Gao Zhi Wei, Wang Long
Kuang Yaming Honors School, Nanjing University, Nanjing210023, China.
State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, China.
Yi Chuan. 2020 Oct 20;42(10):929-948. doi: 10.16288/j.yczz.20-107.
Knowledge of the origin of eukaryotes is key to broadening our understanding of the eukaryotic genome and the relationship among internal structures within a eukaryotic cell. Since the discovery of archaea in 1977 and the proposal of three-domain tree of life by the American microbiologist Carl Woese, the intimate relationship in evolution between eukaryotes and archaea has been demonstrated by considerable experiments and analyses. From the beginning of the 21st century, with the development of phylogenetic methods and the discovery of new archaeal phyla more related to eukaryotes, increasing evidence has shown that Eukarya and Archaea should be merged into one domain, leading to a two-domain tree of life. Nowadays, the Asgard superphylum discovered via metagenomic analysis is regarded as the closest prokaryotes to eukaryotes. Nevertheless, several key questions are still under debate, such as what the ancestors of the eukaryotes were and when mitochondria emerged. Here, we review the current research progress regarding the changes of the tree of life and the detailed eukaryotic evolutionary mechanism. We show that the recent findings have greatly improved our knowledge on the origin of eukaryotes, which will pave the way for future studies.
了解真核生物的起源是拓宽我们对真核生物基因组以及真核细胞内部结构之间关系理解的关键。自1977年古菌被发现以及美国微生物学家卡尔·沃斯提出三域生命树以来，大量实验和分析已证明真核生物与古菌在进化上的密切关系。从21世纪初开始，随着系统发育方法的发展以及与真核生物关系更为密切的新古菌门的发现，越来越多的证据表明真核生物域和古菌域应合并为一个域，从而形成两域生命树。如今，通过宏基因组分析发现的阿斯加德超群被认为是与真核生物最接近的原核生物。然而，仍有几个关键问题存在争议，比如真核生物的祖先是什么以及线粒体何时出现。在此，我们综述了关于生命树变化及详细真核生物进化机制的当前研究进展。我们表明，最近的研究结果极大地增进了我们对真核生物起源的认识，这将为未来的研究铺平道路。
