The G alpha protein ODR-3 mediates olfactory and nociceptive function and controls cilium morphogenesis in C. elegans olfactory neurons

Neuron. 1998 Jan;20(1):55-67. doi: 10.1016/s0896-6273(00)80434-1.


The Gi/Go-like G alpha protein ODR-3 is strongly and selectively implicated in the function of C. elegans olfactory and nociceptive neurons. Either loss of odr-3 function or overexpression of odr-3 causes severe olfactory defects, and odr-3 function is essential in the ASH neurons that sense noxious chemical and mechanical stimuli. In the nociceptive neurons, ODR-3 may interact with OSM-9, a channel similar to the mammalian capsaicin receptor implicated in pain sensation; in AWC olfactory neurons, ODR-3 may interact with another signal transduction pathway. ODR-3 exhibits an unexpected ability to regulate morphogenesis of the olfactory cilia. In odr-3 null mutants, the fan-like AWC cilia take on a filamentous morphology like normal AWA cilia, whereas ODR-3 overexpression in AWA transforms its filamentous cilia into a fan-like morphology.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Avoidance Learning / physiology
  • Base Sequence
  • Caenorhabditis elegans / physiology*
  • Caenorhabditis elegans Proteins*
  • Cilia / physiology*
  • GTP-Binding Protein alpha Subunits, Gi-Go*
  • GTP-Binding Proteins / genetics
  • GTP-Binding Proteins / metabolism
  • GTP-Binding Proteins / physiology*
  • Heterotrimeric GTP-Binding Proteins*
  • Mechanoreceptors / physiopathology
  • Molecular Sequence Data
  • Mutation
  • Neurons, Afferent / metabolism
  • Neurons, Afferent / physiology*
  • Nociceptors / physiology*
  • Nociceptors / physiopathology
  • Olfactory Pathways / cytology
  • Olfactory Pathways / physiology*
  • Sensation Disorders / genetics
  • Sensation Disorders / physiopathology
  • Smell / physiology


  • Caenorhabditis elegans Proteins
  • odr-3 protein, C elegans
  • GTP-Binding Proteins
  • GTP-Binding Protein alpha Subunits, Gi-Go
  • Heterotrimeric GTP-Binding Proteins