哺乳动物早期胚胎发育过程中X染色体失活的研究进展  

Progress in the Study of X Chromosome Inactivation in Early Mammalian Embryonic Development

作　　者：刘雨辰 杨芷珊 张宇霆[1] 刘忠华[1] 翁晓刚 LIU Yuchen;YANG Zhishan;ZHANG Yuting;LIU Zhonghua;WENG Xiaogang(College of Life Sciences,Northeastern Agricultural University,Harbin 150030,China)

机构地区：[1]东北农业大学生命科学学院,哈尔滨150030

出　　处：《中国细胞生物学学报》2022年第11期2223-2232,共10页Chinese Journal of Cell Biology

基　　金：国家自然科学基金(批准号:32072733)资助的课题

摘　　要：虽然哺乳动物雄性和雌性的性染色体存在显著差异,但是哺乳动物两性间大多数X染色体连锁基因的表达水平相似。这种X染色体剂量补偿是通过X染色体失活(X chromosome inactivation,XCI)实现的,XCI有印记失活和随机失活两种类型。在X染色体失活过程中,长链非编码RNA Xist表达水平的升高驱动了将要失活的那条X染色体沉默的起始,随后一些与Xist结合的RNA结合蛋白会促进Xist在X染色体上的定位并招募各种表观修饰酶复合物,最后完成抑制性修饰的建立和染色体的重塑。目前,关于XCI的认知大部分来源于小鼠上的研究,然而越来越多的证据显示不同物种XCI的调控存在较大差异。该文重点综述了小鼠胚胎发育过程中XCI的建立时期与具体机制、XCI过程中重要的长链非编码RNA以及Xist RNA结合蛋白,并进一步比较了人、小鼠以及食蟹猴XCI的异同。In mammals,although there are significant differences between chromosome X and chromosome Y,most X chromosome linked genes are expressed at similar levels between males and females.This X chromosome dosage compensation is achieved by XCI(X chromosome inactivation).There are two types XCI,imprinted inactivation and random inactivation.The elevated levels of long non-coding RNA Xist expression drive the initiation of silencing the X chromosome.Subsequently,some RNA-binding proteins that bind to Xist play a role in the establishment of inhibitory modifications and chromosome remodeling.So far,most of knowledge of XCI is based on the studies in mice.However,the regulation of XCI varies greatly among different species.This review focuses on an overview of the specific mechanisms of XCI establishment in mouse,the important long non-coding RNAs and Xist RNA-binding proteins involving in the XCI process,and further compares the similarities and differences among human,mouse and cynomolgus monkey XCI.

关 键 词：早期胚胎发育 X染色体失活 XIST Xist RNA结合蛋白 

分 类 号：Q953[生物学—动物学]