Ccdc25 regulates neurogenesis during the brain development

During brain development, the proliferation and differentiation of neural stem cells (NSCs) are precisely regulated. Defects in embryonic brain development can lead to serious developmental disorders. The cerebral cortex is the most evolved and complicated structure in the mammalian brain. The process of neuronal production, also known as neurogenesis, plays crucial roles in cerebral development and can affect the function of the neocortex. Ccdc25 is a newly discovered molecule. It has been proved that it can play an important role in tumor. However, its function in neural systems is unclear. In this study, we find that in early embryonic development, Ccdc25 can express in the brain. Suppression of the Ccdc25 mediated by shRNAs causes the increase of the Ki67- or BrdU-positive NSCs proliferation and inhibits the premature terminal mitosis and neuronal differentiation. Simultaneously, overexpression of Ccdc2525 inhibits the proliferation and promotes the differentiation of NSCs. Knockdown of Ccdc25 also affects neuronal maturation, the number of branches of neurons cultured in vitro decreased, and the number of axons became shorter. We also examined the expression profile of NSCs when Ccdc25 was knocked down by RNA sequencing technique. We found that Ccdc25 regulates the development of NSCs through Egr1. Egr1 knockdown can result in a phenotype similar to Ccdc25, while the overexpression of Egr1 can also rescue the phenotype of Ccdc25 knockdown. In conclusion, Ccdc25 can affect the proliferation and differentiation of NSCs and the maturation of neuron.