ERAD components in organisms with complex red plastids suggest recruitment of a preexisting protein transport pathway for the periplastid membrane.
ERAD components in organisms with complex red plastids suggest recruitment of a preexisting protein transport pathway for the periplastid membrane.
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具有复杂红色质体的生物体中的ERAD成分表明，募集了Periplastid膜的蛋白质转运途径。
DOI：
10.1093/gbe/evq074
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发表时间：
2011
影响因子：
3.3
通讯作者：
Maier UG
中科院分区：
文献类型：
--
作者：
Felsner G;Sommer MS;Gruenheit N;Hempel F;Moog D;Zauner S;Martin W;Maier UG
隐芽植物、附着植物和异鞭毛植物的质体被四层膜包围，反映了这些质体通过次生内共生的起源。它们与顶复门（apicomplexans）共享这一特征，顶复门是一种泡状动物，其质体被认为源于相同的次级共生事件，因此形成了一个系统发育分支，即chromalveolates。在海洋生态系统中，铬铁矿是最重要的真核生物初级生产力的贡献者。蛋白质通过其四种质体膜的转运机制仍然知之甚少。内质网相关的降解（ERAD）机制的组成部分，部分编码的次生共生体（核态）的简化基因组的隐芽植物，有牵连的蛋白质运输跨第二最外层质体膜。在这里，我们表明，附着体Emiliania huxleyi，像隐藻，strapoliiles，apicomplexans，拥有一个核编码的共生体特异性ERAD机器（SELMA，共生体特异性ERAD样机器）除了主机ERAD系统，与靶向信号，能够直接绿色荧光蛋白或黄色荧光蛋白的预测细胞定位在转化细胞的strapoliile三角褐指藻。重复ERAD因子的系统发育显示，所有SELMA组件追溯到红藻起源。与此相反，隐芽植物和附着植物的宿主拷贝与绿色谱系相关联，排除了层生菌和泡状菌。虽然所有的chromalveolates与四个膜结合质体拥有SELMA系统，这显然没有出现在一个单一的内共生事件。因此，我们的数据不支持chromalveolate假说。
The plastids of cryptophytes, haptophytes, and heterokontophytes (stramenopiles) (together once known as chromists) are surrounded by four membranes, reflecting the origin of these plastids through secondary endosymbiosis. They share this trait with apicomplexans, which are alveolates, the plastids of which have been suggested to stem from the same secondary symbiotic event and therefore form a phylogenetic clade, the chromalveolates. The chromists are quantitatively the most important eukaryotic contributors to primary production in marine ecosystems. The mechanisms of protein import across their four plastid membranes are still poorly understood. Components of an endoplasmic reticulum-associated degradation (ERAD) machinery in cryptophytes, partially encoded by the reduced genome of the secondary symbiont (the nucleomorph), are implicated in protein transport across the second outermost plastid membrane. Here, we show that the haptophyte Emiliania huxleyi, like cryptophytes, stramenopiles, and apicomplexans, possesses a nuclear-encoded symbiont-specific ERAD machinery (SELMA, symbiont-specific ERAD-like machinery) in addition to the host ERAD system, with targeting signals that are able to direct green fluorescent protein or yellow fluorescent protein to the predicted cellular localization in transformed cells of the stramenopile Phaeodactylum tricornutum. Phylogenies of the duplicated ERAD factors reveal that all SELMA components trace back to a red algal origin. In contrast, the host copies of cryptophytes and haptophytes associate with the green lineage to the exclusion of stramenopiles and alveolates. Although all chromalveolates with four membrane-bound plastids possess the SELMA system, this has apparently not arisen in a single endosymbiotic event. Thus, our data do not support the chromalveolate hypothesis.
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影响因子：
3.3
作者：
Cavalier-Smith, Thomas
通讯作者：
Cavalier-Smith, Thomas
影响因子：
56.9
作者：
Armbrust, EV;Berges, JA;Rokhsar, DS
通讯作者：
Rokhsar, DS
影响因子：
10.7
作者：
Bryant, D;Moulton, V
通讯作者：
Moulton, V
DOI：
10.1099/ijs.0.63216-0
发表时间：
2005-01-01
影响因子：
2.8
作者：
Harper, JT;Waanders, E;Keeling, PJ
通讯作者：
Keeling, PJ
影响因子：
4.8
作者：
Agrawal, Swati;van Dooren, Giel G.;Striepen, Boris
通讯作者：
Striepen, Boris