The plant cuticle regulates apoplastic transport of salicylic acid during systemic acquired resistance

Transport of salicylic acid is important for systemic immunity and is regulated by osmotic pressure and cuticle permeability. The plant cuticle is often considered a passive barrier from the environment. We show that the cuticle regulates active transport of the defense hormone salicylic acid (SA)....

Full description

Saved in:
Bibliographic Details
Published in:Science advances 2020-05, Vol.6 (19), p.eaaz0478-eaaz0478
Main Authors: Lim, Gah-Hyun, Liu, Huazhen, Yu, Keshun, Liu, Ruiying, Shine, M. B., Fernandez, Jessica, Burch-Smith, Tessa, Mobley, Justin K., McLetchie, Nicholas, Kachroo, Aardra, Kachroo, Pradeep
Format: Article
Language:English
Subjects:
Applied Ecology
Plant Sciences
SciAdv r-articles
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Transport of salicylic acid is important for systemic immunity and is regulated by osmotic pressure and cuticle permeability. The plant cuticle is often considered a passive barrier from the environment. We show that the cuticle regulates active transport of the defense hormone salicylic acid (SA). SA, an important regulator of systemic acquired resistance (SAR), is preferentially transported from pathogen-infected to uninfected parts via the apoplast. Apoplastic accumulation of SA, which precedes its accumulation in the cytosol, is driven by the pH gradient and deprotonation of SA. In cuticle-defective mutants, increased transpiration and reduced water potential preferentially routes SA to cuticle wax rather than to the apoplast. This results in defective long-distance transport of SA, which in turn impairs distal accumulation of the SAR-inducer pipecolic acid. High humidity reduces transpiration to restore systemic SA transport and, thereby, SAR in cuticle-defective mutants. Together, our results demonstrate that long-distance mobility of SA is essential for SAR and that partitioning of SA between the symplast and cuticle is regulated by transpiration.
ISSN:2375-2548
2375-2548
DOI:10.1126/sciadv.aaz0478