Wolbachia are Gram-negative endosymbionts that are known to cause embry-onic lethality when infected male insects mate with uninfected females or with females carrying a different strain of Wolbachia,a situation chara...Wolbachia are Gram-negative endosymbionts that are known to cause embry-onic lethality when infected male insects mate with uninfected females or with females carrying a different strain of Wolbachia,a situation characterized as cytoplasmice incom-patibility(CD).However,the mechanism of CI is not yet fully understood,although re-cent studies on Drosophila melanogaster have achieved great progress.Here,we found that Wolbachia infection caused changes in the expressions of several immunity-related genes,including significant upregulation of kenny(key),in the testes of D.melanogaster.Overexpression of key in fly testes led to a significant decrease in egg hatch rates when these fies mate with wild-type females.Wolbachia-infected females could rescue this embryonic lethality.Furthermore,in key overexpressing testes terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling signal was significantly stronger than in the control testes,and the level of reactive oxygen species was significantly increased.Overexpression of key also resulted in alterations of some other immunity-related gene expressions,including the downregulation of Zn72D.Knockdown of Zn72D in fly testes also led to a significant decrease in egg hatch rates.These results suggest that Wolbachia might induce the defect in male host fertility by immunity-related pathways and thus cause an oxidative damage and cell death in male testes.展开更多
基金Authors thank Professor Scott O'Neill(Monash Univer-sity,Australia)for prov iding Dmel wMel flies.This work was supported by the National Natural Science Founda-tion of China(No.31672352).
文摘Wolbachia are Gram-negative endosymbionts that are known to cause embry-onic lethality when infected male insects mate with uninfected females or with females carrying a different strain of Wolbachia,a situation characterized as cytoplasmice incom-patibility(CD).However,the mechanism of CI is not yet fully understood,although re-cent studies on Drosophila melanogaster have achieved great progress.Here,we found that Wolbachia infection caused changes in the expressions of several immunity-related genes,including significant upregulation of kenny(key),in the testes of D.melanogaster.Overexpression of key in fly testes led to a significant decrease in egg hatch rates when these fies mate with wild-type females.Wolbachia-infected females could rescue this embryonic lethality.Furthermore,in key overexpressing testes terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling signal was significantly stronger than in the control testes,and the level of reactive oxygen species was significantly increased.Overexpression of key also resulted in alterations of some other immunity-related gene expressions,including the downregulation of Zn72D.Knockdown of Zn72D in fly testes also led to a significant decrease in egg hatch rates.These results suggest that Wolbachia might induce the defect in male host fertility by immunity-related pathways and thus cause an oxidative damage and cell death in male testes.