南方科技大学吴柘研究小组近日取得一项新成果。他们的研究揭示了拟南芥雄性配体中独特的染色质特征。这一研究成果于2023年3月2日发表在国际学术期刊《自然—遗传学》上。

研究人员分析了整个拟南芥雄性种系发育过程中的组蛋白修饰。研究发现精子细胞具有广泛的表观染色质二价性，即在H3K4me3或H3K27me3区域再产生H3K27me3或H3K4me3修饰。这些二价结构域与不同的转录状态相关。体细胞H3K27me3通常在精子中减少，而H3K27me3仅在700个发育基因中观察到明显丢失。组蛋白变体H3.10的产生有助于建立精子染色质身份，而不会对体细胞H3K27me3的重置产生强烈影响。在植物细胞核被抑制的基因上含有数千个特定的H3K27me3结构域，而授粉相关基因则高度表达并具有H3K4me3修饰。

该研究表明假定的染色质二价和发育调节因子中H3K27me3的限制重置是植物多能精子的关键特征。

附：英文原文

Title: Distinct chromatin signatures in the Arabidopsis male gametophyte

Author: Zhu, Danling, Wen, Yi, Yao, Wanyue, Zheng, Haiyan, Zhou, Sixian, Zhang, Qiqi, Qu, Li-Jia, Chen, Xi, Wu, Zhe

Issue&Volume: 2023-03-02

Abstract: Epigenetic reprogramming in the germline contributes to the erasure of epigenetic inheritance across generations in mammals but remains poorly characterized in plants. Here we profiled histone modifications throughout Arabidopsis male germline development. We find that the sperm cell has widespread apparent chromatin bivalency, which is established by the acquisition of H3K27me3 or H3K4me3 at pre-existing H3K4me3 or H3K27me3 regions, respectively. These bivalent domains are associated with a distinct transcriptional status. Somatic H3K27me3 is generally reduced in sperm, while dramatic loss of H3K27me3 is observed at only ~700developmental genes. The incorporation of the histone variant H3.10 facilitates the establishment of sperm chromatin identity without a strong impact on resetting of somatic H3K27me3. Vegetative nuclei harbor thousands of specific H3K27me3 domains at repressed genes, while pollination-related genes are highly expressed and marked by gene body H3K4me3. Our work highlights putative chromatin bivalency and restricted resetting of H3K27me3 at developmental regulators as key features in plant pluripotent sperm.

DOI: 10.1038/s41588-023-01329-7

Source: https://www.nature.com/articles/s41588-023-01329-7