Insect pathogenic fungus interacts with the gut microbiota to accelerate mosquito mortality
Insect pathogenic fungus interacts with the gut microbiota to accelerate mosquito mortality
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DOI：
10.1073/pnas.1703546114
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发表时间：
2017-06-06
影响因子：
11.1
通讯作者：
Wang, Sibao
中科院分区：
文献类型：
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作者：
Wei, Ge;Lai, Yiling;Wang, Sibao
昆虫肠道菌群在调节宿主与肠道病原体之间的相互作用中起着至关重要的作用。与病毒、细菌和寄生虫不同，它们需要被摄入才能引起疾病，昆虫病原真菌通过角质层感染昆虫并在血淋巴中增殖。然而，肠道微生物群和昆虫病原真菌之间的相互作用是未知的。在这里，我们表明致病真菌球孢白僵菌与肠道微生物群相互作用，加速蚊子死亡。在局部真菌感染后，具有肠道微生物群的蚊子比没有微生物群的蚊子死得更快。此外，真菌感染导致蚊子肠道微生物群的生态失调，肠道细菌负荷显著增加，细菌多样性显著降低。特别是，条件致病性细菌粘质沙雷氏菌在中肠中过度生长并移位到血腔，这促进了真菌对蚊子的杀灭。我们进一步揭示，真菌感染下调中肠抗菌肽和双氧化酶的表达。中肠中Duox下调是由B分泌毒素卵孢子蛋白介导的。巴西纳。我们的研究结果揭示了肠道微生物群在B中的重要贡献。杀球孢活性，为昆虫真菌致病机制提供了新的见解。
The insect gut microbiota plays crucial roles in modulating the interactions between the host and intestinal pathogens. Unlike viruses, bacteria, and parasites, which need to be ingested to cause disease, entomopathogenic fungi infect insects through the cuticle and proliferate in the hemolymph. However, interactions between the gut microbiota and entomopathogenic fungi are unknown. Here we show that the pathogenic fungus Beauveria bassiana interacts with the gut microbiota to accelerate mosquito death. After topical fungal infection, mosquitoes with gut microbiota die significantly faster than mosquitoes without microbiota. Furthermore, fungal infection causes dysbiosis of mosquito gut microbiota with a significant increase in gut bacterial load and a significant decrease in bacterial diversity. In particular, the opportunistic pathogenic bacterium Serratia marcescens overgrows in the midgut and translocates to the hemocoel, which promotes fungal killing of mosquitoes. We further reveal that fungal infection down-regulates antimicrobial peptide and dual oxidase expression in the midgut. Duox down-regulation in the midgut is mediated by secretion of the toxin oosporein from B. bassiana. Our findings reveal the important contribution of the gut microbiota in B. bassiana-killing activity, providing new insights into the mechanisms of fungal pathogenesis in insects.