Down-regulation of HaABCC3, potentially mediated by a cis-regulatory mechanism, is involved in resistance to Cry1Ac in the cotton bollworm, Helicoverpa armigera  

作　　者：Chongyu Liao Dandan Zhang Ying Cheng Yongbo Yang Kaiyu Liu Kongming Wu Yutao Xiao 

机构地区：[1]Shenzhen Branch,Guangdong Laboratory for Lingnan Modern Agriculture,Genome Analysis Laboratory of the Ministry of Agriculture,Agricultural Genomics Institute at Shenzhen,Chinese Academy of Agricultural Sciences,Shenzhen,China [2]The State Key Laboratory for Biology of Plant Disease and Insect Pests,Institute of Plant Protection,Chinese Academy of Agricultural Sciences,Beijing,China [3]College of Life Sciences,Central China Normal University,Wuhan,China

出　　处：《Insect Science》2023年第1期135-145,共11页昆虫科学（英文版）

基　　金：supported by Shenzhen Natural Science Foundation(grant numberJCYJ20200109150629266);Shenzhen Science and Technology Program(grant number KQTD20180411143628272).

摘　　要：Evolution of resistance to Cry proteins in multiple pest insects has been threatening the sustainable use of Bacillus thuringiensis(Bt)-transgenic crops.Better understanding about the mechanism of resistance to Cry proteins in insects is needed.Our preliminary study reported that the transcription of HaABCC3 was significantly decreased in a near-isogenic line(LFC2)of a Cry1Ac-resistant strain(LF60)of the global pest Helicoverpa armigera.However,the causality between HaABCC3 downregulation and resistance to Cry1Ac remains to be verified,and the regulatory mechanism underlying the HaABCC3 downregulation is still unclear.In this study,our data showed that both HaABCC3 and HaABCC3 downregulation were genetically linked to resistance to Cry1Ac in LF60.However,no InDels were observed in the coding sequence of HaABCC3 from LF60.Furthermore,F_(1) offspring from the cross of LF60 and a HaABCC2/3-knockout mutant exhibited moderate resistance to Cry1Ac toxin;this indicated that the high resistance to CrylAc toxin in LF60 may have resulted from multiple genetic factors,including HaABCC2 missplicing and HaABCC3 downregulation.Results from luciferase reporter assays showed that promoter activity of HaABCC3 in LF60 was significantly lower than that in the susceptible strain,which indicated that HaABCC3 downregulation was likely mediated by promoter variation.Consistently,multiple variations of the GATA-or FoxA-binding sites in the promoter region of HaABCC3 were identified.Collectively,all results in this study suggested that the downregulation of HaABCC3 observed in the H.armigera LF60 strain,which is resistant to CrylAc,may be mediated by a cis-regulatory mechanism.

关 键 词：ATP-binding cassette transporter Bacillus thuringiensis CIS-REGULATION Cry toxin Helicoverpa armigera 

分 类 号：S43[农业科学—农业昆虫与害虫防治]