Ben-Yosef Michael, Zaada Doron S Y, Dudaniec Rachael Y, Pasternak Zohar, Jurkevitch Edouard, Smith Renee J, Causton Charlotte E, Lincango Maria Piedad, Tobe Shanan S, Mitchell James G, Kleindorfer Sonia, Yuval Boaz
Department of Entomology, Faculty of Agriculture Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel.
Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia.
Mol Ecol. 2017 Sep;26(18):4644-4656. doi: 10.1111/mec.14219. Epub 2017 Aug 2.
The composition and diversity of bacteria forming the microbiome of parasitic organisms have implications for differential host pathogenicity and host-parasite co-evolutionary interactions. The microbiome of pathogens can therefore have consequences that are relevant for managing disease prevalence and impact on affected hosts. Here, we investigate the microbiome of an invasive parasitic fly Philornis downsi, recently introduced to the Galápagos Islands, where it poses extinction threat to Darwin's finches and other land birds. Larvae infest nests of Darwin's finches and consume blood and tissue of developing nestlings, and have severe mortality impacts. Using 16s rRNA sequencing data, we characterize the bacterial microbiota associated with P. downsi adults and larvae sourced from four finch host species, inhabiting two islands and representing two ecologically distinct groups. We show that larval and adult microbiomes are dominated by the phyla Proteobacteria and Firmicutes, which significantly differ between life stages in their distributions. Additionally, bacterial community structure significantly differed between larvae retrieved from strictly insectivorous warbler finches (Certhidea olivacea) and those parasitizing hosts with broader dietary preferences (ground and tree finches, Geospiza and Camarhynchus spp., respectively). Finally, we found no spatial effects on the larval microbiome, as larvae feeding on the same host (ground finches) harboured similar microbiomes across islands. Our results suggest that the microbiome of P. downsi changes during its development, according to dietary composition or nutritional needs, and is significantly affected by host-related factors during the larval stage. Unravelling the ecological significance of bacteria for this parasite will contribute to the development of novel, effective control strategies.
构成寄生生物微生物组的细菌的组成和多样性，对宿主致病性差异以及宿主 - 寄生虫的共同进化相互作用具有重要意义。因此，病原体的微生物组可能会对疾病流行率的控制以及对受影响宿主的影响产生相关后果。在此，我们研究了一种入侵性寄生蝇——近来被引入加拉帕戈斯群岛的南美长尾雀蝇（Philornis downsi）的微生物组，它对达尔文雀和其他陆地鸟类构成了灭绝威胁。其幼虫侵扰达尔文雀的巢穴，并取食发育中雏鸟的血液和组织，造成严重的死亡影响。利用16s rRNA测序数据，我们对源自四个雀类宿主物种、栖息于两个岛屿且代表两个生态上不同群体的南美长尾雀蝇成虫和幼虫相关的细菌微生物群进行了特征描述。我们发现，幼虫和成虫的微生物组以变形菌门和厚壁菌门为主，它们在不同生命阶段的分布存在显著差异。此外，从严格食虫的莺雀（Certhidea olivacea）体内获取的幼虫与寄生于食性更广的宿主（分别为地雀和树雀，Geospiza和Camarhynchus spp.）的幼虫相比，细菌群落结构存在显著差异。最后，我们发现幼虫的微生物组不存在空间效应，因为以同一宿主（地雀）为食的幼虫在不同岛屿上具有相似的微生物组。我们的研究结果表明，南美长尾雀蝇的微生物组在其发育过程中会根据饮食组成或营养需求发生变化，并且在幼虫阶段受到宿主相关因素的显著影响。揭示细菌对这种寄生虫的生态意义，将有助于开发新的有效控制策略。
