A key role for the Arabidopsis WIN3 protein in disease resistance triggered by Pseudomonas syringae that secrete AvrRpt2

Mol Plant Microbe Interact. 2007 Oct;20(10):1192-200. doi: 10.1094/MPMI-20-10-1192.


Effector proteins injected by the pathogenic bacteria Pseudomonas syringae into plants can have profound effects on the pathogen-host interaction due to their efficient recognition by plants and the subsequent triggering of defenses. The AvrRpt2 effector triggers strong local and systemic defense (called systemic acquired resistance [SAR]) responses in Arabidopsis thaliana plants that harbor a functional RPS2 gene that encodes an R protein in the coiled-coil, nucleotide-binding domain, leucine-rich repeat class. The newly identified win3-T mutant shows greatly reduced resistance to P syringae carrying avrRpt2. In win3-T plants, RIN4 cleavage, an early AvrRpt2-induced event, is normal. However, salicylic acid accumulation is compromised, as is SAR induction and the local hypersensitive cell death response after infection by P syringae carrying avrRpt2. WIN3 encodes a member of the firefly luciferase protein superfamily. Expression of WIN3 at an infection site partially requires PAD4, a protein known to play a quantitative role in RPS2-mediated signaling. WIN3 expression in tissue distal to an infection site requires multiple salicylic acid regulatory genes. Finally, win3-T plants show modestly increased susceptibility to virulent P syringae and modestly reduced SAR in response to P. syringae carrying avrRpm1. Thus, WIN3 is a key element of the RPS2 defense response pathway and a basal and systemic defense component.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Arabidopsis / genetics
  • Arabidopsis / metabolism
  • Arabidopsis / microbiology*
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism
  • Arabidopsis Proteins / pharmacology
  • Arabidopsis Proteins / physiology*
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism
  • Immunity, Innate
  • Intracellular Signaling Peptides and Proteins
  • Luciferases, Firefly / genetics
  • Luciferases, Firefly / pharmacology*
  • Models, Biological
  • Plant Diseases
  • Pseudomonas syringae / pathogenicity*
  • Virulence / genetics


  • Arabidopsis Proteins
  • AvrRpm1 protein, Pseudomonas syringae
  • Bacterial Proteins
  • Carrier Proteins
  • Intracellular Signaling Peptides and Proteins
  • RIN4 protein, Arabidopsis
  • RPS2 protein, Arabidopsis
  • avrRpt2 protein, Pseudomonas syringae
  • Luciferases, Firefly
  • WIN3 protein, Arabidopsis