Transcriptomic and symptomatic features of PAMP triggered immunity in grapevine leaves

Abstract: Pathogen associated molecular pattern- (PAMP-) triggered immunity (PTI, basal immunity, basal resistance) is the first, line of plant defence against invading microorganisms. Pre-treatment of intact grape leaves with PTI elicitors lead to prevention of hypersensitive cell death caused by the incompatible pathogen Pseudomonas syringae pv. tomato DC3000 as well as cell death caused by Agrobacterium vitis and A. tumefaciens, causative agents of crown gall disease. Transcriptomic analysis of intact grape leaves infiltrated with the PTI inducer flagellin (flg22), alive A. vitis and heat killed A. vitis showed more than 250 highly modulated, up or down regulated genes. Interestingly, most of the genes modulated by alive A. vitis were strongly down regulated in comparison to treatment with heat-killed bacterium. A broad range of modulated genes were members of signal transduction. Relevant genes with a possible crucial role in grapevine PAMP-triggered immunity are presented.