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bioRxiv · 10.1101/537597

Conservation of N-hydroxy-pipecolic acid-mediated systemic acquired resistance in crop plants

Abstract

Signal propagation and the coordination of whole-organism responses in plants rely heavily on small molecules. Systemic acquired resistance (SAR) is one such process in which long-distance signaling activates immune responses in uninfected tissue as a way to limit the spread of a primary, localized infection. Recently, N-hydroxy pipecolic acid (NHP) was discovered and shown to coordinate SAR in Arabidopsis. Here, we provide metabolic and biochemical evidence that NHP is conserved across the plant kingdom and demonstrate a role for NHP in mediating SAR responses in tomato and pepper. We reconstituted the NHP biosynthetic pathway in planta and show that transient expression of two NHP biosynthetic genes in tomato induces enhanced resistance to a bacterial pathogen in distal tissue. Our results suggest engineering strategies to induce NHP-mediated SAR are a promising route to improve broad-spectrum pathogen resistance in crops. IN BRIEFEngineering NHP production is a promising strategy to enhance disease resistance in crops. HIGHLIGHTSO_LIArabidopsis N-hydroxy-pipecolic acid (NHP) pathway is conserved across the plant kingdom C_LIO_LIApplication of NHP to tomato and pepper plants induces a robust SAR response C_LIO_LIMetabolic engineering of the Arabidopsis NHP pathway in Solanum lycopersicum leads to enhanced NHP production and defense priming C_LIO_LIGenetic engineering for enhanced NHP production is a promising strategy to protect crop plants from multiple pathogens C_LI

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BibTeXRIS

Holmes, E., Chen, Y. C., Sattely, E., Mudgett, M. B.. 2019-02-01. Conservation of N-hydroxy-pipecolic acid-mediated systemic acquired resistance in crop plants. https://doi.org/10.1101/537597

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