Table_6_Three feminizing Wolbachia strains in a single host species: comparative genomics paves the way for identifying sex reversal factors.XLSX

IntroductionEndosymbiotic bacteria in the genus Wolbachia have evolved numerous strategies for manipulating host reproduction in order to promote their own transmission. This includes the feminization of males into functional females, a well-studied phenotype in the isopod Armadillidium vulgare. Despite an early description of this phenotype in isopods and the development of an evolutionary model of host sex determination in the presence of Wolbachia, the underlying genetic mechanisms remain elusive.MethodsHere we present the first complete genomes of the three feminizing Wolbachia (wVulC, wVulP, and wVulM) known to date in A. vulgare. These genomes, belonging to Wolbachia B supergroup, contain a large number of mobile elements such as WO prophages with eukaryotic association modules. Taking advantage of these data and those of another Wolbachia-derived feminizing factor integrated into the host genome (f element), we used a comparative genomics approach to identify putative feminizing factors.ResultsThis strategy has enabled us to identify three prophage-associated genes secreted by the Type IV Secretion System: one ankyrin repeat domain-containing protein, one helix-turn-helix transcriptional regulator and one hypothetical protein. In addition, a latrotoxin-related protein, associated with phage relic genes, was shared by all three genomes and the f element.ConclusionThese putative feminization-inducing proteins shared canonical interaction features with eukaryotic proteins. These results pave the way for further research into the underlying functional interactions.

引言：属于沃尔巴西亚属的共生细菌已演化出多种策略以操纵宿主的繁殖，从而促进自身的传播。这包括将雄性转变为功能性雌性，这是在等足类动物盔甲虾（Armadillidium vulgare）中研究颇深的表型。尽管在等足类动物中早已描述了这一表型，并在沃尔巴西亚属存在的情况下建立了宿主性别决定的进化模型，但其背后的遗传机制仍难以捉摸。方法：在此，我们首次呈现了已知在盔甲虾中三种具有雌性化作用的沃尔巴西亚属细菌（wVulC、wVulP和wVulM）的完整基因组。这些基因组属于沃尔巴西亚属B超群，其中包含大量可移动元件，如与真核生物关联模块的WO前噬菌体。利用这些数据以及整合到宿主基因组中的另一种沃尔巴西亚属衍生雌性化因子（f元件）的数据，我们采用比较基因组学方法来鉴定潜在的雌性化因子。结果：此策略使我们能够鉴定出由IV型分泌系统分泌的三种与噬菌体相关基因：一种含锚蛋白重复结构域蛋白、一种螺旋-转角-螺旋转录调控蛋白以及一种假定的蛋白。此外，一种与噬菌体遗迹基因相关的拉托毒素相关蛋白，为所有三种基因组以及f元件所共有。结论：这些潜在的雌性化诱导蛋白与真核生物蛋白共享了经典的相互作用特征。这些结果为深入探究其背后的功能相互作用铺平了道路。