Yang Peng, Wu Warren, Macfarlan Todd S
Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
Bioessays. 2015 Jan;37(1):52-9. doi: 10.1002/bies.201400072. Epub 2014 Oct 18.
The mammalian egg employs a wide spectrum of epigenome modification machinery to reprogram the sperm nucleus shortly after fertilization. This event is required for transcriptional activation of the paternal/zygotic genome and progression through cleavage divisions. Reprogramming of paternal nuclei requires replacement of sperm protamines with canonical and non-canonical histones, covalent modification of histone tails, and chemical modification of DNA (notably oxidative demethylation of methylated cytosines). In this essay we highlight the role maternal histone variants play during developmental reprogramming following fertilization. We discuss how reduced maternal histone variant incorporation in somatic nuclear transfer experiments may explain the reduced viability of resulting embryos and how knowledge of repressive and activating maternal factors may be used to improve somatic cell reprogramming.
哺乳动物的卵子在受精后不久会利用多种表观基因组修饰机制对精子细胞核进行重编程。这一过程对于父本/合子基因组的转录激活以及卵裂的进行是必需的。父本细胞核的重编程需要用典型和非典型组蛋白取代精子鱼精蛋白、组蛋白尾部的共价修饰以及DNA的化学修饰（特别是甲基化胞嘧啶的氧化去甲基化）。在本文中，我们重点介绍了母体组蛋白变体在受精后发育重编程过程中所起的作用。我们讨论了在体细胞核移植实验中母体组蛋白变体掺入减少如何解释所产生胚胎活力的降低，以及对抑制性和激活性母体因子的了解如何可用于改善体细胞重编程。
