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Updated: Jul 4, 2026
06:32
Quadruple Immunostaining of the Olfactory Bulb for Visualization of Olfactory Sensory Axon Molecular Identity Codes
Published on: June 5, 2017
Prominent roles for odorant receptor coding sequences in allelic exclusion
Minh Q Nguyen1, Zhishang Zhou, Carolyn A Marks
1National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA.
Cell
|November 30, 2007
Summary
Mammalian olfactory receptor (OR) gene expression is tightly controlled, with a feedback system within the OR-coding sequence ensuring single-receptor expression per neuron. This study reveals a method to express any OR in most olfactory sensory neurons.
Area of Science:
- Neuroscience
- Genetics
- Molecular Biology
Background:
- Mammalian olfactory receptors (ORs) are essential for olfactory system organization.
- Mechanisms governing OR gene expression are not fully understood.
Purpose of the Study:
- To investigate the regulatory mechanisms of OR gene expression.
- To identify elements within the OR-coding sequence that control expression.
- To develop a method for expressing ORs in olfactory sensory neurons (OSNs).
Main Methods:
- Utilized a transgenic approach to study OR gene regulation.
- Introduced transgenic OR-coding sequences into OSNs.
- Experimentally manipulated the timing of OR expression in developing neurons.
Main Results:
- OSNs can support multiple ORs, but normally express only one due to regulatory controls.
- OR-coding sequences themselves participate in a feedback system suppressing transgene expression.
- Precocious expression in immature neurons bypasses suppression, enabling widespread OR expression (approx. 90% of OSNs).
Conclusions:
- OR gene expression involves intricate feedback mechanisms, including elements within the OR-coding sequence.
- A novel method allows for the expression of any OR in a majority of OSNs, offering insights into olfactory receptor biology.
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