中国科学院植物研究所Wei Wang等研究人员合作发现，基因组数据和生态位模型揭示白垩纪领春木科植物异常缓慢的分子演化速度。这一研究成果于2023年12月11日在线发表在国际学术期刊《中国科学—生命科学》上。

研究人员引入了一种整合了系统发生组、比较基因组和生态位建模分析的新方法来研究东亚特有的白垩纪孑遗被子植物领春木科（Eupteleaceae）的分子演化速度。研究人员为领春木科的一个成员（Euptelea pleiosperma）组装了高质量的染色体级核基因组以及叶绿体和线粒体基因组。研究结果表明，领春木科（Eupteleaceae）是毛茛科（Ranunculales）中最基干的一科，是裸子植物中最早分化的目，与其他毛茛科植物共享一个古老的全基因组复制事件。

研究人员发现领春木科的分子演化速度是所观察到的被子植物中最慢的。领春木科在所有三个独立的遗传基因组和三个基因组内的基因中的分子演化速度异常低，这与其保守的基因组结构、祖先的木本习性和保守的生态位要求有关。这些发现揭示了活化石植物在大规模环境变化中的演化和适应，同时也为早期裸子植物的多样化提供了新的见解。

据介绍，活化石是长期持续生态成功的证据。然而，人们对活化石的分子变化是否很小仍然知之甚少，尤其是在植物中。

附：英文原文

Title: Genomic data and ecological niche modeling reveal an unusually slow rate of molecular evolution in the Cretaceous Eupteleaceae

Author: Xiang, Kun-Li, Wu, Sheng-Dan, Lian, Lian, He, Wen-Chuang, Peng, Dan, Peng, Huan-Wen, Zhang, Xiao-Ni, Li, Hong-Lei, Xue, Jia-Yu, Shan, Hong-Yan, Xu, Gui-Xia, Liu, Yang, Wu, Zhi-Qiang, Wang, Wei

Issue&Volume: 2023-12-11

Abstract: Living fossils are evidence of long-term sustained ecological success. However, whether living fossils have little molecular changes remains poorly known, particularly in plants. Here, we have introduced a novel method that integrates phylogenomic, comparative genomic, and ecological niche modeling analyses to investigate the rate of molecular evolution of Eupteleaceae, a Cretaceous relict angiosperm family endemic to East Asia. We assembled a high-quality chromosome-level nuclear genome, and the chloroplast and mitochondrial genomes of a member of Eupteleaceae (Euptelea pleiosperma). Our results show that Eupteleaceae is most basal in Ranunculales, the earliest-diverging order in eudicots, and shares an ancient whole-genome duplication event with the other Ranunculales. We document that Eupteleaceae has the slowest rate of molecular changes in the observed angiosperms. The unusually low rate of molecular evolution of Eupteleaceae across all three independent inherited genomes and genes within each of the three genomes is in association with its conserved genome architecture, ancestral woody habit, and conserved niche requirements. Our findings reveal the evolution and adaptation of living fossil plants through large-scale environmental change and also provide new insights into early eudicot diversification.

DOI: 10.1007/s11427-023-2448-x

Source: https://link.springer.com/article/10.1007/s11427-023-2448-x