A functional EDS1 ortholog is differentially regulated in powdery mildew resistant and susceptible grapevines and complements an Arabidopsis eds1 mutant.
Vitis vinifera (grapevine) is the most economically important deciduous fruit crop, but cultivated grapevine varieties lack adequate innate immunity to a range of devastating diseases. To identify genetic resources for grapevine innate immunity and understand pathogen defense pathways in a woody perennial plant, we focus in this study on orthologs of the central Arabidopsis thaliana defense regulator ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1). The family of EDS1-like genes is expanded in grapevine, and members of this family were previously found to be constitutively upregulated in the resistant variety 'Norton' of the North American grapevine species Vitis aestivalis, while they were induced by Erysiphe necator, the causal agent of grapevine powdery mildew (PM), in the susceptible V. vinifera variety 'Cabernet Sauvignon'. Here, we determine the responsiveness of individual EDS1-like genes in grapevine to PM and salicylic acid, and find that EDS1-like paralogs are differentially regulated in 'Cabernet Sauvignon', while two are constitutively upregulated in 'Norton'. Sequencing of VvEDS1 and VaEDS1 cDNA and genomic clones revealed high conservation in the protein-encoding sequence and some divergence of the promoter sequence in the two grapevine varieties. Complementation of the Arabidopsis eds1-1 mutant showed that the EDS1-like gene with highest predicted amino acid sequence similarity to AtEDS1 from either grapevine varieties is a functional ortholog of AtEDS1. Together, our analyses show that differential susceptibility to PM is correlated with differences in EDS1 expression, not differences in EDS1 function, between resistant 'Norton' and susceptible 'Cabernet Sauvignon'.
Division of Plant Sciences, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65203-7310, USA.
Fei
F
Gao
Xiaomei
X
Shu
Mohammad Babar
MB
Ali
Susanne
S
Howard
Nan
N
Li
Patrick
P
Winterhagen
Wenping
W
Qiu
Walter
W
Gassmann
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001203:Ascomycota / Q000187:drug effects / Q000502:physiology*; D018076:DNA, Complementary / Q000235:genetics; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D005816:Genetic Complementation Test; D018745:Genome, Plant / Q000235:genetics; D007113:Immunity, Innate / Q000187:drug effects; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D010802:Phylogeny; D010935:Plant Diseases / Q000235:genetics / Q000276:immunology* / Q000382:microbiology; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020156:Salicylic Acid / Q000494:pharmacology; D017386:Sequence Homology, Amino Acid; D027843:Vitis / Q000187:drug effects / Q000235:genetics / Q000276:immunology / Q000382:microbiology*
D029681:Arabidopsis Proteins; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; C118837:EDS1 protein, Arabidopsis; D010940:Plant Proteins; D012333:RNA, Messenger; D020156:Salicylic Acid