英国布里斯托大学Philip C. J. Donoghue小组宣布他们提出了有年代标记的基因重复阐明了真核生物的进化过程。相关论文发表在2025年12月3日出版的《自然》杂志上。

在这里，研究组以一个宽松的分子时钟为主题，表明真核发生的过程跨越了中太古宙到古元古代晚期。在这些限制条件下，该研究团队确定了这些基因复制的时间，揭示了真核宿主细胞在线粒体内共生之前已经具有复杂的细胞特征，包括复杂的细胞骨架、膜运输、内膜、吞噬机制和核核，这些都发生在30亿至22.5亿年前，之后线粒体内共生发生。他们的结果使他们能够拒绝真核发生的线粒体早期情景，而支持一个复杂的太古宙晚期线粒体序列来组装真核生物的特征。他们对复杂的古细菌宿主细胞的推断，与对海洋共生的适应性好处的假设是一致的，因为海洋在超过10亿年的时间里基本上是缺氧的。

研究人员表示，真核生物的起源是生命史上一个形成性的但却鲜为人知的事件。目前真核发生的假设主要不同于线粒体内共生的时间，相对于其他真核生物的获得。在这些假设之间进行区分是具有挑战性的，因为在真核发生过程中没有代表中间步骤的活的谱系。然而，许多真核细胞的功能取决于真核发生过程中复制事件产生的基因。因此，这些复制的时间尺度可以为真核细胞进化组装的步骤序列提供见解。

附：英文原文

Title: Dated gene duplications elucidate the evolutionary assembly of eukaryotes

Author: Kay, Christopher J., Spang, Anja, Szllsi, Gergely J., Pisani, Davide, Williams, Tom A., Donoghue, Philip C. J.

Issue&Volume: 2025-12-03

Abstract: The origin of eukaryotes was a formative but poorly understood event in the history of life. Current hypotheses of eukaryogenesis differ principally in the timing of mitochondrial endosymbiosis relative to the acquisition of other eukaryote novelties1. Discriminating among these hypotheses has been challenging, because there are no living lineages representative of intermediate steps within eukaryogenesis. However, many eukaryotic cell functions are contingent on genes that emerged from duplication events during eukaryogenesis2,3. Consequently, the timescale of these duplications can provide insights into the sequence of steps in the evolutionary assembly of the eukaryotic cell. Here we show, using a relaxed molecular clock4, that the process of eukaryogenesis spanned the Mesoarchaean to late Palaeoproterozoic eras. Within these constraints, we dated the timing of these gene duplications, revealing that the eukaryotic host cell already had complex cellular features before mitochondrial endosymbiosis, including an elaborated cytoskeleton, membrane trafficking, endomembrane, phagocytotic machinery and a nucleus, all between 3.0 and 2.25 billion years ago, after which mitochondrial endosymbiosis occurred. Our results enable us to reject mitochondrion-early scenarios of eukaryogenesis5, instead supporting a complexified-archaean, late-mitochondrion sequence for the assembly of eukaryote characteristics. Our inference of a complex archaeal host cell is compatible with hypotheses on the adaptive benefits of syntrophy6,7 in oceans that would have remained largely anoxic for more than a billion years8,9.

DOI: 10.1038/s41586-025-09808-z

Source: https://www.nature.com/articles/s41586-025-09808-z