Multiple independent origins of apicomplexan-like parasites

Using single-cell genomics and transcriptomics from diverse uncultivated parasites, we find that two genera classified as apicomplexan, Piridium and Platyproteum, form distinct lineages in phylogenomic analyses. Both retain cryptic plastids with genomic and metabolic features convergent with apicomplexans. These findings suggest a predilection in this lineage for both the loss of photosynthesis and a transition to a morphologically similar parasitic lifestyle, resulting in multiple lineages of highly convergent animal parasites.

我们针对多种未培养寄生虫开展单细胞基因组学（single-cell genomics）与转录组学（transcriptomics）研究，发现被归类为顶复门寄生虫（apicomplexan）的两个属——Piridium和Platyproteum——在系统发育基因组学分析（phylogenomic analyses）中形成了独立的演化支。二者均保留了具有与顶复门寄生虫趋同的基因组与代谢特征的隐秘质体（cryptic plastids）。上述研究结果表明，该演化支在演化过程中倾向于同时丧失光合作用，并转型为形态相似的寄生生活方式，最终形成了多个高度趋同的动物寄生虫类群。