Whole-genome analysis reveals molecular innovations and evolutionary transitions in chromalveolate species
Whole-genome analysis reveals molecular innovations and evolutionary transitions in chromalveolate species
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DOI：
10.1073/pnas.0712248105
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发表时间：
2008-03-04
影响因子：
11.1
通讯作者：
Van de Peer, Yves
中科院分区：
文献类型：
--
作者：
Martens, Cindy;Vandepoele, Klaas;Van de Peer, Yves
chromalveolates形成了一个高度多样化和迷人的生物组合，从专性寄生虫如疟原虫到自由生活的纤毛虫和藻类如海带，硅藻和甲藻。在这个单系群中的许多物种具有重要的医学、生态和经济意义。然而，它们的基因组进化远不如高等植物、动物或真菌的基因组进化研究得好。在目前的研究中，我们已经分析和比较了12个chromalveolate物种的全序列信息，并提供了一个详细的图片在不同的血统的基因丢失和基因获得。正如预期的那样，许多基因丢失和获得事件可以直接与所研究的生物体的生活方式和特定适应相关。例如，在专性细胞内Apicomplexa中，我们观察到在氨基酸，碳水化合物和脂质代谢等一般基本过程中发挥作用的基因的大量丢失，反映了自由生活向专性细胞内生活方式的转变。相比之下，许多基因家族显示出物种特异性扩增，例如植物病原体卵菌疫霉属中的那些，其参与降解植物细胞壁多糖以促进病原体入侵过程。一般来说，染色体组在基因组结构和进化上，以及在通过复制或水平基因转移丢失或获得的基因数量上，表现出巨大的差异。
The chromalveolates form a highly diverse and fascinating assemblage of organisms, ranging from obligatory parasites such as Plasmodium to free-living ciliates and algae such as kelps, diatoms, and dinoflagellates. Many of the species in this monophyletic grouping are of major medical, ecological, and economical importance. Nevertheless, their genome evolution is much less well studied than that of higher plants, animals, or fungi. In the current study, we have analyzed and compared 12 chromalveolate species for which whole-sequence information is available and provide a detailed picture on gene loss and gene gain in the different lineages. As expected, many gene loss and gain events can be directly correlated with the lifestyle and specific adaptations of the organisms studied. For instance, in the obligate intracellular Apicomplexa we observed massive loss of genes that play a role in general basic processes such as amino acid, carbohydrate, and lipid metabolism, reflecting the transition of a free-living to an obligate intracellular lifestyle. In contrast, many gene families show species-specific expansions, such as those in the plant pathogen oomycete Phytophthora that are involved in degrading the plant cell wall polysaccharides to facilitate the pathogen invasion process. In general, chromalveolates show a tremendous difference in genome structure and evolution and in the number of genes they have lost or gained either through duplication or horizontal gene transfer.