Differential disease resistance response in the @entity2247 XXXX mutant nec1.

@entity3785 @entity851 @entity2247 @entity10327 @entity39 @entity958 @entity72830 @entity377 @entity273 @entity3437
BACKGROUND: Although ion fluxes are considered to be an integral part of signal transduction during responses to pathogens, only a few ion channels are known to participate in the plant response to infection. @entity72830 is a disease resistance-related cyclic @entity377 -gated ion channel. @entity958 @entity72830 mutants @entity72830 and @entity72830 display an impaired hypersensitive response (HR), @entity851 , a constitutively active @entity3785 (SA)-mediated pathogenesis-related response and elevated resistance against bacterial pathogens. @entity2247 @entity72830 shares 67% aa identity with @entity72830 . The @entity2247 mutant nec1 comprising of a frame-shift mutation of @entity72830 displays a @entity39 phenotype and constitutively over-expresses PR-1, yet it is not known what effect the nec1 mutation has on @entity2247 resistance against different types of pathogens. RESULTS: nec1 mutant accumulated high amount of SA and @entity273 compared to parental cv. Parkland. Experiments investigating nec1 disease resistance demonstrated positive effect of nec1 mutation on non-host resistance against @entity3437 . tomato (Pst) at high inoculum density, whereas at normal Pst inoculum concentration nec1 resistance did not differ from wt. In contrast to augmented @entity3437 resistance, penetration resistance against biotrophic fungus Blumeria graminis @entity10327 . hordei (Bgh), the causal agent of powdery mildew, was not altered in nec1. The nec1 mutant significantly over-expressed race non-specific Bgh resistance-related genes BI-1 and MLO. Induction of BI-1 and MLO suggested putative involvement of nec1 in race non-specific Bgh resistance, therefore the effect of nec1on mlo-5-mediated Bgh resistance was assessed. The nec1/mlo-5 double mutant was as resistant to Bgh as Nec1/mlo-5 plants, suggesting that nec1 did not impair mlo-5 race non-specific Bgh resistance. CONCLUSIONS: Together, the results suggest that nec1 mutation alters activation of systemic acquired resistance-related physiological markers and non-host resistance in @entity2247 , while not changing rapid localized response during compatible interaction with host pathogen. Increased resistance of nec1 against non-host pathogen Pst suggests that nec1 mutation may affect certain aspects of @entity2247 disease resistance, while it remains to be determined, if the effect on disease resistance is a direct response to changes in SA signaling.
