SUMO化修饰对卵母细胞染色体非整倍性的影响

Effect of SUMO Modification on the Chromosomal Aneuploidy in Oocytes

卵母细胞染色体非整倍性是流产和新生儿出生缺陷的主要原因之一,主要源于以下2个方面:(1)Cohesin蛋白复合物丢失导致的姐妹染色单体过早分离型卵母细胞非整倍性;(2)纺锤体动力异常导致完整姐妹染色体对分离异常的非分离型卵母细胞非整倍性。SUMO化修饰作为一种蛋白质翻译后修饰途径,参与了细胞增殖、分化、凋亡以及周期调控等众多生理调控过程。在卵母细胞中,SUMO化修饰既可调节Cohesin蛋白复合物在染色体上的定位,影响过早分离型卵母细胞非整倍性;同时可调节纺锤体动力学,影响非分离型卵母细胞非整倍性。因此,SUMO化修饰对卵母细胞染色体非整倍性具有重要作用,但尚不清楚是通过修饰哪些底物影响卵母细胞非整倍性,其具体分子机制还有待进一步研究。本文从SUMO化修饰对卵母细胞中Cohesin蛋白复合物的作用及其对微管动力学的影响两方面,探讨了SUMO化修饰在姐妹染色单体过早分离型和非分离型卵母细胞非整倍性中的作用。

The chromosomal aneuploidy in oocytes is one of main causes of abortion and neonatal birth defects.It is mainly due to the premature separation of sister chromatid caused by the loss of Cohesin protein complex and the non-disjunction sister chromatids caused by abnormal microtubule dynamics aneuploidy.As a pathway of protein post-translational modification,SUMO modification(or SUMOylation)involves many physiological regulation processes including cell proliferation, differentiation,apoptosis,and cycle regulation.In the oocytes,SUMOylation can regulate the localization of Cohesin protein complex on the chromosome to affect the chromosomal aneuploidy in oocytes caused by premature separation of sister chromatid.On the other hand,SUMOylation can regulate the microtubule dynamics to affect the chromosomal aneuploidy in oocytes caused by non-disjunction sister chromatids.Therefore,SUMOylation plays an important role in regulating the chromosomal aneuploidy of oocytes;the exact mechanisms via which the SUMOylated substrates affect aneuploidy in oocytes remain unclear.This articles reviews the roles of SUMOylation in premature separation and non-isolated chromatid aneuploidy in oocyte from the effects of SUMOylationon Cohesin protein complex and microtubule dynamics.