Chan Cheong Xin, Bhattacharya Debashish, Reyes-Prieto Adrian
Mob Genet Elements. 2012 Mar 1;2(2):101-105. doi: 10.4161/mge.20110.
The evolution of microbial eukaryotes, in particular of photosynthetic lineages, is complicated by multiple instances of endosymbiotic and horizontal gene transfer (E/HGT) resulting from plastid origin(s). Our recent analysis of diatom membrane transporters provides evidence of red and/or green algal origins of 172 of the genes encoding these proteins (ca. 25% of the examined phylogenies), with the majority putatively derived from green algae. These data suggest that E/HGT has been an important driver of evolutionary innovation among diatoms (and likely other stramenopiles), and lend further support to the hypothesis of an ancient, cryptic green algal endosymbiosis in "chromalveolate" lineages. Here, we discuss the implications of our findings on the understanding of eukaryote evolution and inference of the tree of life.
微生物真核生物的进化，尤其是光合谱系的进化，因质体起源导致的多次内共生和水平基因转移（E/HGT）事件而变得复杂。我们最近对硅藻膜转运蛋白的分析表明，编码这些蛋白的172个基因（约占所研究系统发育的25%）起源于红藻和/或绿藻，其中大多数可能源自绿藻。这些数据表明，E/HGT一直是硅藻（可能还有其他不等鞭毛类）进化创新的重要驱动力，并进一步支持了“色藻界”谱系中存在古老、隐秘的绿藻内共生现象这一假说。在此，我们讨论了我们的研究结果对理解真核生物进化和推断生命之树的意义。
