Negatively controls the salicylic acid (SA)-mediated pathway of programmed cell death in plant immunity. Constitutively activated HR-like cell death phenotype with endogenous accumulation of high levels of salicylic acid (SA) and constitutively activated defense phenotype. Dwarf plant with spotted necrotic lesions on its rosette and cauline leaves. Accumulation of high levels of callose and autofluorescent phenolic compounds localized to the necrotic lesions. Belongs to the complement C6/C7/C8/C9 (TC 1.C.39) family.