Heterodera avenae Effector HaGLAND5 Promotes Nematode Parasitism by Suppressing Wheat Immunity through Enhancing Acetylation of Susceptibility Gene TaEMB3003

Abstract

Wheat, a cornerstone of global food security, is critically threatened by pests such as the cyst nematodeHeterodera avenae, which secretes effector HaGLAND5 to manipulate wheat susceptibility. Here, we demonstrate that HaGLAND5 directly interacts with the pyruvate dehydrogenase subunit TaEMB3003 in wheat. TaEMB3003 functions as a susceptibility factor, where its overexpression increases nematode infection by 147.06%, whereas silencing reduces infestation by 53.96%. Mechanistically, TaEMB3003 suppresses PTI (inhibiting NbPti5, NbAcre31, and NbGras2 expression), attenuates a flg22-induced ROS burst, and disrupts SA/JA signaling (downregulating TaFAD, TaLOX, TaPAL, and TaPR1). Critically, HaGLAND5 enhances TaEMB3003 acetylation at lysine 39 (K39) and K39A mutation abolishes TaEMB3003-mediated susceptibility. Our findings reveal a novel strategy whereby a nematode effector hijacks a host metabolic enzyme via post-translational modification to suppress immunity and promote parasitism.