Why It Is Time to Look Beyond Algal Genes in Photosynthetic Slugs.
Why It Is Time to Look Beyond Algal Genes in Photosynthetic Slugs.
复制标题
DOI：
10.1093/gbe/evv173
复制
发表时间：
2015-08-29
影响因子：
3.3
通讯作者：
Gould SB
中科院分区：
文献类型：
--
作者：
Rauch C;Vries Jd;Rommel S;Rose LE;Woehle C;Christa G;Laetz EM;Wägele H;Tielens AG;Nickelsen J;Schumann T;Jahns P;Gould SB
真核细胞器依靠核基因来维持其生化完整性。所有真核生物中的线粒体和植物和藻类中的质体都是如此。那么，在没有编码绝大多数细胞器蛋白的藻核的情况下，被一些棘舌海蛞蝓隔离的藻体是如何在动物的消化腺细胞中存活下来的呢？近二十年来，从藻类到鼻涕虫的横向基因转移（LGT）似乎提供了一个解决方案，但是RNA-seq分析，后来由鼻涕虫DNA的基因组测序支持，未能找到任何证据证明这种LGT事件。然而，孤立的报道继续发表，并很容易被大众媒体和社交媒体讨论，这使得LGT的数据及其对kleptoplast寿命的支持显得有争议。然而，当我们冷静地审视所使用的方法时，我们意识到对结果的解释是有必要谨慎的。没有证据表明海蛞蝓的窃听器成形术与LGT事件有关。基于我们对胚胎质体光系统维持的了解，我们假设窃听器依赖于核基因。然而，研究表明，从本质上讲，一些分离的藻类质体比陆地植物的质体更健壮。绿海蛞蝓眼睑成形术的进化涉及许多有希望的和未被探索的现象，但没有证据表明这些现象需要藻类来源的蛞蝓基因的表达。
Eukaryotic organelles depend on nuclear genes to perpetuate their biochemical integrity. This is true for mitochondria in all eukaryotes and plastids in plants and algae. Then how do kleptoplasts, plastids that are sequestered by some sacoglossan sea slugs, survive in the animals’ digestive gland cells in the absence of the algal nucleus encoding the vast majority of organellar proteins? For almost two decades, lateral gene transfer (LGT) from algae to slugs appeared to offer a solution, but RNA-seq analysis, later supported by genome sequencing of slug DNA, failed to find any evidence for such LGT events. Yet, isolated reports continue to be published and are readily discussed by the popular press and social media, making the data on LGT and its support for kleptoplast longevity appear controversial. However, when we take a sober look at the methods used, we realize that caution is warranted in how the results are interpreted. There is no evidence that the evolution of kleptoplasty in sea slugs involves LGT events. Based on what we know about photosystem maintenance in embryophyte plastids, we assume kleptoplasts depend on nuclear genes. However, studies have shown that some isolated algal plastids are, by nature, more robust than those of land plants. The evolution of kleptoplasty in green sea slugs involves many promising and unexplored phenomena, but there is no evidence that any of these require the expression of slug genes of algal origin.