The Botrytis cinereaeffector BcXYG1 suppresses immunity in Fragaria vescaby targeting FvBPL4 and FvACD11

Botrytis cinereais one of the most destructive pathogens in strawberry cultivation. Successful infection by B. cinerearequires releasing a large number of effectors that interfere with the plant’s immune system. One of the effectors required by B. cinereafor optimal virulence is the secreted protein BcXYG1, which is thought to associate with proteins near the plasma membrane of the host plant to induce necrosis. However, the host proteins that associate with BcXYG1 at the plasma membrane are currently unknown. We found that BcXYG1 binds to FvBPL4 and FvACD11 at the plasma membrane. Both FvBPL4 and FvACD11 are negative regulators of plant immunity in strawberry. Our results demonstrate that degradation of FvBPL4 by BcXYG1 promotes disease resistance while stabilization of FvACD11 by BcXYG1 suppresses the immune response. These findings suggest that BcXYG1 suppresses plant immunity and promotes B. cinereainfection by regulating FvBPL4 and FvACD11 protein levels.