CD36 is expressed in a defined subpopulation of neurons in the olfactory epithelium

Sci Rep. 2016 May 5:6:25507. doi: 10.1038/srep25507.

Abstract

The sensory neurons in the olfactory epithelium (OSNs) are equipped with a large repertoire of olfactory receptors and the associated signal transduction machinery. In addition to the canonical OSNs, which express odorant receptors (ORs), the epithelium contains specialized subpopulations of sensory neurons that can detect specific information from environmental cues and relay it to relevant neuronal circuitries. Here we describe a subpopulation of mature OSNs in the main olfactory epithelium (MOE) which expresses CD36, a multifunctional receptor involved in a series of biological processes, including sensory perception of lipid ligands. The Cd36 expressing neurons coexpress markers of mature OSNs and are dispersed throughout the MOE. Unlike several ORs analyzed in our study, we found frequent coexpression of the OR Olfr287 in these neurons, suggesting that only a specific set of ORs may be coexpressed with CD36 in OSNs. We also show that CD36 is expressed in the cilia of OSNs, indicating a possible role in odorant detection. CD36-deficient mice display no signs of gross changes in the organization of the olfactory epithelium, but show impaired preference for a lipid mixture odor. Our results show that CD36-expressing neurons represent a distinct population of OSNs, which may have specific functions in olfaction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CD36 Antigens / deficiency
  • CD36 Antigens / genetics*
  • Cilia / drug effects
  • Cilia / metabolism
  • GTP-Binding Protein alpha Subunits / genetics*
  • GTP-Binding Protein alpha Subunits / metabolism
  • Gene Expression Regulation
  • Lipids / pharmacology
  • Male
  • Mice
  • Mice, Knockout
  • Odorants / analysis
  • Olfactory Marker Protein / genetics*
  • Olfactory Marker Protein / metabolism
  • Olfactory Mucosa / cytology
  • Olfactory Mucosa / metabolism*
  • Olfactory Receptor Neurons / cytology
  • Olfactory Receptor Neurons / drug effects
  • Olfactory Receptor Neurons / metabolism*
  • Pheromones / pharmacology
  • Protein Isoforms / genetics
  • Protein Isoforms / metabolism
  • Receptors, Odorant / genetics*
  • Receptors, Odorant / metabolism
  • Smell / physiology

Substances

  • CD36 Antigens
  • GTP-Binding Protein alpha Subunits
  • Lipids
  • Olfactory Marker Protein
  • Omp protein, mouse
  • Pheromones
  • Protein Isoforms
  • Receptors, Odorant
  • olfactory G protein subunit alpha olf