Isolation and characterization of the genes regulating the neuronal defferentiation.

视黄酸诱导P19 EC细胞向神经元细胞分化。在神经元分化过程中，许多细胞发生DNA断裂的凋亡。因此，P19 EC细胞的神经元分化是研究小鼠胚胎发育过程中神经元分化和凋亡的良好模型。本研究分离了维甲酸诱导P10 EC细胞向神经元分化过程中表达的多种基因。1)Caspase-3和Caspase-7参与维甲酸诱导P19 EC细胞凋亡。2)寡糖基转移酶48 kDa，其缺陷诱导酵母死亡。3)RA 70是一个视黄酸诱导的新基因，在小鼠胚胎早期发育的神经系统中表达。4)RA 175是一个在神经发生过程中在上皮组织和神经系统中表达的新基因。由于RA 175在上皮组织中共表达，RA 175可能参与了声刺猬补丁信号诱导的形态发生。5)RA 375是在神经系统中表达的具有锌指结构的基因。在神经外组织中，RA 70在精原细胞中表达，但在精子发生过程中不表达，表明RA 70也参与减数分裂。

P19EC cells differentiate into neuronal cells by retinoic acid. During neuronal differentiation, many cells undergo apoptosis with DNA fragmentatoin. Thus neuronal differentiation of P19EC cells is a good model for the neuronal differentiation and apoptosis during development of mouse embryos. In the present study, we isolated various genes expressed during neruonal differentiation of P10EC cells induced by retinoic acid. 1) Caspase-3 and -7, which are involved in the apoptosis of P19EC cells induced by retinoic acid. 2) Oligosaccharyltransferase 48kDa, whose defect induces the death of yeast. 3) RA70, a retinoic acid inducible new gene, which is expressed in the nervous system of the early developmental stage of mouse embryos. 4) RA175, a new gene, which is expressed in epithelial tissues and nervous system during neurogenesis. Since RA175 is coexpressed in sonic hedgehog in epithelial tissues, RA175 may be involved in the morphogenesis induced by sonic hedgehog-patched signal. 5) RA375, which is the gene with zinc-finger motif expressed in the nervous sytem. In extra-neural tissues, RA70 is expressed in spermatogonia, but not spermatid during spermatogenesis, suggesting that RA70 is also involved in the meiosis.