« Previous Abstract"Representation of pheromones, interspecific signals, and plant odors in higher olfactory centers; mapping physiologically identified antennal-lobe projection neurons in the male heliothine moth"    Next AbstractProfile of volatile compounds in 11 brandies by headspace solid-phase microextraction followed by gas chromatography-mass spectrometry »

Plant J

Title:		Virulence systems of Pseudomonas syringae pv. tomato promote bacterial speck disease in tomato by targeting the jasmonate signaling pathway
Author(s):		Zhao Y; Thilmony R; Bender CL; Schaller A; He SY; Howe GA;
Address:		"Department of Energy-Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA"
Journal Title:		Plant J
Year:		2003
Volume:		36
Issue:		4
Page Number:		485 - 499
DOI:		10.1046/j.1365-313x.2003.01895.x
ISSN/ISBN:		0960-7412 (Print) 0960-7412 (Linking)
Abstract:		"Pseudomonas syringae pv. tomato strain DC3000 (Pst DC3000) causes bacterial speck disease on tomato. The pathogenicity of Pst DC3000 depends on both the type III secretion system that delivers virulence effector proteins into host cells and the phytotoxin coronatine (COR), which is thought to mimic the action of the plant hormone jasmonic acid (JA). We found that a JA-insensitive mutant (jai1) of tomato was unresponsive to COR and highly resistant to Pst DC3000, whereas host genotypes that are defective in JA biosynthesis were as susceptible to Pst DC3000 as wild-type (WT) plants. Treatment of WT plants with exogenous methyl-JA (MeJA) complemented the virulence defect of a bacterial mutant deficient in COR production, but not a mutant defective in the type III secretion system. Analysis of host gene expression using cDNA microarrays revealed that COR works through Jai1 to induce the massive expression of JA and wound response genes that have been implicated in defense against herbivores. Concomitant with the induction of JA and wound response genes, the type III secretion system and COR repressed the expression of pathogenesis-related (PR) genes in Pst DC3000-infected WT plants. Resistance of jai1 plants to Pst DC3000 was correlated with a high level of PR gene expression and reduced expression of JA/wound response genes. These results indicate that COR promotes bacterial virulence by activating the host's JA signaling pathway, and further suggest that the type III secretion system might also modify host defense by targeting the JA signaling pathway in susceptible tomato plants"
Keywords:		"Amino Acids/metabolism Cluster Analysis Cyclopentanes/*metabolism/pharmacology Gene Expression Regulation, Plant/drug effects Immunity, Innate/genetics Indenes/metabolism Solanum lycopersicum/*genetics/microbiology Mutation Oligonucleotide Array Sequence;"
Notes:		"MedlineZhao, Youfu Thilmony, Roger Bender, Carol L Schaller, Andreas He, Sheng Yang Howe, Gregg A eng GM57795/GM/NIGMS NIH HHS/ Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. England 2003/11/18 Plant J. 2003 Nov; 36(4):485-99. doi: 10.1046/j.1365-313x.2003.01895.x"