The Arabidopsis downy mildew resistance gene, RPP13-Nd, functions independently of NDR1 and EDS1 and does not require the accumulation of salicylic acid.
RPP13-Nd-mediated resistance prevents parasitism by five isolates of Peronospora parasitica (At) in a transgenic Arabidopsis. Columbia background. We tested the effect of a number of known disease resistance mutations on the RPP13-Nd function and found that resistance remained unaltered in plants carrying mutations in either EDS1 or NDR1 and in double ndr1-1/eds1-2 mutant lines. Furthermore, we found that pbs2, pad4-1, npr1-1, and rps5-1, which compromise resistance to a number of P. parasitica (At) isolates, had no affect on RPP13-Nd function. In addition, RPP13-Nd-mediated resistance remained unchanged in a background of salicylic acid depletion (nahG). We conclude that RPP13-Nd is the first Arabidopsis R gene product reported to act via a novel signaling pathway that is independent of salicylic acid-mediated responses and is completely independent of NDR1 and EDS1.
Bittner-Eddy
P D
PD
Horticulture Research International, Wellesbourne, Warwick, UK.
Beynon
J L
JL
D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism / Q000382:microbiology; D029681:Arabidopsis Proteins; D002265:Carboxylic Ester Hydrolases / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D006899:Mixed Function Oxygenases / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D009868:Oomycetes / Q000472:pathogenicity*; D010641:Phenotype; D010935:Plant Diseases / Q000235:genetics*; D018515:Plant Leaves / Q000378:metabolism / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D020156:Salicylic Acid / Q000378:metabolism*; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
D029681:Arabidopsis Proteins; D004268:DNA-Binding Proteins; C118837:EDS1 protein, Arabidopsis; C109369:NDR1 protein, Arabidopsis; D010940:Plant Proteins; C408688:RPP13 protein, Arabidopsis; D014157:Transcription Factors; D006899:Mixed Function Oxygenases; C022619:salicylate 1-monooxygenase; D002265:Carboxylic Ester Hydrolases; C400766:PAD4 protein, Arabidopsis; D020156:Salicylic Acid