Abstract
To study the association of glutathione with disease resistance in plants, we investigated the effects of glutathione on PR-1 expression in the lsd (lesions simulating disease) mutants of Arabidopsis thaliana that spontaneously exhibit cell death. The total glutathione levels in the lsd mutants increased at day 2 to 4 after the transition to the lesion-forming phase, accompanied with PR-1 expression. Application of GSSG or GSH at 10-5 M to the lsd1 mutant and of GSSG at 10-5 M to the lsd4 mutant promoted an increase in the total glutathione levels and hastened the PR-1 accumulations in the post-transition. However, application of GSSG at 10-3 M did not accelerate PR-1 accumulation as much as that at 10-5 M, whereas it promoted an increase in the glutathione accumulation. These results suggest that PR-1 is expressed in the appropriate levels of glutathione in the cell during cell death.
