six C. elegans genes encoding phospholipase C (PLC) family members. egl-8, which encodes PLC-beta, functions in spicule insertion and sperm transfer. itr-1 and egl-8 are widely expressed in the male reproductive system. An itr-1 gain-of-function mutation rescues infertility caused by egl-8 RNA interference, indicating that egl-8 and itr-1 function together as central components of the signaling events controlling sperm transfer.

Publication types

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

MeSH terms

  • Animals
  • Antinematodal Agents / pharmacology
  • Caenorhabditis elegans / drug effects
  • Caenorhabditis elegans / physiology*
  • Calcium Channels / genetics
  • Calcium Signaling / physiology
  • Fertility / physiology
  • Inositol 1,4,5-Trisphosphate / physiology*
  • Inositol 1,4,5-Trisphosphate Receptors
  • Isoenzymes / genetics
  • Levamisole / pharmacology
  • Male
  • Mutation
  • Phospholipase C beta
  • RNA Interference
  • Receptors, Cytoplasmic and Nuclear / genetics
  • Sexual Behavior, Animal / drug effects
  • Sexual Behavior, Animal / physiology*
  • Signal Transduction / physiology*
  • Spermatogenesis / physiology
  • Spermatozoa / physiology
  • Type C Phospholipases / genetics


  • Antinematodal Agents
  • Calcium Channels
  • Inositol 1,4,5-Trisphosphate Receptors
  • Isoenzymes
  • Receptors, Cytoplasmic and Nuclear
  • Levamisole
  • Inositol 1,4,5-Trisphosphate
  • Type C Phospholipases
  • Phospholipase C beta