Systemin/Jasmonate-Mediated Systemic Defense Signaling in Tomato Sun Jia-Qiang , Jiang Hong-Ling , Li Chuan-You   Molecular Plant  Volume 4, Issue 4, Pages 607-615 (July 2011) DOI: 10.1093/mp/ssr008 Copyright © 2011 The Authors. All rights reserved. Terms and Conditions

Figure 1 A Proposed Model for Systemin/Jasmonate-Signaled Defense Response in Tomato. Insect attack or wounding triggers the cleavage of systemin from its precursor protein prosystemin. Interaction of systemin with its proposed receptor (R) in the plasma membrane (PM) activates the octadecanoid pathway for JA biosynthesis with a so-far unknown mechanism. In the choloroplast, the sequential activities of several enzymes involved in the initial steps of JA biosynthesis including lipoxygenase (LOX), allene oxide synthase (AOS), and allene oxide cyclase (AOC) led to the production of 12-oxo-phytodienoic acid (12-OPDA). 12-OPDA is then transported to the peroxisome and reduced to 3-oxo-2(29[Z]-pentenyl)-cyclopentane-1-octanoic acid (OPC:8). OPC:8 undergoes three rounds of β-oxidation to yield JA. Perception of JA by the SCFCOI1 receptor complex leads to degradation of the JAZ family repressors and, as a result, relieves the transcription factors (TFs) activity for JA-induced defense gene expression. Several tomato mutants known to be able to block systemin/jasmonate-induced defense gene expression are indicated. Molecular Plant 2011 4, 607-615DOI: (10.1093/mp/ssr008) Copyright © 2011 The Authors. All rights reserved. Terms and Conditions

Figure 2 Phylogenetic Analyses of the JAZ Family Genes in Arabidopsis and their Respective Homologs in Tomato. Phylogenetic tree based on AtJAZ1 in Arabidopsis (red) and their respective homologs in tomato (blue) are presented. Branch lengths are proportional to the estimated evolutionary distance. Molecular Plant 2011 4, 607-615DOI: (10.1093/mp/ssr008) Copyright © 2011 The Authors. All rights reserved. Terms and Conditions