Evolution of UhpC-type hexose-phosphate transporters in dinoflagellates.
Evolution of UhpC-type hexose-phosphate transporters in dinoflagellates.
复制标题
甲藻中 UhpC 型磷酸己糖转运蛋白的进化。
DOI：
10.1111/pre.12164
复制
发表时间：
2017
影响因子：
1.5
通讯作者：
Ken-ichiro Ishida
中科院分区：
文献类型：
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作者：
Yoshihisa Hirakawa;Takuro Nakayama;Nadine Keilert;Ken-ichiro Ishida
古质体的初级质体是单个蓝细菌内共生体的后代，而许多其他藻类通过对初级质体承载藻类的几个平行的内共生摄取获得了复杂的质体，即所谓的次级质体。在初级和次级内共生过程中，内共生体整合到其宿主中，需要建立代谢物、无机离子和蛋白质穿过质体包膜膜的运输机制。作为从初级质体中输出光合产物的潜在蛋白质，细菌 UhpC 型磷酸己糖转运蛋白的同源物在古质体的藻类成员中被发现。有人提出，质体 UhpC 型转运蛋白是通过与衣原体密切相关的细菌谱系的横向基因转移而在古质体的共同祖先中获得的。然而，次生质体携带生物是否具有 UhpC 型转运蛋白仍不清楚。在本研究中，我们利用现有的基因组和转录组数据研究了不同藻类中 UhpC 的同源基因。我们的同源性调查和系统发育分析表明，只有甲藻拥有源自古质体谱系的 UhpC 型转运蛋白，而许多其他次生质体生物体则缺乏它们。由于存在其他糖磷酸转运蛋白家族，UhpC 型转运蛋白在许多次生质体中可能不是必需的。
Primary plastids of the group Archaeplastida are descendants of a single cyanobacterial endosymbiont, while many other algal groups have obtained complex plastids, the so‐called secondary plastids, via several parallel endosymbiotic uptakes of primary plastid‐bearing algae. Integration of the endosymbiont into its host during primary and secondary endosymbiosis necessitated the establishment of transport mechanisms for metabolites, inorganic ions, and proteins across plastid envelope membranes. As a potential protein for exporting photosynthates out of primary plastids, homologs of bacterial UhpC‐type hexose‐phosphate transporters were found in algal members of the Archaeplastida. It has been proposed that plastidic UhpC‐type transporters have been acquired in the common ancestor of Archaeplastida by the lateral gene transfer from a bacterial lineage closely related to Chlamydiae. However, it remains unknown whether secondary plastid‐bearing organisms possess UhpC‐type transporters. In the present study, we investigated homologous genes of UhpC in diverse algae using available genome and transcriptome data. Our homology survey and phylogenetic analyses revealed that only dinoflagellates possess UhpC‐type transporters derived from an archaeplastidal lineage, whereas many other secondary plastid‐bearing organisms lack them. It is possible that UhpC‐type transporters are not essential in many secondary plastids because of the existence of other families of sugar phosphate transporters.