中心体家族成员CEP295基因突变通过ATM/ATR信号通路导致原发性小头畸形的致病机制研究

原发性小头畸形（PM）是一种宫内发育性神经源性疾病，染色体畸变、基因突变等是主要致病因素，但其致病基因和机制目前仍未完全明确。课题组前期利用家系全外显子组测序技术并联合国际病例共享平台，鉴定到了新的致病基因中心体蛋白295（CEP295）。中心体蛋白家族对细胞有丝分裂、细胞周期调控以及维持基因组稳定性至关重要，已发现部分家族成员突变可导致脑发育异常。初步实验证实Cep295在小鼠胚胎脑组织中高表达，并参与ATM/ATR信号通路介导的细胞周期调控，提示其突变可能影响脑的发育。本项目拟建立CEP295敲除细胞系，研究其在细胞有丝分裂和细胞周期调控中的作用；通过构建Cep295敲除小鼠模型，探讨其对颅脑结构和功能发育的影响；在细胞和动物水平分析CEP295突变通过ATM/ATR信号通路调控细胞周期与增殖的机制。从而阐明CEP295基因突变导致PM的分子机理，为脑发育疾病的产前诊断与治疗奠定基础。

Primary microcephaly (PM) is an intrauterine, developmental and neurogenic disorder. Chromosome aberration and gene variants are the main pathogenic factors. However, the pathogenic genes and pathogenesis of PM are still unclear. Previously, a novel PM pathogenic gene (centrosome protein 295, CEP295 gene) was identified via trio-whole exome sequencing and matching to an international case sharing platform. CEP family plays a vital role in cell mitosis, cell cycle regulation and genomic stability. Mutations in certain CEP family members have been found to cause abnormal brain development. Preliminary studies confirmed that Cep295 gene is highly expressed in embryonic brain tissue of mice and involved in cell cycle regulation, indicating that its variants could lead to abnormal brain development. This project intends to construct CEP295 knockout cell lines and study its roles in cell mitosis and cell cycle regulation; to create Cep295 knockout mice model and explore its effects on brain structure and function development; to analyze the mechanism of regulating cell cycle and proliferation through ATM/ATR pathway under the cellular and animal levels by using classical molecular biology methods. The research will clarify the molecular mechanism of PM caused by CEP295 gene variants and lay a foundation for prenatal diagnosis and treatment of brain development diseases.