Cross-Talk Between a Nematode Effector-Targeted Metabolic Enzyme and a Lectin Receptor Kinase Regulates Wheat Immunity.

The cereal cyst nematode (Heterodera avenae) is an obligate plant parasite that severely threatens wheat production. Previous studies have shown that its secreted effector HaGLAND5, suppresses host immunity and promotes nematode parasitism by enhancing acetylation at lysine 39 of TaEMB3003, the E2 subunit of the wheat pyruvate dehydrogenase complex. However, how this molecular interaction precisely regulates the immune response remains unclear. In this study, we identified a wheat L-type lectin receptor kinase, TaLecRK-S.4, and demonstrated its interaction with TaEMB3003. Genetic analyses showed that overexpression of TaLecRK-S.4 enhanced wheat resistance to H. avenae, whereas knockdown of its expression increased susceptibility. Notably, HaGLAND5-triggered acetylation of TaEMB3003 induced a significant decrease in the protein accumulation of both TaEMB3003 and TaLecRK-S.4. Our findings suggest a potential reciprocal regulatory model driven by the TaEMB3003-TaLecRK-S.4 interaction, elucidating how nematode effector reprograms host signaling networks to transmit metabolic perturbation into sustained suppression of PTI. This work provides new insights into plant interactions with obligate parasitic nematodes.