State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China.
Integr Zool. 2021 May;16(3):313-323. doi: 10.1111/1749-4877.12528. Epub 2021 Mar 25.
Insects' intestinal microbes have profound effects on the host's physiological traits, which can impact their physiology at both the local (gut) and systemic (body) levels. Nevertheless, the molecular mechanisms underlying host-microbiota interactions, especially in non-model insects, remain elusive. Recently, tissue-specific transcriptomic analysis has been highlighted as a robust tool in studying host-microbe interactions. Plagiodera versicolora is a worldwide leaf-eating pest that primarily feeds on willows and poplar. The interplay between gut microflora and this host beetle has yet to be studied. Herein, we investigate the effects of the gut microbiota on the body mass of P. versicolora larvae, compare the nutrition status of larvae in absence and presence of gut microbiota, and profile gut bacterial loads throughout its developmental larval stages. We then perform comparative transcriptomic analysis of gut and body tissues in axenic and non-axenic larvae. Finally, we confirm the expression patterns of representative genes in nutritional metabolism and immunity. Results show that weight growth is retarded in conventional larvae, with a concomitant increase of total bacterial load by the 5 development day, and germ-free larvae have a higher glucose content than conventional-reared larvae. Both nutritional and immunological analyses indicate that gut bacteria are a burden in the beetle's larval development. These findings elucidate the impacts of gut microbiota on P. versicolora, and provide insight into tissue-specific responses to gut microflora in this pest at the genetic level, boosting our understanding of the molecular mechanisms underlying host-microbe interactions in leaf beetles and beyond.
昆虫肠道微生物对宿主的生理特征有深远影响，这些影响可以在局部（肠道）和全身（身体）水平上影响其生理机能。然而，宿主-微生物群相互作用的分子机制，尤其是在非模式昆虫中，仍然难以捉摸。最近，组织特异性转录组分析已被强调为研究宿主-微生物相互作用的有力工具。黄杨绢野螟是一种世界性的食叶害虫，主要以柳树和杨树为食。肠道微生物群与这种宿主甲虫之间的相互作用尚未得到研究。在此，我们研究了肠道微生物群对黄杨绢野螟幼虫体重的影响，比较了有无肠道微生物群时幼虫的营养状况，并对其整个发育幼虫阶段的肠道细菌负荷进行了分析。然后，我们对无菌和非无菌幼虫的肠道和体组织进行了比较转录组分析。最后，我们验证了营养代谢和免疫相关代表性基因的表达模式。结果表明，常规饲养的幼虫体重增长缓慢，总细菌负荷在第 5 天发育日增加，无菌幼虫的葡萄糖含量高于常规饲养的幼虫。营养和免疫分析均表明，肠道细菌是幼虫发育的负担。这些发现阐明了肠道微生物群对黄杨绢野螟的影响，并深入了解了该害虫在遗传水平上肠道微生物群对组织特异性的反应，从而增进了我们对食叶甲虫及其它昆虫宿主-微生物相互作用分子机制的理解。
