College of Plant Science, Jilin University, Changchun 130062, PR China.
School of Agricultural Science, Zhengzhou University, Zhengzhou 450001, PR China.
Pestic Biochem Physiol. 2022 Jun;184:105076. doi: 10.1016/j.pestbp.2022.105076. Epub 2022 Mar 10.
Chemosensory proteins (CSPs) are a class of small transporter proteins expressed only in arthropods with various functions beyond chemoreception. Previous studies have been reported that CSPs are involved in the insecticide resistance. In this study, we found that AgoCSP1, AgoCSP4, and AgoCSP5 were constitutively overexpressed in an insecticide-resistant strain of Aphis gossypii and showed higher expression in broad body tissue (including fat bodies) than in the midgut but without tissue specificity. However, the function of these three upregulated AgoCSPs remains unknown. Here, we investigated the function of AgoCSPs in resistance to the diamide insecticide cyantraniliprole. Suppression of AgoCSP1, AgoCSP4 and AgoCSP5 transcription by RNAi significantly increased the sensitivity of resistant aphids to cyantraniliprole. Molecular docking and competitive binding assays indicated that these AgoCSPs bind moderate with cyantraniliprole. Transgenic Drosophila melanogaster expressing these AgoCSPs in the broad body or midgut showed higher tolerance to cyantraniliprole than control flies with the same genetic background; AgoCSP4 was more effective in broad body tissue, and AgoCSP1 and AgoCSP5 were more effective in the midgut, indicating that broad body and midgut tissues may be involved in the insecticide resistance mediated by the AgoCSPs examined. The present results strongly indicate that AgoCSPs participate in xenobiotic detoxification by sequestering and masking toxic insecticide molecules, providing insights into new factors involved in resistance development in A. gossypii.
化感蛋白（CSPs）是一类仅在节肢动物中表达的小转运蛋白，具有多种除化学感受以外的功能。先前的研究报道 CSPs 参与了昆虫的抗药性。在这项研究中，我们发现 AgoCSP1、AgoCSP4 和 AgoCSP5 在棉蚜的抗药性品系中持续过表达，并且在宽体组织（包括脂肪体）中的表达高于中肠，但没有组织特异性。然而，这三种上调的 AgoCSP 的功能仍不清楚。在这里，我们研究了这些 AgoCSPs 在抵抗二酰胺类杀虫剂虫螨腈中的功能。通过 RNAi 抑制 AgoCSP1、AgoCSP4 和 AgoCSP5 的转录显著增加了抗性蚜虫对虫螨腈的敏感性。分子对接和竞争结合实验表明，这些 AgoCSPs 与虫螨腈中等结合。在宽体或中肠中表达这些 AgoCSPs 的转基因黑腹果蝇对虫螨腈的耐受性高于具有相同遗传背景的对照果蝇；AgoCSP4 在宽体组织中更有效，AgoCSP1 和 AgoCSP5 在中肠中更有效，表明宽体和中肠组织可能参与了由所检查的 AgoCSPs 介导的抗药性。这些结果强烈表明，AgoCSPs 通过隔离和掩盖有毒杀虫剂分子参与了外来化合物的解毒，为研究棉蚜抗药性发展的新因素提供了思路。
