Roskams A J, Cai X, Ronnett G V
Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA.
Neuroscience. 1998 Mar;83(1):191-200. doi: 10.1016/s0306-4522(97)00344-8.
The olfactory neuroepithelium retains the unique capacity to produce a new set of mature neurons every three to four weeks from a precursor population situated at the base of the epithelium. It is not known however, whether developing olfactory neurons in the adult rat follow the same program that is initiated embryonically. By tracking the expression of beta-III tubulin (by immunoreactivity to TuJ-1, an isoform-specific antibody) throughout embryogenesis, we have demonstrated a commitment to the olfactory neuron lineage in a subset of cells in the embryonic olfactory placode and followed their development into adulthood. We have also shown that this developmental pattern of beta-III tubulin expression is recapitulated in neurons undergoing a synchronized neurogenic response to either physical or chemical lesion in the adult neuroepithelium. The embryonic expression pattern reported here is similar to, but earlier than that reported for other markers of developing neurons, such as growth-associated protein-43 and neural cell adhesion molecule. The results of these studies suggest the retention of a conserved neurogenic program from embryonic to adult life in the olfactory neuron and, in addition, support the use of a readily accessible system such as the regenerating olfactory neuroepithelium as an alternative means of studying genes which may be crucial to normal neuronal development.
嗅觉神经上皮具有独特的能力，每三到四周就能从位于上皮底部的前体细胞群中产生一组新的成熟神经元。然而，尚不清楚成年大鼠中正在发育的嗅觉神经元是否遵循胚胎期启动的相同程序。通过在整个胚胎发育过程中追踪β-III微管蛋白的表达（通过对TuJ-1的免疫反应性，一种亚型特异性抗体），我们已经证明胚胎嗅觉基板中的一部分细胞会定向分化为嗅觉神经元谱系，并追踪它们发育至成年。我们还表明，在成年神经上皮中对物理或化学损伤产生同步神经源性反应的神经元中，β-III微管蛋白的这种发育模式会重现。此处报道的胚胎期表达模式与其他发育中神经元的标志物（如生长相关蛋白-43和神经细胞粘附分子）报道的模式相似，但更早出现。这些研究结果表明，嗅觉神经元从胚胎期到成年期保留了一个保守的神经发生程序，此外，支持使用易于获取的系统，如再生的嗅觉神经上皮，作为研究可能对正常神经元发育至关重要的基因的替代方法。
