Caviness Verne S, Nowakowski Richard S, Bhide Pradeep G
Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA.
Trends Neurosci. 2009 Aug;32(8):443-50. doi: 10.1016/j.tins.2009.05.003. Epub 2009 Jul 25.
Each of the five cellular layers of the cerebral neocortex is composed of a specific number of a single predominant 'class' of projection neuron. The projection neuron class is defined by its unique morphology and axonal projections to other areas of the brain. Precursor cell populations lining the embryonic lateral ventricles produce the projection neurons. The mechanisms regulating precursor cell proliferation also regulate total numbers of neurons produced at specific developmental periods and destined to a specific neocortical layer. Because the newborn neurons migrate relatively long distances to reach their final layer destinations, it is often assumed that the mechanisms governing acquisition of neuronal-class-specific characteristics, many of which become evident after neuron production, are independent of the mechanisms governing neuron production. We review evidence that suggests that the two mechanisms might be linked via operations of Notch1 and p27(Kip1), molecules known to regulate precursor cell proliferation and neuron production.
大脑新皮层的五个细胞层中的每一层都由特定数量的单一主要“类”投射神经元组成。投射神经元类由其独特的形态和向大脑其他区域的轴突投射来定义。位于胚胎侧脑室的前体细胞群产生投射神经元。调节前体细胞增殖的机制也调节在特定发育阶段产生并注定进入特定新皮层层的神经元总数。由于新生神经元迁移相对较长的距离以到达其最终的层目的地，人们常常认为，控制神经元类特异性特征获得的机制（其中许多在神经元产生后变得明显）与控制神经元产生的机制无关。我们综述了相关证据，这些证据表明这两种机制可能通过Notch1和p27(Kip1)的作用联系起来，这两种分子已知可调节前体细胞增殖和神经元产生。
