Epigenetic mechanisms play essential roles in determining distinct cell fates during the development of multicellular organisms. Histone proteins represent crucial epigenetic components that help specify cell identities. Previous work has demonstrated that during the asymmetric cell division of Drosophila male germline stem cells (GSCs), histones H3 and H4 are asymmetrically inherited, such that pre-existing (old) histones are segregated towards the self-renewing GSC whereas newly synthesized (new) histones are enriched towards the differentiating daughter cell. In order to further understand the molecular mechanisms underlying this striking phenomenon, two key questions must be answered: when and how old and new histones are differentially incorporated by sister chromatids, and how epigenetically distinct sister chromatids are specifically recognized and segregated. Here, we discuss recent advances in our understanding of the molecular mechanisms and cellular bases underlying these fundamental and important biological processes responsible for generating two distinct cells through one cell division.

中文翻译：

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不对称分裂干细胞中的不对称组蛋白遗传。


表观遗传机制在确定多细胞生物发育过程中不同的细胞命运方面发挥着重要作用。组蛋白代表了有助于确定细胞身份的关键表观遗传成分。先前的工作表明，在果蝇雄性生殖干细胞（GSC）的不对称细胞分裂过程中，组蛋白 H3 和 H4 是不对称遗传的，因此预先存在的（旧的）组蛋白被分离向自我更新的 GSC，而新合成的（新的）组蛋白则被分离到自我更新的 GSC 中。 ）组蛋白向分化的子细胞富集。为了进一步了解这一惊人现象背后的分子机制，必须回答两个关键问题：新旧组蛋白何时以及如何被姐妹染色单体差异化，以及表观遗传上不同的姐妹染色单体如何被特异性识别和分离。在这里，我们讨论了我们对这些基本且重要的生物过程背后的分子机制和细胞基础的理解的最新进展，这些生物过程负责通过一次细胞分裂产生两个不同的细胞。