A Novel CFEM Effector in Fusarium verticillioides Required for Virulence Involved in Plant Immunity Suppression and Fungal Cell Wall Integrity

Common in Fungal Extracellular Membrane (CFEM) effectors, a unique class of fungal-specific proteins, play critical roles in host-pathogen interactions. While CFEM proteins have been extensively characterized in phytopathogens, their presence and functions in <i>Fusarium verticillioides</i> remained unexplored. Here, we systematically identified 19 CFEM-containing proteins in <i>F. verticillioides</i>, among which FvCFEM12 exhibited secretory activity and plant infection-induced expression. Functional characterization revealed that FvCFEM12 suppressed Bax- and INF1-triggered cell death in <i>Nicotiana benthamiana</i> leaves. Furthermore, heterologous expression of FvCFEM12 in maize leaves using <i>P. syringae</i> strain D36E can compromise immune responses against bacterial pathogens. Deletion of FvCFEM12 impaired fungal virulence, altered hyphal morphology, and reduced cell wall stress tolerance. Interestingly, FvCFEM12 physically interacted with the maize wall-associated receptor kinase ZmWAK17ET, and targeted silencing of ZmWAK17 in maize enhanced susceptibility to <i>F. verticillioides</i>. Our findings revealed that FvCFEM12 is a dual-function effector that suppresses plant immunity and maintains fungal cell wall integrity, thereby orchestrating fungal pathogenicity at the host-pathogen interface.