Function
Essential regulator of plant defense, which plays a central role in resistance in case of infection by a pathogen. It is a common target for both type III avirulence proteins from P.syringae (AvrB, AvrRpm1 and AvrRpt2) and for the plant Resistance (R) proteins RPM1 and RPS2. In strains carrying the appropriate R gene for avirulence proteins of the pathogen, its association with avirulence proteins triggers a defense system including the hypersensitive response, which limits the spread of disease. In contrast, in plants lacking appropriate R genes, its association with avirulence proteins of the pathogen impairs the defense system and leads to the pathogen multiplication.