P-371 - Potato virus Y interferes with carbohydrate metabolism to promote disease development

Potato virus Y (PVY) affects staples such as potato and several other solanaceous plants and is considered top-five economically important plant viruses in the world. Nicotiana benthamiana leaves infected with PVY necrotic strain, PVY^NTN were used to investigate the change in leaf metabolome using gas chromatography coupled with mass spectroscopy. Untargeted metabolic approach showed that upon PVY infection, carbohydrate metabolism is differentially regulated and showed higher accumulation of glucose-6-phophate and fructose-6-phosphate. Further, to understand the molecular mechanism of how PVY manipulates plant metabolism, a yeast-two-hybrid (Y2H) cDNA library of N. benthamiana was screened to identify potential host proteins that interact with viral coat protein (CP). We found PVY-CP interact cytosolic Phosphoglucomutase (cPGM). cPGM is an enzyme that catalyzes the reversible conversion of glucose-6-phosphate to glucose-1-phosphate and is involved in controlling the partitioning of sugar-phosphate into respiratory pathway, cell wall synthesis, and sucrose synthesis pathways. This interaction between the CP and cPGM was further confirmed by Y2H assay. cPGM expression in N. benthamiana plants was silenced using a tobacco rattle virus-based silencing vector. The inactivation of this gene resulted in restricted disease development, and reduced virus accumulation suggesting that PVY requires the metabolite of cPGM-mediated pathways. Results suggest that PVY-CP interacts with the cPGM and modulates the carbohydrate metabolism to facilitate viral pathogenesis.