Point mutations of Dicer2 conferred Fusarium asiaticum resistance to RNAi-related biopesticide  

作　　者：Kaixin Gu Ran Wei Yidan Sun Xiaoxin Duan Jing Gao Jianxin Wang Yiping Hou Mingguo Zhou Xiushi Song 

机构地区：[1]Key Laboratory of Pesticide,College of Plant Protection,Nanjing Agricultural University,Nanjing 210095,China

出　　处：《Journal of Integrative Agriculture》2025年第2期623-637,共15页农业科学学报(英文版)

基　　金：funded by the National Natural Science Foundation of China(32372585);the Natural Science Foundation of Jiangsu Province,China(BK20231471);the National Training Program of Innovation and Entrepreneurship for Undergraduates,China(202210307013Z)。

摘　　要：The use of RNA interference(RNAi)technology to control pests is explored by researchers globally.Even though RNA is a new class of pest control compound unlike conventional chemical pesticides,the evolution of pest resistance needs to be considered.Here,we first investigate RNAi-based biopesticide resistance of Fusarium asiaticum,which is responsible for devastating diseases of plants,for example,Fusarium head blight.Five resistant strains were isolated from 500 strains that treated with UV-mutagenesis.The mutation common to all of the five resistant mutants occurred in the gene encoding Dicer2(point mutations at codon 1005 and 1007),which were under strong purifying selection pressure.To confirm whether the mutations in Dicer2 confer resistance to RNAi,we exchanged the Dicer2 locus between the sensitive strain and the resistant strain by homologous double exchange.The transformed mutants,Dicer2^(R1005D)and Dicer2^(E1007H),exhibited resistance to dsRNA in vitro.Further study showed that mutations of R1005D and E1007H affected the intramolecular interactions of Dicer2,resulting in the dysfunction of RNase III domain of Dicer2.The amount of sRNAs produced by Dicer2^(R1005D)and Dicer2^(E1007H)was extremely reduced along with variation of sRNA length.Together,these findings revealed a new potential mechanism of RNAi resistance and provided insight into RNAi-related biopesticide deployment for fungal control.

关 键 词：RNA interference DSRNA Dicer2 point mutation RESISTANCE Fusarium asiaticum 

分 类 号：S482[农业科学—农药学]