病毒介导的海洋球石藻(Coccolithophores)鞘脂类代谢调控

海洋球石藻(Coccolithophores)是一种全球广泛分布且具有重要生态功能的真核浮游植物,有些种类是大洋和近岸常见的赤潮种。自然海域中,病毒感染是导致球石藻死亡和赤潮消亡的一个关键因素。基于一株海洋球石藻Emiliania huxleyi及其特异性裂解病毒全基因组测序注释的结果,研究者们发现病毒可能通过基因横向转移从宿主基因组中获取了一系列与鞘脂类代谢相关的关键酶基因,进而在一定程度上掌控了宿主鞘脂类代谢,大量合成、积累病毒性鞘脂类物质,并最终诱导宿主细胞以凋亡的形式死亡。因此,病毒介导的宿主鞘脂类代谢在调节病毒与宿主间相互作用中具有重要意义。本文着重综述海洋球石藻病毒与宿主间的基因横向转移、病毒介导的宿主鞘脂类代谢特点及其生态学意义,以期深入了解海洋球石藻病毒与宿主间复杂的相互作用关系。

Virus mediated sphingolipid metabolic regulation in marine coccolithophores

Coccolithophores are one of the most widespread groups of unicellular eukaryotic marine phytoplankton and play crucial roles in marine ecosystem. Some coccolithophores are bloom-forming species in ocean and offshore. In natural marine ecosystem, virus infection is one of the major causes of natural mortality and the demise of large oceanic blooms formed by this group. Integrated analysis based on the genomic sequences of Emiliania huxleyi, a major species of coccolithophores and its specific lytic virus Emilliania huxleyi virus (EhV), has implied that EhV obtained a series of key enzyme genes involved in sphingolipids metabolism from host genome by horizontal gene transfer. In some ways, EhV manipulates sphingolipids metabolism of host and triggers biosynthesis and accumulation of infection-derived sphingolipids, resulting in the apoptosis of host cell. Thus, virus-mediated host sphingolipids metabolism plays an important role in virus-host interaction. Here, we describe the horizontal gene transfer between EhV and host, the characteristics of virus-mediated host sphingolipids metabolism and the ecological significance in order to understand the complicated interaction between E. huxleyi virus and its host.