Objective: To study the expression characteristics of NeuN (neuron-specific nuclear protein/neuronal nuclei) in the development of mice olfactory bulb and epithelium.
Method: The expression of NeuN in the heads of E9.5, E11.5, E14.5, E17.5, newborn and adult mice were examined by immunofluorescence method.
Result: NeuN was expressed in mature neural cells at the margin area of olfactory bulb of new natal mice while the layers of olfactory bulb could not be distinguished. Mature neural cells expressing NeuN aggregated in the granule cells layer, when layers of olfactory bulb of adult mice were clearly formed. The expression of NeuN could not be observed in bipolar olfactory receptor neurons (ORN) in olfactory epithelium.
Conclusion: It is usually believed that NeuN is expressed in most mature neurons. However, during the development of olfactory bulb and epithelium, NeuN is expressed only in mature neural cells migrating from margin area to the inner granule cells layer of olfactory bulb. It is proposed that the migration of granule cells in olfactory bulb might be related to the formation of smell pattern.