State Key Laboratory for Biocontrol, School of Marine Sciences, Sun Yat-Sen University, Zhuhai, Guangdong 519000, China.
China-ASEAN Belt and Road Joint Laboratory on Mariculture Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong 519000, China.
Zool Res. 2023 Mar 18;44(2):287-302. doi: 10.24272/j.issn.2095-8137.2022.462.
Due to the difficulty in accurately identifying structural variants (SVs) across genomes, their impact on -regulatory divergence of closely related species, especially fish, remains to be explored. Recently identified broad H3K4me3 domains are essential for the regulation of genes involved in several biological processes. However, the role of broad H3K4me3 domains in phenotypic divergence remains poorly understood. and are closely related but divergent in several phenotypic traits, making them an ideal model to study -regulatory evolution in sister species. Here, we generated chromosome-level genomes of and , with assembled genome sizes of 716.35 and 740.54 Mb, respectively. The evolutionary histories of and were studied by inferring dynamic changes in ancestral population sizes. To explore the genetic basis of adaptation in and , we performed gene family expansion and contraction analysis and identified positively selected genes (PSGs). To investigate the role of SVs in -regulatory divergence of closely related fish species, we identified high-quality SVs as well as divergent H3K27ac and H3K4me3 domains in the genomes of and . Integrated analysis revealed that -regulatory divergence caused by SVs played an essential role in phenotypic divergence between and . Additionally, divergent broad H3K4me3 domains were mostly associated with cancer-related genes in and and contributed to their phenotypic divergence.
由于在整个基因组中准确识别结构变异(SVs)具有一定难度,它们对密切相关物种(尤其是鱼类)的调控分化的影响仍有待探索。最近鉴定的广泛的 H3K4me3 结构域对于调节涉及多个生物学过程的基因至关重要。然而,广泛的 H3K4me3 结构域在表型分化中的作用仍知之甚少。 和 在几个表型特征上密切相关但存在分化,这使它们成为研究姐妹物种中调控进化的理想模型。在这里,我们生成了 和 的染色体水平基因组,组装的基因组大小分别为 716.35 和 740.54Mb。通过推断祖先种群规模的动态变化,研究了 和 的进化历史。为了探索 和 适应的遗传基础,我们进行了基因家族扩张和收缩分析,并鉴定了正选择基因(PSGs)。为了研究 SVs 在密切相关鱼类物种的调控分化中的作用,我们在 和 的基因组中鉴定了高质量的 SVs 以及分化的 H3K27ac 和 H3K4me3 结构域。综合分析表明,SVs 引起的调控分化在 和 之间的表型分化中起着至关重要的作用。此外,分化的广泛的 H3K4me3 结构域主要与 和 中的癌症相关基因相关,并有助于它们的表型分化。