线粒体编码基因Nad5、Nad6和Atp6参与锈赤扁谷盗磷化氢抗性形成OA北大核心CSTPCD

[Background]Cryptolestes ferrugineus is one of the most economically important stored-grain pests,and its phosphine resistance is particularly prominent.Mitochondria are important organelles in living organisms,which are the core site for insects to undergo respiratory metabolic reactions.Mitochondrial protein-coding genes(PCGs)are involved in regulating physiological processes of insects,such as respiratory rate,energy metabolism,and cell signal transduction.[Objective]The objective of this study is to clarify the roles of mitochondrial PCGs in phosphine resistance of C.ferrugineus.[Method]The respiratory rates of different phosphine resistant populations of C.ferrugineus were measured by using a CO2 detector.The Taicang and Shanghai populations of C.ferrugineus with greatest differences in phosphine resistance levels and respiratory rates were selected to analyze the expression patterns of mitochondrial PCGs by using RT-qPCR technology,and the activities of mitochondrial complexes I and V were measured as well.The expression levels of three key mitochondrial PCGs including Nad5,Nad6 and Atp6,and the activities of mitochondrial complex I and V were determined after phosphine fumigation treatments in C.ferrugineus.RNA interference(RNAi)was used to silence Nad5,Nad6 and Atp6,and then the changes of respiratory rate and phosphine sensitivity of C.ferrugineus were analyzed.[Result]There was a negative correlation between the respiratory rate and phosphine resistance levels of C.ferrugineus,that is,the respiratory rates significantly decreased with the increase of phosphine resistance levels.The RT-qPCR results showed that the expression levels of mitochondrial PCGs in the highly phosphine resistant population(Taicang population,RR=1 906.8)of C.ferrugineus were significantly lower than those in the relatively sensitive population(Shanghai population,RR=1.4),and the enzyme activities of mitochondrial complexes I and V were consistent with the expression patterns of mitochondrial PCGs.The expression levels of three key mitochondrial PCGs,Nad5,Nad6 and Atp6,and the activities of mitochondrial complexes I and V were significantly inhibited after phosphine fumigation treatments in C.ferrugineus.The key mitochondrial PCGs,Nad5,Nad6 and Atp6 were silenced by injecting dsRNA,which resulted in a significant decrease in respiratory rate and phosphine sensitivity of C.ferrugineus.[Conclusion]The mitochondrial PCGs are involved in phosphine resistance of C.ferrugineus.