Characterization and functional analysis of β-1,3-galactosyltransferase involved in Cry1Ac resistance from Helicoverpa armigera(Hübner)  

作　　者：ZHANG Li-li LIANG Ge-mei GAO Xi-wu CAO Guang-chun GUO Yu-yuan 

机构地区：[1]College of Agriculture and Biotechnology, China Agricultural University [2]State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences

出　　处：《Journal of Integrative Agriculture》2015年第2期337-346,共10页农业科学学报（英文版）

基　　金：supported by the Key Technologies R&D Program of China during the 12th Five-Year Plan period (2012BAD19B05);the National Natural Science Foundation of China (30971921,31321004)

摘　　要：Carbohydrate chains are the principal antigens by which Bacillus thuringiensis（Bt） identify receptor proteins. The interaction between the antigen and Bt causes a pore in the membrane of midgut epithelial cells of insects. Receptor proteins, such as aminopeptidase N and alkaline phosphatase, are glycoproteins. Cadherin is another cell surface receptor protein which has potential glycosylation sites. Glycosyltransferase is very important for the synthesis and modification of receptor proteins. It can indirectly influence the function of Bt. The 1 950 bp full-length c DNA encoding β-1,3-galactosyltransferase was cloned from the the midgut of Helicoverpa armigera by degenerative PCR combined with RACE techniques（GAL-Harm, Gen Bank accession no.： GQ904195.1） with two potential N-glycosylation sites（^157NNTI^160 and ^272NKTL^275）. Protein sequence alignments revealed that H. armigera β-1,3-galactosyltransferase shared high identity with β-1,3-galactosyltransferase in other insect species. The expression level of the β-1,3-galactosyltransferase gene in Cry1Ac-resistant H. armigera larvae was 9.2-fold higher than that in susceptible strain. The function of β-1,3-galactosyltransferase was investigated using RNAi technique. The result showed Cry1 Ac enhanced the toxicity against the si RNA-treated larvae compared with non-si RNA-treated ones, which indicated β-1,3-galactosyltransferase played an important role for the insecticidal toxicity of Cry1 Ac in H. armigera.Carbohydrate chains are the principal antigens by which Bacillus thuringiensis（Bt） identify receptor proteins. The interaction between the antigen and Bt causes a pore in the membrane of midgut epithelial cells of insects. Receptor proteins, such as aminopeptidase N and alkaline phosphatase, are glycoproteins. Cadherin is another cell surface receptor protein which has potential glycosylation sites. Glycosyltransferase is very important for the synthesis and modification of receptor proteins. It can indirectly influence the function of Bt. The 1 950 bp full-length c DNA encoding β-1,3-galactosyltransferase was cloned from the the midgut of Helicoverpa armigera by degenerative PCR combined with RACE techniques（GAL-Harm, Gen Bank accession no.： GQ904195.1） with two potential N-glycosylation sites（^157NNTI^160 and ^272NKTL^275）. Protein sequence alignments revealed that H. armigera β-1,3-galactosyltransferase shared high identity with β-1,3-galactosyltransferase in other insect species. The expression level of the β-1,3-galactosyltransferase gene in Cry1Ac-resistant H. armigera larvae was 9.2-fold higher than that in susceptible strain. The function of β-1,3-galactosyltransferase was investigated using RNAi technique. The result showed Cry1 Ac enhanced the toxicity against the si RNA-treated larvae compared with non-si RNA-treated ones, which indicated β-1,3-galactosyltransferase played an important role for the insecticidal toxicity of Cry1 Ac in H. armigera.

关 键 词：β-1 3-galactosyltransferase CRY1AC resistance Helicoverpa armigera RNAI 

分 类 号：S435.622[农业科学—农业昆虫与害虫防治]