Development of a transient expression system in grapevine via agro-infiltration

Area of Science:

• Plant molecular biology
• Plant pathology
• Agrobacterium-mediated transient expression

Background:

• Agrobacterium-mediated transient gene expression is crucial for plant gene function analysis.
• Grapevine (Vitis vinifera) disease resistance mechanisms are complex and require efficient research tools.
• Stilbenes are hypothesized to play a role in grapevine defense against pathogens like downy mildew.

Purpose of the Study:

• To develop and optimize a transient gene expression system in grapevine leaves using Agrobacterium.
• To investigate the role of stilbenes in grapevine defense against Plasmopara viticola through gene overexpression.
• To assess the impact of the agro-infiltration process itself on plant defense responses.

Main Methods:

• Optimization of Agrobacterium strain, plant material quality, and plant genotype for successful agro-infiltration.
• Utilized vacuum infiltration for transient expression of reporter genes (GUS and GFP) in grapevine leaves.
• Overexpressed stilbene synthase in grapevine leaves prior to Plasmopara viticola inoculation.

Main Results:

• Optimized protocols achieved consistent expression of GUS and GFP markers in grapevine leaves.
• Agro-infiltration itself triggered endogenous stilbene synthesis in grapevine leaves.
• The agro-infiltration procedure, independent of stilbene synthase overexpression, influenced Plasmopara viticola infection development.

Conclusions:

• The developed Agrobacterium-mediated transient expression system is a valuable tool for grapevine research.
• Agro-infiltration can induce plant defense responses, confounding direct gene function studies.
• Further investigation is needed to elucidate the specific factors responsible for the observed restriction of pathogen development.