Waqas Muhammad Saad, Xu Xiao, Zhang Pengfei, Guo Jin, Hu Shaojing, You Yinwei, Zhang Long
Institute of Plant Protection, Shandong Key Laboratory for Green Prevention and Control of Agricultural Pests, Shandong Academy of Agricultural Sciences, Jinan, Shandong, China.
Hebei Provincial Jujube Kernel Utilization Technology Innovation Center, Department of Chemical Engineering and Biotechnology, Xingtai University, Xingtai, China.
Front Immunol. 2025 Apr 28;16:1565964. doi: 10.3389/fimmu.2025.1565964. eCollection 2025.
The innate immune system provides defense against invading pathogens in insects and mammals.
We conducted transcriptomic analyses of the locust under infection to clarify temporal variation in its molecular immune response.
We found that fat body cells and hemocytes play different roles in the immune response of locusts to infection at different time points after inoculation, and melanization was the main process underlying the immune response of female locusts. Most pattern recognition receptors (PRR) genes were up-regulated in fat body cells and down-regulated in hemocytes from 24 h to 72 h after inoculation. This means that fat body cells, but not hemocytes, would be able to precisely recognize invading pathogens. Most serine protease inhibitors (SERPINs) genes and clip domain serine proteinase (CLIP) genes were up-regulated in fat body cells. However, most were down-regulated in hemocytes, which indicated that serine proteinases may be inhibited to activate downstream reactions involving the prophenoloxidase (PPO), peroxidase (POD), and Toll pathways. Most lysozymes, PPOs, and peroxiredoxin (PRDX) are effectors that were up-regulated in fat body cells 24 h after inoculation but down-regulated 48 h and 72 h after inoculation. Similar patterns were observed for effectors in hemocytes, which indicates that locust immune genes expression was suppressed by 72 h after inoculation, and might result in the weak melanization of locusts in response to infection.
Our findings enhance our understanding of insect-fungi interactions, as well as have implications for the development of more effective microbial control strategies for the management of locust populations.
先天免疫系统为昆虫和哺乳动物抵御入侵病原体提供防御。
我们对感染后的蝗虫进行了转录组分析，以阐明其分子免疫反应的时间变化。
我们发现，脂肪体细胞和血细胞在接种后不同时间点对蝗虫感染的免疫反应中发挥不同作用，黑化是雌性蝗虫免疫反应的主要过程。接种后24小时至72小时，大多数模式识别受体（PRR）基因在脂肪体细胞中上调，而在血细胞中下调。这意味着脂肪体细胞而非血细胞能够精确识别入侵病原体。大多数丝氨酸蛋白酶抑制剂（SERPIN）基因和剪切域丝氨酸蛋白酶（CLIP）基因在脂肪体细胞中上调。然而，大多数在血细胞中下调，这表明丝氨酸蛋白酶可能被抑制以激活涉及前酚氧化酶（PPO）、过氧化物酶（POD）和Toll途径的下游反应。大多数溶菌酶、PPO和过氧化物还原酶（PRDX）是效应分子，在接种后24小时在脂肪体细胞中上调，但在接种后48小时和72小时下调。血细胞中的效应分子也观察到类似模式，这表明接种后72小时蝗虫免疫基因表达受到抑制，可能导致蝗虫对感染的黑化反应减弱。
我们的研究结果增进了我们对昆虫与真菌相互作用的理解，也对开发更有效的蝗虫种群微生物控制策略具有启示意义。
