Coronatine inhibits stomatal closure and delays hypersensitive response cell death induced by nonhost bacterial pathogens

Seonghee Lee; Yasuhiro Ishiga; Kristen Clermont; Kirankumar S Mysore

doi:10.7717/peerj.34

Coronatine inhibits stomatal closure and delays hypersensitive response cell death induced by nonhost bacterial pathogens

PeerJ. 2013 Feb 12:1:e34. doi: 10.7717/peerj.34. Print 2013.

Authors

Seonghee Lee¹, Yasuhiro Ishiga, Kristen Clermont, Kirankumar S Mysore

Affiliation

¹ The Samuel Roberts Noble Foundation , Plant Biology , Ardmore, Oklahoma , USA.

Abstract

Pseudomonas syringae is the most widespread bacterial pathogen in plants. Several strains of P. syringae produce a phytotoxin, coronatine (COR), which acts as a jasmonic acid mimic and inhibits plant defense responses and contributes to disease symptom development. In this study, we found that COR inhibits early defense responses during nonhost disease resistance. Stomatal closure induced by a nonhost pathogen, P. syringae pv. tabaci, was disrupted by COR in tomato epidermal peels. In addition, nonhost HR cell death triggered by P. syringae pv. tabaci on tomato was remarkably delayed when COR was supplemented along with P. syringae pv. tabaci inoculation. Using isochorismate synthase (ICS)-silenced tomato plants and transcript profiles of genes in SA- and JA-related defense pathways, we show that COR suppresses SA-mediated defense during nonhost resistance.

Keywords: Coronatine; Hypersensitive response; Nicotiana benthamiana; Nonhost resistance.

Grants and funding

This work was funded by the Samuel Roberts Noble Foundation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.