Enhanced disease susceptibility 1 and salicylic acid act redundantly to regulate resistance gene-mediated signaling.
Resistance (R) protein-associated pathways are well known to participate in defense against a variety of microbial pathogens. Salicylic acid (SA) and its associated proteinaceous signaling components, including enhanced disease susceptibility 1 (EDS1), non-race-specific disease resistance 1 (NDR1), phytoalexin deficient 4 (PAD4), senescence associated gene 101 (SAG101), and EDS5, have been identified as components of resistance derived from many R proteins. Here, we show that EDS1 and SA fulfill redundant functions in defense signaling mediated by R proteins, which were thought to function independent of EDS1 and/or SA. Simultaneous mutations in EDS1 and the SA-synthesizing enzyme SID2 compromised hypersensitive response and/or resistance mediated by R proteins that contain coiled coil domains at their N-terminal ends. Furthermore, the expression of R genes and the associated defense signaling induced in response to a reduction in the level of oleic acid were also suppressed by compromising SA biosynthesis in the eds1 mutant background. The functional redundancy with SA was specific to EDS1. Results presented here redefine our understanding of the roles of EDS1 and SA in plant defense.
Venugopal
Srivathsa C
SC
Department of Plant Pathology, University of Kentucky, Lexington, KY, USA.
Jeong
Rae-Dong
RD
Mandal
Mihir K
MK
Zhu
Shifeng
S
Chandra-Shekara
A C
AC
Xia
Ye
Y
Hersh
Matthew
M
Stromberg
Arnold J
AJ
Navarre
DuRoy
D
Kachroo
Aardra
A
Kachroo
Pradeep
P
D017360:Arabidopsis / Q000235:genetics / Q000276:immunology* / Q000378:metabolism / Q000821:virology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D019184:Carmovirus / Q000502:physiology; D004268:DNA-Binding Proteins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D007113:Immunity, Innate; D019751:Intramolecular Transferases / Q000235:genetics / Q000378:metabolism; D010935:Plant Diseases / Q000276:immunology* / Q000821:virology; D020156:Salicylic Acid / Q000276:immunology* / Q000378:metabolism*; D015398:Signal Transduction
D029681:Arabidopsis Proteins; D004268:DNA-Binding Proteins; C118837:EDS1 protein, Arabidopsis; D019751:Intramolecular Transferases; C058486:isochorismate synthase; D020156:Salicylic Acid