Phytophthora infestans RxLR Effector PiAvr3b Targets NADP-Malic Enzyme to Promote Infection.

ABSTRACT: Phytophthora infestans, the causal agent of potato late blight, employs divergent RxLR effectors to undermine host immunity. One such effector, PiAvr3b, is known to activate resistance in plants carrying the R3b gene; however, its virulence mechanism in susceptible hosts remains unclear. Here, we demonstrate that PiAvr3b is delivered from haustoria through a brefeldin A (BFA)-insensitive pathway, bypassing the traditional endoplasmic reticulum-Golgi trafficking process. Through yeast two-hybrid screening and functional validation, we identified potato NADP-malic enzyme 3 (StME3) and its Nicotiana benthamiana ortholog NbME3 as the direct host target of PiAvr3b. StME3/NbME3 acts as a susceptibility factor; its overexpression enhanced pathogen colonisation, while silencing it confered resista

SUBMITTER: Gao W 

PROVIDER: S-EPMC12663868 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature