Polycalin is involved in the action mechanism of Cry2Aa toxin in Helicoverpa armigera(Hübner)  

作　　者：WANG Bing-jie WANG Ya-nan WEI Ji-zhen LIU Chen CHEN Lin Myint Myint Khaing LIANG Ge-mei 

机构地区：[1]State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences [2]Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences [3]Key Laboratory of Integrated Pest Management of Tropical Crops, Ministry of Agriculture

出　　处：《Journal of Integrative Agriculture》2019年第3期627-635,共9页农业科学学报（英文版）

基　　金：supported by the Key Project for Breeding Genetically Modified Organisms, China (2016ZX08011002);the National Natural Science Foundation of China (31621064);the Fundamental Research Funds for Central Non-profit Scientific Institution, China (Y2017JC34)

摘　　要：Receptor proteins on the brush border membrane of the insect midgut epithelium are involved in the mode of action of insecticidal Cry proteins from Bacillus thuringiensis(Bt). Polycalin has been identified as a binding protein of the Bt Cry1 Ac toxin in several Lepidoptera including Helicoverpa armigera, but its role in the action mechanism of Cry2 Aa is still unclear. In this study, we investigated the binding characteristics of polycalin from the midgut of H. armigera with Cry2 Aa and its role in the toxicity of Cry2 Aa. The results demonstrated that heterologously expressed H. armigera polycalin peptide could bind with Cry2 Aa with high affinity(K_d=32 nmol L^(–1)). The toxicity of Cry2 Aa decreased by 27% after H. armigera larvae ingested polycalin antisera. These results suggested that polycalin could be a potential functional receptor for Cry2 Aa, and it plays an important role in the susceptibility of H. armigera to Cry2 Aa.Receptor proteins on the brush border membrane of the insect midgut epithelium are involved in the mode of action of insecticidal Cry proteins from Bacillus thuringiensis(Bt). Polycalin has been identified as a binding protein of the Bt Cry1 Ac toxin in several Lepidoptera including Helicoverpa armigera, but its role in the action mechanism of Cry2 Aa is still unclear. In this study, we investigated the binding characteristics of polycalin from the midgut of H. armigera with Cry2 Aa and its role in the toxicity of Cry2 Aa. The results demonstrated that heterologously expressed H. armigera polycalin peptide could bind with Cry2 Aa with high affinity(K_d=32 nmol L^(–1)). The toxicity of Cry2 Aa decreased by 27% after H. armigera larvae ingested polycalin antisera. These results suggested that polycalin could be a potential functional receptor for Cry2 Aa, and it plays an important role in the susceptibility of H. armigera to Cry2 Aa.

关 键 词：HELICOVERPA ARMIGERA polycalin INSECTICIDAL toxicity ANTISERA binding AFFINITY 

分 类 号：S433[农业科学—农业昆虫与害虫防治]