State Key Laboratory of Ecological Pest Control for Fujian/Taiwan Crops and College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China; Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou, China; Fujian Vocational College of Bioengineering, Fuzhou, China; Joint International Research Laboratory of Ecological Pest Control, Ministry of Education, Fuzhou, China; Key Laboratory of Integrated Pest Management for Fujian-Taiwan Crops, Ministry of Agriculture, Fuzhou, China.
State Key Laboratory of Ecological Pest Control for Fujian/Taiwan Crops and College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China; Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou, China; Key Laboratory of Integrated Pest Management for Fujian-Taiwan Crops, Ministry of Agriculture, Fuzhou, China; Institute of Insect Science and Technology, South China Normal University, Guangzhou, China.
Dev Comp Immunol. 2020 Jun;107:103661. doi: 10.1016/j.dci.2020.103661. Epub 2020 Feb 22.
The diamondback moth, Plutella xylostella, is the first insect to develop resistance to Bacillus thuringiensis (Bt) in the field. To date, little is known about the molecular mechanism of the interaction between Bt and midgut immunity in P. xylostella. Here, we report immune responses in the P. xylostella midgut to Bt strain Bt8010 using a combined approach of transcriptomics and quantitative proteomics. Many genes in the Toll, IMD, JNK and JAK-STAT pathways and antimicrobial peptide genes were activated at 18 h post-infection. In the prophenoloxidase (PPO) cascade, four serpin genes were activated, and the PPO1 gene was suppressed by Bt8010. Inhibition of the two PPO proteins was observed at 18 h post-infection. Feeding Bt8010-infected larvae recombinant PPOs enhanced their survival. These results revealed that the Toll, IMD, JNK and JAK-STAT pathways were triggered and participated in the immune defence of the midgut against Bt8010, while the PPO cascade was inhibited and played an important role in this process.
小菜蛾是田间首例对苏云金芽孢杆菌（Bt）产生抗性的昆虫。迄今为止，人们对 Bt 与小菜蛾中肠免疫相互作用的分子机制知之甚少。本研究采用转录组学和定量蛋白质组学相结合的方法，研究了 Bt 菌株 Bt8010 对小菜蛾中肠的免疫反应。在感染后 18 小时，Toll、IMD、JNK 和 JAK-STAT 途径以及抗菌肽基因中的许多基因被激活。在酚氧化酶（PPO）级联反应中，四个丝氨酸蛋白酶抑制剂基因被激活，而 PPO1 基因被 Bt8010 抑制。感染后 18 小时观察到两种 PPO 蛋白被抑制。喂食 Bt8010 感染幼虫重组 PPO 可提高其存活率。这些结果表明，Toll、IMD、JNK 和 JAK-STAT 途径被触发并参与了中肠对 Bt8010 的免疫防御，而 PPO 级联反应被抑制，并在这一过程中发挥了重要作用。
