Chi Li#, Jun Qin, Yingqi Huang, Wenjing Shang, Jieyin Chen, Steven J. Klosterman, Krishna V. Subbarao, Xiaoping Hu*.Verticillium dahliae Effector VdCE11 Contributes to Virulence by Promoting Accumulation and Activity of the Aspartic Protease GhAP1 from Cotton. Microbiology Spectrum.2023. 11(1):e0354722.
Verticillium dahliae is a soilborne plant fungal pathogen that causes Verticillium wilt, a disease that reduces the yields of many economically important crops. Despite its worldwide distribution and harmful impacts, much remains unknown regarding how the numerous effectors of V. dahliae modulate plant immunity. Here, we identified the intracellular effector VdCE11 that induces cell death and defense responses in Nicotiana benthamiana to counter leaf pathogens such as Sclerotinia sclerotiorum and Botrytis cinerea . VdCE11 also contributes to the virulence of V. dahliae in cotton and Arabidopsis . Yeast two-hybrid library screening and immunoprecipitation revealed that VdCE11 interacts physically with the cotton aspartic protease GhAP1. GhAP1 and its Arabidopsis homolog AtAP1 are negative regulators of plant immunity, since disruption of either increased the resistance of cotton or Arabidopsis to V. dahliae . Further, VdCE11 plays a role in promoting the accumulation of the AP1 proteins and increasing its hydrolase activity. Taken together, these results indicate a novel mechanism regulating virulence whereby the secreted effector VdCE11 increases cotton susceptibility to V. dahliae by promoting the accumulation and activity of GhAP1.