Specific adjustments in grapevine leaf proteome discriminating resistant and susceptible grapevine genotypes to Plasmopara viticola.
Grapevine downy mildew is an important disease affecting crop production leading to severe yield losses. This study aims to identify the grapevine cultivar-specific adjustments of leaf proteome that allow the discrimination between resistance and susceptibility towards P. viticola (constitutive (0h) and in after inoculation (6, 12 and 24h). Leaf proteome analysis was performed using 2D difference gel electrophoresis followed by protein identification via mass spectrometry. In addition, we analysed ROS production, antioxidant capacity, lipid peroxidation and gene expression. Proteins related to photosynthesis and metabolism allowed the discrimination of resistant and susceptible grapevine cultivars prior to P. viticola inoculation. Following inoculation increase of hydrogen peroxide levels, cellular redox regulation, establishment of ROS signalling and plant cell death seem to be key points differentiating the resistant genotype. Lipid associated signalling events, particularly related to jasmonates appear also to play a major role in the establishment of resistance. The findings from this study contribute to a better understanding of genotype-specific differences that account for a successful establishment of a defence response to the downy mildew pathogen.


BIOLOGICAL SIGNIFICANCE
Here, we present for the first time grapevine cultivar-specific adjustments of leaf proteome that allow the discrimination between resistance and susceptibility towards P. viticola (constitutive (0h) and in after inoculation (6, 12 and 24h). We have highlighted that, following inoculation, the major factors differentiating the resistant from the susceptible grapevine cultivars are the establishment of effective ROS signalling together with lipid-associated signalling events, particularly related to jasmonates. It is believed that plants infected with biotrophic pathogens suppress JA-mediated responses, however recent evidences shown that jasmonic acid signalling pathway in grapevine resistance against Plasmopara viticola. Our results corroborate those evidences and highlight the importance of lipid- signalling for an effective resistance response against the downy mildew pathogen.
['Figueiredo|Andreia|A|', 'Martins|Joana|J|', 'Sebastiana|Mónica|M|', 'Guerreiro|Ana|A|', 'Silva|Anabela|A|', 'Matos|Ana Rita|AR|', 'Monteiro|Filipa|F|', 'Pais|Maria Salomé|MS|', 'Roepstorff|Peter|P|', 'Coelho|Ana Varela|AV|']
D003517:Cyclopentanes D060467:Disease Resistance D015180:Electrophoresis, Gel, Two-Dimensional D018506:Gene Expression Regulation, Plant D005838:Genotype D050356:Lipid Metabolism D010084:Oxidation-Reduction D054883:Oxylipins D044742:Peronospora D010935:Plant Diseases D018515:Plant Leaves D020543:Proteome D015398:Signal Transduction D027843:Vitis
Jasmonic acid Lipid signalling Protein modulation Redox balance Vitis vinifera