中国科学院动物研究所康乐团队的研究认为大型基因组的染色质动力学为蝗虫的多表型和X0剂量补偿提供了见解。这一研究成果发表在2025年9月1日出版的国际学术期刊《自然—遗传学》上。

在这里，该团队生成了沙漠蝗虫和迁徙蝗虫的染色体水平基因组，以及后者的全面染色质图谱。课题组人员发现基因组扩大与扩展的内含子区域中增强子数量的增加有关。为了探索扩展增强子的功能，该研究组确定了一个远端增强子，它有助于独居和群居蝗虫之间的行为差异。在X0性别系统中，H4K16ac的富集和H4K20me1的缺失维持了雄性体细胞中X连锁表达的平衡。值得注意的是，距离依赖的H4K16ac富集在基因间区域逐渐减少，揭示了大基因组中特殊的剂量补偿机制。

此外，距离依赖的H4K16ac导致最近从常染色体易位的X连锁基因的剂量补偿进化滞后。因此，扩展的内含子和基因间区域在大基因组中形成了独特的染色质调控景观。

据悉，蝗虫的特点是基因组大、多表型和X0性别决定系统。

附：英文原文

Title: Chromatin dynamics of a large-sized genome provides insights into polyphenism and X0 dosage compensation of locusts

Author: Liu, Qing, Jiang, Feng, Li, Ran, Liu, Shanlin, Fang, Wenjing, Li, Xiao, Hu, Ting, Feng, Lianyun, Zhang, Jie, Liu, Zhikang, He, Jing, Guo, Wei, Wang, Xianhui, Sun, Zongyi, Li, Jingjing, Gao, Yunan, Yi, Jiacheng, Li, Qiye, Wang, Xiaoxiao, Wei, Liya, Kang, Le

Issue&Volume: 2025-09-01

Abstract: Locusts are characterized by a large genome size, polyphenism and an X0 sex determination system. Here we generated chromosome-level genomes for both desert and migratory locusts, as well as a comprehensive chromatin map for the latter. We found that genome enlargement is associated with an increased number of enhancers in expanded intronic regions. To explore the function of expanded enhancers, we identified a distal enhancer that contributes to behavioral differences between solitary and gregarious locusts. In the X0 sex system, H4K16ac enrichment and H4K20me1 depletion maintain balanced X-linked expression in male soma. Notably, the distance-dependent H4K16ac enrichment diminishes gradually in intergenic regions, revealing a special dosage compensation mechanism in large genomes. Furthermore, the distance-dependent H4K16ac results in a lag in the evolution of dosage compensation for the X-linked genes translocated recently from autosomes. Therefore, expanded intronic and intergenic regions shape a distinct chromatin regulation landscape in large genomes.

DOI: 10.1038/s41588-025-02330-y

Source: https://www.nature.com/articles/s41588-025-02330-y