Histone modifications play important roles in regulating chromatin dynamic changes. In this study, acetylated histone H3 lysine 9 and 18 (H3K9ac and H3K18ac), acetylated histone H4 lysine 5 and 8 (H4K5ac and H4K8ac), tri-methylation histone H3 lysine 4 (H3K4me3), di-methylation histone H3 lysine 9 (H3K9me2) are investigated in bovine oocytes, zygote, and preimplantation. During meiosis, H3K9ac and H3K18ac are erased after germinal vesicle breakdown, H4K8ac is erased after metaphase I (MI). Although H4K5ac is erased at MI, it is redetectable after this stage. However, histone methylations have no significant change during meiosis. During fertilization, intensive H4K5ac and H4K8ac are resumed on male and female chromatins at postfertilization 4 and 8 hr, respectively. H3K9ac and H3K18ac are resumed on both male and female chromatins at postfertilization 8 and 12 hr, respectively. H3K4me3 and H3K9me2 gradually increased on male chromatin after postfertilization 8 hr, while these two signals on female chromatin are detectable from postfertilization 2-18 hr. During embryo cleavage, H3K9ac, H3K18ac, and H3K4me3 are reduced at 8-cell stage, and then start to increase. H4K5ac, H4K8ac, and H3K9me2 increase after the 4-cell stage. At interphase, H4K5ac and H4K8ac are more intensive in nuclear periphery from 2- to 8-cell stages. During mitosis, the signal of H4K8ac is intensive at chromosome periphery. In summary, during both oocyte meiosis and fertilization, the dynamic changes of both histone acetylations and methylations happen in a process of lysine residue-specific and species-specific. During preimplantation development, the dynamic patterns of both H3K9ac and H3K18ac are similar to that of H3K4me3, while the dynamic pattern of H4K5ac is similar to that of H4K8ac. These results will be helpful for understanding the effect of histone posttranslational modifications on bovine reproduction and development.

中文翻译：

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牛卵母细胞，受精卵和植入前胚胎中组蛋白乙酰化和甲基化的动态变化。

组蛋白修饰在调节染色质动态变化中起重要作用。在这项研究中，乙酰化组蛋白H3赖氨酸9和18（H3K9ac和H3K18ac），乙酰化组蛋白H4赖氨酸5和8（H4K5ac和H4K8ac），三甲基化组蛋白H3赖氨酸4（H3K4me3），二甲基化组蛋白H3赖氨酸9（H3K4me3） ）在牛卵母细胞，合子和植入前进行了研究。在减数分裂期间，生胚囊破裂后H3K9ac和H3K18ac被清除，中期I（MI）后H4K8ac被清除。尽管H4K5ac在MI处已删除，但在此阶段之后可以重新检测到。但是，组蛋白甲基化在减数分裂过程中没有显着变化。受精期间，分别在受精后4小时和8小时对雄性和雌性染色质恢复密集的H4K5ac和H4K8ac。H3K9ac和H3K18ac分别在受精后8小时和12小时恢复在男性和女性染色质上。受精后8小时，雄性染色质上的H3K4me3和H3K9me2逐渐升高，而受精后2-18小时可检测到雌性染色质上的这两个信号。在胚胎切割过程中，H3K9ac，H3K18ac和H3K4me3在8细胞阶段减少，然后开始增加。在4单元阶段之后，H4K5ac，H4K8ac和H3K9me2增加。在相间阶段，H4K5ac和H4K8ac在2至8单元阶段的核外围更为密集。在有丝分裂过程中，H4K8ac的信号在染色体周围集中。总之，在卵母细胞减数分裂和受精过程中，组氨酸乙酰化和甲基化的动态变化发生在赖氨酸残基特异性和物种特异性过程中。在植入前的发育过程中，H3K9ac和H3K18ac的动态模式与H3K4me3相似，而H4K5ac的动态模式与H4K8ac类似。这些结果将有助于理解组蛋白翻译后修饰对牛繁殖和发育的影响。