Microbial eukaryotes have adapted to hypoxia by horizontal acquisitions of a gene involved in rhodoquinone biosynthesis.
Microbial eukaryotes have adapted to hypoxia by horizontal acquisitions of a gene involved in rhodoquinone biosynthesis.
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DOI：
10.7554/elife.34292
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发表时间：
2018-04-26
期刊：
影响因子：
7.7
通讯作者：
Roger AJ
中科院分区：
文献类型：
--
作者：
Stairs CW;Eme L;Muñoz-Gómez SA;Cohen A;Dellaire G;Shepherd JN;Fawcett JP;Roger AJ
在缺氧条件下，一些生物体使用仅由复合物I和II（CII）组成的电子传递链来产生ATP产生所必需的质子梯度。在这些情况下，CII作为富马酸还原酶起作用，其从低电子电位的醌醇，即对苯二酚（RQ）接受电子。为了阐明真核生物中RQ介导的延胡索酸还原的起源，我们研究了编码RQ生物合成酶的基因rquA的起源和功能。RquA在适应缺氧的真核生物和细菌中分布不均。系统发育分析表明，rquA从细菌到真核生物的横向基因转移（LGT）至少发生了两次，并且该基因在原生生物中多次转移。我们表明，RquA的功能，在厌氧原生生物Pygsuia的相关的细胞器中，并与RQ的存在。这些分析揭示了基因转移在线粒体适应缺氧的进化重塑中的作用。
Under hypoxic conditions, some organisms use an electron transport chain consisting of only complex I and II (CII) to generate the proton gradient essential for ATP production. In these cases, CII functions as a fumarate reductase that accepts electrons from a low electron potential quinol, rhodoquinol (RQ). To clarify the origins of RQ-mediated fumarate reduction in eukaryotes, we investigated the origin and function of rquA, a gene encoding an RQ biosynthetic enzyme. RquA is very patchily distributed across eukaryotes and bacteria adapted to hypoxia. Phylogenetic analyses suggest lateral gene transfer (LGT) of rquA from bacteria to eukaryotes occurred at least twice and the gene was transferred multiple times amongst protists. We demonstrate that RquA functions in the mitochondrion-related organelles of the anaerobic protist Pygsuia and is correlated with the presence of RQ. These analyses reveal the role of gene transfer in the evolutionary remodeling of mitochondria in adaptation to hypoxia.