Dynamic cross-talk between host primary metabolism and viruses during infections in plants

• Plant viruses are important modulators of primary metabolism in infected cells.
• Viruses induce sink metabolism, photosynthesis repression and enhanced respiration.
• Metabolic alterations meet energy demands for viral multiplication and defense.
• Plant viruses provide metabolic acclimation against cellular stress.

Upon infection plant viruses modulate cellular functions and resources to survive and reproduce. Plant cells in which the virus is replicating are transformed into strong metabolic sinks. This conversion gives rise to a massive reprogramming of plant primary metabolism. Such a metabolic shift involves perturbations in carbohydrates, amino acids and lipids that eventually lead to increase respiration rates, and/or decrease in photosynthetic activity. By doing so, plants provide metabolic acclimation against cellular stress and meet the increased demand for energy needed to sustain virus multiplication and defense responses against viruses. This review will highlight our current knowledge pertaining to the contribution of primary metabolism to the outcome of viral infections in plants.