Downregulation of polyphenol oxidase in potato tubers redirects phenylpropanoids metabolism enhancing chlorogenate content and late blight resistance

LLORENTE BRIARDO; LÓPEZ M.G.; CARRARI F. ; ASIS, RAMON; DI PAOLA NARANJO R.D.; FLAWIA M.M. ; ALONSO G.D.; BRAVO ALMONACID F.

SPRINGER

Lugar: Berlin; Año: 2014 vol. 34 p. 2049 - 2049

and plants synthesize phenolic compounds involved in plant defense against invading pathogens through the phenylpropanoids pathway. Although not considered as part of the phenylpropanoids pathway, plant polyphenol oxidases (PPOs) are enzymes that catalyze cresolase and catecholase reactions on several phenolic compounds. Here, transgenic potato (Solanum tuberosum) tubers with downregulated PPO genes (-PPO) were challenged with the oomycete pathogen Phytophthora infestans to investigate the interactions between PPO, phenylpropanoids metabolism and disease resistance. We found that pathogen invasiveness was reduced in -PPO lines, while microscopic evidences suggested that the mechanism underlying the defense response involved the participation of phenolic compounds. Detailed metabolite profiling analyses demonstrated that the concentration of metabolites related to the phenylpropanoids pathway and chlorogenate in particular were largely altered in PPO-downregulated tubers. S