Ric-8B interacts with G alpha olf and G gamma 13 and co-localizes with G alpha olf, G beta 1 and G gamma 13 in the cilia of olfactory sensory neurons

Mol Cell Neurosci. 2008 Jul;38(3):341-8. doi: 10.1016/j.mcn.2008.03.006. Epub 2008 Apr 1.


Olfactory sensory neurons are able to detect odorants with high sensitivity and specificity. We have demonstrated that Ric-8B, a guanine nucleotide exchange factor (GEF), interacts with Galphaolf and enhances odorant receptor signaling. Here we show that Ric-8B also interacts with Ggamma13, a divergent member of the Ggamma subunit family which has been implicated in taste signal transduction, and is abundantly expressed in the cilia of olfactory sensory neurons. We show that Gbeta1 is the predominant Gbeta subunit expressed in the olfactory sensory neurons. Ric-8B and Gbeta1, like Galphaolf and Ggamma13, are enriched in the cilia of olfactory sensory neurons. We also show that Ric-8B interacts with Galphaolf in a nucleotide dependent manner, consistent with the role as a GEF. Our results constitute the first example of a GEF protein that interacts with two different olfactory G protein subunits and further implicate Ric-8B as a regulator of odorant signal transduction.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Cilia / chemistry
  • Cilia / metabolism
  • GTP-Binding Protein alpha Subunits / analysis
  • GTP-Binding Protein alpha Subunits / metabolism*
  • GTP-Binding Protein beta Subunits
  • Guanine Nucleotide Exchange Factors
  • Heterotrimeric GTP-Binding Proteins / analysis
  • Heterotrimeric GTP-Binding Proteins / metabolism*
  • Humans
  • Mice
  • Mice, Inbred C57BL
  • Nuclear Proteins / analysis
  • Nuclear Proteins / metabolism*
  • Olfactory Pathways / chemistry
  • Olfactory Pathways / metabolism
  • Olfactory Receptor Neurons / chemistry
  • Olfactory Receptor Neurons / metabolism*
  • Protein Binding / physiology
  • Sensory Receptor Cells / chemistry
  • Sensory Receptor Cells / metabolism
  • Signal Transduction / physiology


  • GTP-Binding Protein alpha Subunits
  • GTP-Binding Protein beta Subunits
  • Ggamma13 protein, mouse
  • Gnb1 protein, mouse
  • Guanine Nucleotide Exchange Factors
  • Nuclear Proteins
  • Ric8a protein, mouse
  • Ric8b protein, mouse
  • olfactory G protein subunit alpha olf
  • Heterotrimeric GTP-Binding Proteins