Gene duplication accelerates the pace of protein gain and loss from plant organelles
Gene duplication accelerates the pace of protein gain and loss from plant organelles
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基因复制加速了植物细胞器蛋白质获得和损失的速度
DOI：
10.1101/415125
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Costello R
中科院分区：
文献类型：
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作者：
Costello R
介绍性段落真核细胞的一个标志是将细胞内过程划分为专门的膜结合区室，称为细胞器。植物细胞含有几种这样的细胞器，包括细胞核、叶绿体、线粒体、过氧化物酶体、高尔基体、内质网和液泡。细胞器的生物发生和功能依赖于众多核编码蛋白的协同作用，这些蛋白必须从它们产生的细胞质（或内质网）中输入。使用系统发育学方法与祖先状态估计相结合，我们发现植物细胞器蛋白质组含量的变化率与分子序列进化的速度成正比，使得叶绿体和线粒体的蛋白质组每百万年损失或增加约3.2个蛋白质。我们表明，蛋白质靶向的这些变化主要发生在具有调节功能而不是代谢功能的基因中，因此改变调节能力而不是代谢功能一直是植物细胞器进化的主题。最后，我们发现基因复制事件后蛋白质靶向的获得和丢失发生率更高，这表明基因和基因组复制是细胞器进化的关键促进因素。
Introductory paragraphA hallmark of eukaryotic cells is the compartmentalisation of intracellular processes into specialised membrane-bound compartments known as organelles. Plant cells contain several such organelles including the nucleus, chloroplast, mitochondrion, peroxisome, golgi, endoplasmic reticulum and vacuole. Organelle biogenesis and function is dependent on the concerted action of numerous nuclear-encoded proteins which must be imported from the cytosol (or endoplasmic reticulum) where they are made. Using phylogenomic approaches coupled to ancestral state estimation we show that the rate of change in plant organellar proteome content is proportional to the rate of molecular sequence evolution such that the proteomes of chloroplasts and mitochondria lose or gain ~3.2 proteins per million years. We show that these changes in protein targeting have predominantly occurred in genes with regulatory rather than metabolic functions, and thus altered regulatory capacity rather than metabolic function has been the major theme of plant organellar evolution. Finally we show gain and loss of protein targeting occurs at a higher rate following gene duplication events, revealing that gene and genome duplication are a key facilitator of organelle evolution.