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Updated: May 19, 2026
06:32
Quadruple Immunostaining of the Olfactory Bulb for Visualization of Olfactory Sensory Axon Molecular Identity Codes
Published on: June 5, 2017
Neurog1 and Neurog2 coordinately regulate development of the olfactory system
Tarek Shaker1, Daniel Dennis, Deborah M Kurrasch
1Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, Health Sciences Centre, 3330 Hospital Drive NW, Calgary, Alberta, T2N 4N1, Canada.
Neural Development
|August 22, 2012
Summary
Neurog1 and Neurog2 transcription factors are crucial for olfactory system development. Neurog1 is essential for olfactory bulb formation and sensory neuron innervation, coordinating development between the bulb and epithelium.
Area of Science:
- Developmental Neuroscience
- Genetics
- Molecular Biology
Background:
- Proneural genes, encoding basic helix-loop-helix transcription factors, dictate neuronal identity.
- Neurog1 and Neurog2 specify dorsal telencephalon identity and glutamatergic neurons in the neocortex.
- Their roles in olfactory bulb development, influenced by the olfactory epithelium, were unexamined.
Purpose of the Study:
- Investigate the roles of Neurog1 and Neurog2 in olfactory bulb and epithelium development.
- Determine their function in coordinating olfactory system morphogenesis.
- Assess their cell-autonomous roles in neuronal fate specification.
Main Methods:
- Analysis of Neurog1-/-;Neurog2-/- double mutants and single mutants.
- Cellular analysis of olfactory bulb and olfactory epithelium.
- Examination of neuronal differentiation, proliferation, and migration patterns.
- Assessment of olfactory sensory neuron innervation of the olfactory bulb.
Main Results:
- Neurog1 and Neurog2 are co-expressed in olfactory bulb progenitors; Neurog1 is key in olfactory epithelium progenitors.
- Double mutants lack olfactory bulbs; single mutants show reduced or normal structures.
- Loss of Neurog1/2 impairs glutamatergic neuron differentiation and leads to ectopic interneurons.
- Neurog1 deficiency disrupts olfactory sensory neuron innervation, affecting olfactory bulb proliferation and morphogenesis.
Conclusions:
- Neurog1/2 play a cell-autonomous role in specifying glutamatergic olfactory bulb neurons.
- Neurog1 is essential for olfactory sensory neuron innervation, guiding olfactory bulb development.
- Coordinated olfactory system development relies on Neurog1/2 and tissue interactions between the bulb and epithelium.
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