HAUS蛋白复合体在卵母细胞成熟和胚胎发育早期中的功能研究

Chromosome aneuploidy is the leading known cause of congenital birth defects and spontaneous abortions, and spindle microtubule is important for the accurate chromosome alignment and separation. In mitosis, HAUS complex could nucleate new microtubules on the pre-existing microtubules, stable the spindle and promote the chromosome separation accurately. But little is known about the function of HAUS complex in mammalian oocyte maturation and the early stage of embryo development. Therefore, we would analyze the localization and expression of HAUS complex during oocyte maturation and the early stage of the embryo development in mouse and human by immunofluorescence and RT-qPCR; study the function of HAUS complex in spindle formation, chromosome separation and embryo implantation through morpholino; explore its relationship with γ-tubulin, TPX2 and HURP. At last, we would also analyze the expression patterns of HAUS complex in human embryos with poor morphology. Our project would provide important novel information for further understanding the molecular mechanism of spindle formation in meiosis and early stage of embryo development, and shed light on the underling mechanisms of the chromosome aneuploidy, congenital birth defects and spontaneous abortions.

染色体非整倍性是先天性出生缺陷和自发流产的重要原因，而纺锤体的正确组装对于染色体分离具有重要的作用。在有丝分裂中，HAUS蛋白复合体可以聚合微管，促进纺锤体的稳定，影响染色体的排列和分离，但是其在哺乳动物卵母细胞成熟和胚胎发育早期中的功能却知之甚少。本研究拟利用免疫荧光、RT-qPCR等方法分析HAUS蛋白复合体在小鼠、人卵母细胞成熟和胚胎发育早期中的定位和表达；通过注射mopholino敲低HAUS,研究其对纺锤体组装和染色体排列、分离以及小鼠胚胎着床、产仔的影响；通过检测其与γ-tubulin、TPX2和HURP的相互关系探索其可能的作用机制；同时本研究还将比较HAUS蛋白在高龄妇女IVF胚胎、形态差胚胎和正常胚胎中的表达差异。本研究将为阐明胚胎染色体非整倍性、自发流产和先天性出生缺陷提供参考。

纺锤体的正确组装是细胞分裂中染色体准确分离的关键，而HAUS蛋白复合体对于小鼠细胞的纺锤体组装具有重要的作用，但是HAUS蛋白复合体在卵母细胞成熟和早期胚胎发育中的作用却知之甚少。我们通过免疫荧光染色，检测了HAUS蛋白复合体在小鼠卵母细胞成熟中定位于纺锤体上，通过western blot检测发现其在小鼠胚胎发育早期均有稳定的表达。通过特异性的morpholino敲低后发现小鼠的染色体分离和纺锤体组装均出现不同程度的异常，并最终降低了小鼠胚胎的活产率。通过对人2细胞期阻滞的胚胎的RNA转录组测序，发现大量基因表达异常。