Inducible NAD overproduction in Arabidopsis alters metabolic pools and gene expression correlated with increased salicylate content and resistance to Pst‐AvrRpm1

• DOI: 10.1111/j.1365-313x.2012.04920.x
• Publication Date: 2012-01-23T12:45:28Z
• Authors: Pierre Pétriacq; Linda de Bont; Jutta Hager; Laure Didierlaurent; Caroline Mauve; Florence Guérard; Graham Noctor; Sandra Pelletier; Jean‐Pierre Renou; Guillaume Tcherkez; Bertrand Gakière
• Keywords: Quinolinate; Nicotinamide phosphoribosyltransferase

Summary Plant development and function are underpinned by redox reactions that depend on co‐factors such as nicotinamide adenine dinucleotide (NAD). NAD has recently been shown to be involved in several signalling pathways associated with stress tolerance or defence responses. However, the mechanisms which influences plant gene regulation, metabolism physiology still remain unclear. Here, we took advantage of Arabidopsis thaliana lines overexpressed nadC from E. coli , encodes biosynthesis enzyme quinolinate phosphoribosyltransferase (QPT). Upon incubation quinolinate, these accumulated were thus used inducible systems determine consequences an increased content leaves. Metabolic profiling showed clear changes metabolites aspartate‐derived amino acids NAD‐derived nicotinic acid. Large‐scale transcriptomic analyses indicated promoted induction various pathogen‐related genes salicylic acid (SA)‐responsive marker PR1. Extensive comparison databases further expression under high was similar obtained biotic stress, eliciting conditions SA treatment. inoculation avirulent strain Pseudomonas syringae pv. tomato Pst‐AvrRpm1 enhanced resistance bacteria infection exhibited ICS1 ‐dependent build‐up both conjugated free pools. We therefore concluded higher contents beneficial for immunity stimulating SA‐dependent pathogen resistance.