c—myc在大鼠耳蜗组织发育和耳蜗前体细胞分化过程中的表达变化

The Changes of the c-myc expression Levels in Rat Cochlear Development and Cochlear Progenitor Cell Differentiation

目的通过检测c—myc基因在大鼠耳蜗组织发育及前体细胞分化过程中的表达情况，探讨其在哺乳动物耳蜗发育中的作用。方法①取E10、E15、P1、P7和P14的SD大鼠耳蜗组织，应用RT--PCR、Western blot的方法检测c-myc在大鼠耳蜗组织发育过程中的表达情况。②取耳蜗前体细胞和分化7天后的分化细胞，用RT-PCR、免疫细胞化学染色和Western blot的方法检测c—myc在耳蜗前体细胞分化过程中的表达情况。结果从胚胎至出生后的耳蜗发育过程中，c-myc表达量呈现逐渐下降趋势；在前体细胞的分化过程中，c-myc的表达量也呈现下降趋势。结论c-myc可能参与调控大鼠耳蜗组织的发育及前体细胞的分化。

Objective The c-myc oncogene is a major regulator for cell proliferation, growth and apoptosis. However, the role of this gene in the mammalian cochlear development is still unclear. To explore the role of this gene in cochleae, the c-myc expression was assessed in the development of rat cochlear tissues and the differentiation of progenitor cells. Methods RT-PCR was used to detect the c-myc mRNA expression in the cochlear tissues, the cochlear progenitor cells （CPCs） and the differentiated cells. The cochlear tissues were excised from El0, E15, P1, P7 and P14 rats, respectively. The differentiated cells were cultured for 7 days and the cell spheres were collected for further assay. Western blotting was used to detect c-myc protein expression in the CPCs, the differentiated cells cultured for 7 days and the cochlear tissues （E10, E15, P1, P7 and P14）. The immunocytochemistry was also utilized to observe c-myc protein expression in the differentiated cells and the cell spheres. Results The results showed that the c-myc level in cochlear tissues decreased gradually from embryonic to newborn period. The c-myc level also fell down during the differentiation of CPCs. Conclusion It indicates that c-myc might be involved in the modulation of rat cochlear development and CPCs differentiation.