State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Key Laboratory of Traceability for Agricultural Genetically Modified Organisms, Ministry of Agriculture and Rural Affairs, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
State Key Laboratory of Rice Biology and Breeding & Ministry of Agricultural and Rural Affairs Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China.
Int J Mol Sci. 2023 Sep 14;24(18):14088. doi: 10.3390/ijms241814088.
Insects employ multifaceted strategies to combat invading fungi, with immunity being a promising mechanism. Immune pathways function in signal transduction and amplification, ultimately leading to the activation of antimicrobial peptides (AMPs). Although several studies have shown that immune pathways are responsible for defending against fungi, the roles of parasitoid immune pathways involved in antifungal responses remain unknown. In this study, we evaluated the roles of the Toll and IMD pathways of a pupal parasitoid, (Hymenoptera: Pteromalidae), in fighting against (Hypocreales: Cordycipitaceae). Successful colonization of on adults was confirmed by scanning electron microscopy (SEM). AMPs were induced upon infection. The knockdown of key genes, and , in Toll and IMD signaling pathways, respectively, significantly compromised insect defense against fungal infection. The knockdown of either or in dramatically promoted the proliferation of , resulting in a decreased survival rate and downregulated expression levels of AMPs against compared to controls. These data indicated that PpTollA and PpIMD participate in Toll and IMD-mediated activation of antifungal responses, respectively. In summary, this study has greatly broadened our knowledge of the parasitoid antifungal immunity against fungi.
昆虫采用多种策略来对抗入侵的真菌，而免疫是一种很有前途的机制。免疫途径在信号转导和放大中发挥作用，最终导致抗菌肽（AMPs）的激活。尽管有几项研究表明免疫途径负责抵御真菌，但寄生蜂免疫途径在抗真菌反应中的作用仍不清楚。在这项研究中，我们评估了一种蛹寄生蜂， （膜翅目：金小蜂科），在对抗 （Hypocreales：虫草科）时，Toll 和 IMD 途径的作用。扫描电子显微镜（SEM）证实了 成功定殖在 成虫上。感染后诱导 AMPs。分别敲低 Toll 和 IMD 信号通路中的关键基因 和 ，显著削弱了昆虫对真菌感染的防御能力。与对照相比，敲低 或 中的任何一个 都显著促进了 的增殖，导致存活率降低，对 的 AMPs 表达水平下调。这些数据表明，PpTollA 和 PpIMD 分别参与 Toll 和 IMD 介导的抗真菌反应的激活。总之，这项研究极大地拓宽了我们对寄生蜂对抗真菌的免疫机制的认识。
