母源效应蛋白在基因组印记维持中的作用

摘要

基因组印记是指生殖细胞发生过程中双亲基因组发生差异表观修饰，使带有亲代印记的等位基因出现父源或母源单等位基因表达。在配子发生和早期胚胎发育过程中，基因组印记甲基化经历一个去除、重建和维持的复杂过程。这个过程中的任何环节被干扰都将导致印记紊乱，造成胚胎发生、胎盘形成及出生后发育异常。近来研究表明，早期胚胎发育过程中一些母源效应蛋白在印记基因表观调控中起重要作用。为了更好地理解这些母源因子对印记基因建立及维持的作用与机制，文章综述了DPPA3、ZFP57、TRIM28和DNMT1等母源效应因子近年来的相关研究进展，并探讨了这些因子对基因组印记的表观调控机制。%Genomic imprinting is a mechanism of differentially epigenetic modification that restricts monoallelic expression to either the maternally or paternally inherited copy of the gene during gametogenesis. Imprinted methyla-tion undergoes a process of erasure, acquisition, and maintenance during gametogenesis and early embryogenesis. Disruptions in any of these steps may lead to imprinting disorders, resulting in the aberrant development of embryo-genesis, placentation and postnatal growth. Recent studies have shown that maternal-effect proteins are important for the regulation of imprinted gene during the development of preimplantation embryos. In order to obtain a better un-derstanding for the mechanism of maternal-effect proteins in the maintenance of genomic imprints, the recent study progress of maternal-effect proteins, such as DPPA3, ZFP57, TRIM28 and DNMT1, are summarized, and the regula-tion mechanism of these maternal-effect proteins for genomic imprints are discussed.