The Expression and Nuclear Deposition of Histone H3.1 in Murine Oocytes and Preimplantation Embryos
The Expression and Nuclear Deposition of Histone H3.1 in Murine Oocytes and Preimplantation Embryos
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DOI：
10.1262/jrd.2012-074
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发表时间：
2012-10-01
影响因子：
1.8
通讯作者：
Aoki, Fugaku
中科院分区：
文献类型：
--
作者：
Kawamura, Machika;Akiyama, Tomohiko;Aoki, Fugaku
分化的卵母细胞通过受精获得全能性。在这一转变过程中，全基因组染色质重塑发生，从而导致基因表达的改变。然而，染色质结构这种全球性变化的机制尚未完全阐明。组蛋白变异在定义染色质结构中起关键作用，并涉及表观遗传信息的遗传。在本研究中，我们分析了H3.1的核定位和表达，以阐明该组蛋白变体在卵子发生和着床前发育期间染色质重塑中的作用。使用flag标记的H3.1转基因小鼠进行分析发现，尽管Flag-H3.1 mRNA在所有阶段均有表达，但在分化的卵母细胞和桑葚胚期之前的早期着床前胚胎中不存在Flag-H3.1。此外，在染色质中不存在H3.1的阶段，内源性H3.1基因的表达水平较低。这些结果表明，由于组蛋白伴侣的不活性和mRNA的低表达水平，H3.1未被纳入染色质。H3.1的动态意义是根据发育过程中发生的染色质重塑来评估的。
Differentiated oocytes acquire totipotency through fertilization. During this transition, genome-wide chromatin remodeling occurs, which leads to change in gene expression. However, the mechanism that underlies this global change in chromatin structure has not been fully elucidated. Histone variants play a key role in defining chromatin structure and are implicated in inheritance of epigenetic information. In this study, we analyzed the nuclear localization and expression of H3.1 to elucidate the role of this histone variant in chromatin remodeling during oogenesis and preimplantation development. Analysis using Flag-tagged H3.1 transgenic mice revealed that Flag-H3.1 was not present in differentiated oocytes or early preimplantation embryos before the morula stage, although Flag-H3.1 mRNA was expressed at all stages examined. In addition, the expression levels of endogenous H3.1 genes were low at the stages where H3.1 was not present in chromatin. These results suggest that H3.1 is not incorporated into chromatin due to the inactivity of the histone chaperone and low mRNA expression level. The significance of the dynamics of H3.1 is evaluated in terms of chromatin remodeling that takes place during development.