Serizawa Shou, Miyamichi Kazunari, Nakatani Hiroko, Suzuki Misao, Saito Michiko, Yoshihara Yoshihiro, Sakano Hitoshi
Department of Biophysics and Biochemistry, Graduate School of Science, University of Tokyo, Tokyo 113-0032, Japan.
Science. 2003 Dec 19;302(5653):2088-94. doi: 10.1126/science.1089122. Epub 2003 Oct 30.
In the mouse olfactory system, each olfactory sensory neuron (OSN) expresses only one odorant receptor (OR) gene in a monoallelic and mutually exclusive manner. Such expression forms the genetic basis for OR-instructed axonal projection of OSNs to the olfactory bulb of the brain during development. Here, we identify an upstream cis-acting DNA region that activates the OR gene cluster in mouse and allows the expression of only one OR gene within the cluster. Deletion of the coding region of the expressed OR gene or a naturally occurring frame-shift mutation allows a second OR gene to be expressed. We propose that stochastic activation of only one OR gene within the cluster and negative feedback regulation by that OR gene product are necessary to ensure the one receptor-one neuron rule.
在小鼠嗅觉系统中，每个嗅觉感觉神经元（OSN）以单等位基因且相互排斥的方式仅表达一种气味受体（OR）基因。这种表达形成了在发育过程中OR指导的OSN轴突投射至大脑嗅球的遗传基础。在此，我们鉴定出一个上游顺式作用DNA区域，其激活小鼠中的OR基因簇，并允许该簇内仅一个OR基因表达。已表达的OR基因编码区的缺失或自然发生的移码突变会使第二个OR基因得以表达。我们提出，簇内仅一个OR基因的随机激活以及该OR基因产物的负反馈调节对于确保一个受体-一个神经元规则是必要的。
