Fukuda Atsushi, Umezawa Akihiro, Akutsu Hidenori
Center for Regenerative Medicine, National Center for Child Health and Development, Tokyo, Japan.
Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA.
Methods Mol Biol. 2018;1861:47-53. doi: 10.1007/978-1-4939-8766-5_4.
X-chromosome inactivation (XCI) is established in preimplantation embryos in mice. Prior to the establishment of XCI, expression of the long noncoding RNA (lncRNA) Xist is essential. Xist expression in mouse preimplantation embryos is imprinted, and paternal Xist is predominantly expressed. Due to the manner of imprinting, maternal Xist is always silenced. However, the nature of imprinting to repress maternal Xist is variable. For example, parthenogenetic embryos that are composed of two maternal genomes exhibit maternal Xist derepression during the preimplantation phases. Maintenance of Xist imprinting to repress maternal Xist depends on the chromatin condensation states and the dosage of Rnf12, an essential Xist activator. Therefore, alterations of chromatin states and Rnf12 expression levels lead to maternal Xist derepression. In this chapter, we describe the method for derepressing maternal Xist by various approaches, such as mRNA injection, small molecule treatment, and nuclear transfer.
X染色体失活（XCI）在小鼠植入前胚胎中建立。在XCI建立之前，长链非编码RNA（lncRNA）Xist的表达至关重要。小鼠植入前胚胎中Xist的表达是印记的，父本Xist主要表达。由于印记方式，母本Xist总是沉默的。然而，抑制母本Xist的印记性质是可变的。例如，由两个母本基因组组成的孤雌生殖胚胎在植入前阶段表现出母本Xist去抑制。维持抑制母本Xist的Xist印记取决于染色质凝聚状态和Rnf12（一种必需的Xist激活剂）的剂量。因此，染色质状态和Rnf12表达水平的改变会导致母本Xist去抑制。在本章中，我们描述了通过各种方法使母本Xist去抑制的方法，如mRNA注射、小分子处理和核移植。
