The establishment of the photosynthetic organelle (plastid) in eukaryotes and the diversification of algae and plants were landmark evolutionary events because these taxa form the base of the food chain for many ecosystems on our planet. The plastid originated via a putative single, ancient primary endosymbiosis in which a heterotrophic protist engulfed and retained a cyanobacterium in its cytoplasm. Once successfully established, this plastid spread into other protist lineages through eukaryote-eukaryote (secondary and tertiary) endosymbioses. This process of serial cell capture and enslavement explains the diversity of photosynthetic eukaryotes. Recent genomic and phylogenomic approaches have significantly clarified plastid genome evolution, the movement of endosymbiont genes to the "host" nuclear genome (endosymbiotic gene transfer), and plastid spread throughout the eukaryotic tree of life. Here we review these aspects of plastid evolution with a focus on understanding early events in plastid endosymbiosis.

中文翻译：

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藻类和植物中质体的起源和建立。

真核生物中光合作用细胞器（质体）的建立以及藻类和植物的多样化是具有里程碑意义的进化事件，因为这些分类群构成了地球上许多生态系统食物链的基础。质体起源于一个假定的单一的古老原发性共生体，其中异养原生生物吞噬并在细胞质中保留了蓝细菌。一旦成功建立，该质体就会​​通过真核生物-真核生物（次生和三次）内共生酶传播到其他原生生物谱系中。连续细胞捕获和奴役的过程解释了光合真核生物的多样性。最近的基因组学和系统基因组学方法已显着阐明了质体基因组进化，共生体基因向“宿主”核基因组的移动（内共生基因转移），和质体遍布真核生物的生命之树。在这里，我们回顾了质体进化的这些方面，重点是了解质体内共生的早期事件。