Mesostigma viride Genome and Transcriptome Provide Insights into the Origin and Evolution of Streptophyta

First author: Zhe Liang; Affiliations: National University of Singapore (新加坡国立大学): Singapore, Singapore

Corresponding author: Hao Yu

The Streptophyta include unicellular and multicellular charophyte green algae and land plants. Colonization of the terrestrial habitat by land plants is a major evolutionary event that has transformed the planet. So far, lack of genome information on unicellular charophyte algae hinders the understanding of the origin and the evolution from unicellular to multicellular life in Streptophyta. This work reports the high‐quality reference genome and transcriptome of Mesostigma viride, a single‐celled charophyte alga with a position at the base of Streptophyta. There are abundant segmental duplications and transposable elements in M. viride, which contribute to a relatively large genome with high gene content compared to other algae and early diverging land plants. This work identifies the origin of genetic tools that multicellular Streptophyta have inherited and key genetic innovations required for the evolution of land plants from unicellular aquatic ancestors. The findings shed light on the age‐old questions of the evolution of multicellularity and the origin of land plants.

链形植物（Streptophyta）包括单细胞和多细胞的轮藻类绿藻和陆地植物。陆地植物殖民陆地生境是一个重要的演化事件，此后彻底改变了我们星球的面貌。目前为止，由于缺少单细胞轮藻类绿藻的基因组信息严重阻遏了对于链形植物起源以及单细胞向多细胞生物演化的理解。本文中，作者报道了一个处于链形植物基部位置的单细胞轮藻Mesostigma viride的高质量参考基因组以及转录组。在M. viride基因组中存在大量的片段化重复和转座元件，从而导致了其相比于其它藻类植物以及早期分化的陆地植物基因组更大，基因含量更密集。本文的工作鉴定了多细胞链形植物所继承的遗传成分起源以及从水生单细胞生物演化成陆地植物所需的关键遗传创新。这些发现为多细胞植物的演化以及陆地植物的起源提供了新的视野。

通讯：Hao Yu (http://www.dbs.nus.edu.sg/staff/yuhao.htm)

研究方向：拟南芥中控制生殖发育和激素信号转导的基因调控网络。

doi: https://doi.org/10.1002/advs.201901850

Journal: Advance Science

Published date: October 24, 2019