Eagleson K L, Ferri R T, Levitt P
Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School-UMDNJ, Piscataway, NJ 08854, USA.
Cereb Cortex. 1996 May-Jun;6(3):540-9. doi: 10.1093/cercor/6.3.540.
We previously identified an interaction between collagen type IV and the EGF receptor that regulates the differentiation of a limbic cortical phenotype in vitro (Ferri and Levitt, 1995). In the present study, we map the expression of the EGF receptor and collagen type IV in the embryonic telencephalon of the rat. At embryonic day (E) II, the earliest age examined, both proteins are coexpressed throughout the ventricular zone in the cerebral wall; this zone remains immunoreactive throughout corticogenesis (E14-E19). The cells comprising the subventricular zone are the most intensely immunoreactive for the EGF receptor, although little collage type IV is detected in this region. In contrast, postmitotic neurons that leave the proliferative zones are negative for the receptor. Moreover, during the peak of neuronal migration, the intermediate zone lacks collagen type IV immunoreactivity. Neurons that settle in the cortical plate once again exhibit EGF receptor immunoreactivity; this same zone is devoid of collagen type IV. By E19, coexpression of both proteins is evident only in the rostral extension of the subventricular zone, the pathway of migrating cells leading to the olfactory bulb. The temporal and spatial overlap of the EGF receptor and collage type IV in the cortical progenitor pool in vivo indicates that these molecules may participate in the initial decisions of neuronal differentiation. Their modified distribution during cortical maturation suggests a changing role for both proteins.
我们先前鉴定出IV型胶原蛋白与表皮生长因子（EGF）受体之间存在相互作用，该相互作用在体外调节边缘皮质表型的分化（费里和莱维特，1995年）。在本研究中，我们绘制了大鼠胚胎端脑内EGF受体和IV型胶原蛋白的表达图谱。在胚胎第11天（E11），即检测的最早时间点，两种蛋白在脑壁的整个脑室区共表达；在整个皮质发生过程中（E14 - E19），该区域一直保持免疫反应性。构成脑室下区的细胞对EGF受体的免疫反应最强，尽管在该区域检测到的IV型胶原蛋白很少。相比之下，离开增殖区的有丝分裂后神经元对该受体呈阴性反应。此外，在神经元迁移高峰期，中间区缺乏IV型胶原蛋白免疫反应性。定居在皮质板的神经元再次表现出EGF受体免疫反应性；同一区域没有IV型胶原蛋白。到E19时，两种蛋白的共表达仅在脑室下区的 Rostral 延伸部分明显，这是迁移细胞通向嗅球的路径。体内皮质祖细胞池中EGF受体和IV型胶原蛋白在时间和空间上的重叠表明，这些分子可能参与神经元分化的初始决定。它们在皮质成熟过程中分布的改变表明这两种蛋白的作用在发生变化。
