An in-planta comparative study of Plasmopara viticola proteome reveals different infection strategies towards susceptible and Rpv3-mediated resistance hosts

Abstract

Plasmopara viticola, an obligate biotrophic oomycete, is the causal agent of one of the most harmful grapevine diseases, downy mildew. Within this pathosystem, much information is gathered on the host, as characterization of pathogenicity and infection strategy of a biotrophic pathogen is quite challenging. Molecular insights into P. viticola development and pathogenicity are just beginning to be uncovered, mainly by transcriptomic studies. Plasmopara viticola proteome and secretome were only predicted based on transcriptome data. In this study, we have identified the in-planta proteome of P. viticola during infection of a susceptible (‘Trincadeira’) and a Rpv3-mediated resistance (‘Regent’) grapevine cultivar. Four hundred and twenty P. viticola proteins were identified on a label-free mass spectrometry-based approach of the apoplastic fluid of grapevine leaves. Overall, our study suggests that, in the compatible interaction, P. viticola manipulates salicylic-acid pathway and isoprenoid biosynthesis to enhance plant colonization. Furthermore, during the incompatible interaction, development-associated proteins increased while oxidoreductases protect P. viticola from ROS-associated plant defence mechanism. Up to our knowledge this is the first in-planta proteome characterization of this biotrophic pathogen, thus this study will open new insights into our understanding of this pathogen colonization strategy of both susceptible and Rpv3-mediated resistance grapevine genotypes.

Proteins released into the plant apoplast by the obligate parasitic protist Albugo selectively repress phyllosphere‐associated bacteria

“…2b). Among these, 78 proteins (13.8%) carried a putative secretion signal, comparable to similar analysis in one other obligate biotrophic oomycete (Figueiredo et al ., 2022). Mitochondrial localization was assigned to 24 proteins (4.3%) with TP pred .…”

The pathogenicity of Plasmopara viticola: a review of evolutionary dynamics, infection strategies and effector molecules

“…Two PvRxLRs (PVIT_0014142.T1 and PVIT_0015177.T1) were identified in the proteome during the interaction with the tolerant cultivar ‘Regent,’ that present the Rpv 3.1 background. Four CRN proteins (PVIT_0001451.T1, PVIT_0006190.T1, PVIT_0006424.T1 and PVIT_0025443.T1) were identified for both interactions [ 77 , 78 ].…”

“…A B. cinerea mutant of this protein has shown defects in mycelial growth, sporulation, spore germination, and virulence [ 79 ]. It also attempts to manipulate the host’s metabolism and protect itself from the oxidative stress induced by the plant’s defense responses [ 77 , 78 ].…”