An ancient antimicrobial protein co-opted by a fungal plant pathogen for in planta mycobiome manipulation

Significance Microbes secrete a diversity of molecules into their environment to mediate niche colonization. During host ingress, plant pathogenic microbes secrete effector proteins that facilitate disease development, many of which deregulate host immune responses. We recently demonstrated that plant pathogens additionally exploit effectors with antibacterial activities to manipulate beneficial plant microbiota to promote host colonization. Here, we show that the fungal pathogenVerticillium dahliae has co-opted an ancient antimicrobial protein, which likely served in microbial competition in terrestrial environments before land plants existed, as effector for the manipulation of fungal competitors during host colonization. Thus, we demonstrate that pathogen effector repertoires comprise antifungal proteins and speculate that such effectors could be exploited for the development of antimycotics.