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Updated: Jul 25, 2026
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High-throughput Analysis of Mammalian Olfactory Receptors: Measurement of Receptor Activation via Luciferase Activity
Published on: June 2, 2014
Molecular messengers of olfaction
1Johns Hopkins University School of Medicine, Dept of Neuroscience, Baltimore, MD 21205.
Trends in Neurosciences
|December 1, 1992
Summary
Recent advances clarify olfactory signal transduction. Odorants activate G protein-coupled receptors, triggering second messenger pathways like cyclic AMP and calcium, crucial for smell perception and adaptation.
Area of Science:
- Neuroscience
- Molecular Biology
- Biochemistry
Background:
- Olfactory signal transduction mechanisms were not fully understood.
- Recent molecular cloning identified a large family of odorant receptors.
- These receptors share a seven-transmembrane-domain motif, suggesting G protein association.
Purpose of the Study:
- To elucidate the molecular mechanisms underlying olfactory signal transduction.
- To investigate the role of second messengers in odorant detection.
Main Methods:
- Molecular cloning of odorant receptors.
- Biochemical assays on isolated olfactory cilia and neuronal cultures.
- Measurement of adenylyl cyclase, phosphoinositide, and cGMP turnover.
- Localization of enzymes within olfactory cilia.
Main Results:
- A large family of putative odorant receptors was identified in the olfactory epithelium.
- Odorants rapidly enhanced adenylyl cyclase and phosphoinositide turnover.
- A calcium-calmodulin-dependent phosphodiesterase was localized to olfactory cilia.
- Odorants were shown to modulate cGMP levels in olfactory neurons.
Conclusions:
- Olfactory signal transduction involves G protein-coupled receptors and multiple second messenger systems.
- Calcium ions play a critical role in the olfactory pathway.
- Multiple second messengers likely contribute to the fine-tuning and desensitization of olfaction.
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