Related Experiment Video

Updated: May 12, 2026

Whole Mount Labeling of Cilia in the Main Olfactory System of Mice
08:42

Whole Mount Labeling of Cilia in the Main Olfactory System of Mice

Published on: December 27, 2014

Odorant receptor localization to olfactory cilia is mediated by ODR-4, a novel membrane-associated protein

N D Dwyer1, E R Troemel, P Sengupta

  • 1Howard Hughes Medical Institute, Department of Anatomy, The University of California, San Francisco 94143-0452, USA.

Cell
|May 20, 1998
PubMed

Insights

The C. elegans genes odr-4 and odr-8 are crucial for directing specific seven transmembrane domain odorant receptors to olfactory neuron cilia. This pathway is distinct from the localization mechanisms of other cilia-signaling proteins.

Area of Science:

  • Neuroscience
  • Molecular Biology
  • Cell Biology

Background:

  • Seven transmembrane domain receptors (7TMRs) exhibit diverse localization patterns within cells.
  • Understanding the mechanisms governing receptor trafficking is essential for cellular signaling.
  • Olfactory neurons rely on precise protein localization for chemosensation.

Purpose of the Study:

  • To identify genes involved in the ciliary localization of seven transmembrane domain odorant receptors (7TMRs) in C. elegans.
  • To elucidate the specific roles of ODR-4 and ODR-8 in protein trafficking.
  • To differentiate the localization pathways for various ciliary proteins.

Main Methods:

  • Genetic screening in C. elegans to identify mutants with mislocalized odorant receptors.
  • Analysis of gene expression patterns for odr-4 and odr-8.
  • Cell-autonomous assays to determine the function of ODR-4.

Main Results:

  • The C. elegans genes odr-4 and odr-8 are essential for the ciliary localization of a subset of 7TMR odorant receptors.
  • Localization of other ciliary proteins, including ion channels and G alpha proteins, occurs independently of ODR-4 and ODR-8.
  • ODR-4 encodes a novel membrane protein found on intracellular membranes of chemosensory neurons.

Conclusions:

  • ODR-4 and ODR-8 define a specific pathway for odorant receptor ciliary targeting.
  • ODR-4 acts cell-autonomously to promote odorant receptor folding or proper localization.
  • This study reveals distinct molecular mechanisms for trafficking different protein classes to neuronal cilia.

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