APT1 and NACsa Are Required for GlyI Expression and GSH/GSSG Ratio Regulation.
(A) Transcript levels of MtGlyI in 2-week-old wild-type (R108) plants or the apt1 mutant subjected to 50% PEG-8000 treatment for 0, 0.5, 1, 2, and 4 h. The error bars represent the se of two samples. The asterisk indicates a significant difference between apt1 mutants and wild-type plants under PEG-imposed dehydration stress (Kruskal-Wallis nonparametric test, **P < 0.01).
(B) The apt1 mutant and wild-type plant tissues (0.1 g) were used to measure the total glutathione (GSH+GSSG) and GSSG, and the GSH/GSSG ratio was calculated under 50% PEG-8000 treatment for 0, 0.5, 1, 2, and 4 h. The error bars represent se of two samples. The asterisk indicates a significant difference between apt1 mutants and wild-type plants under PEG-imposed dehydration stress (Kruskal-Wallis nonparametric test, **P < 0.01).
(C) Transcript levels of MtGlyI in 2-week-old of wild-type (R108) plants or nacsa-1 mutant with treated with 50% PEG-8000 for 0, 0.5, 1, 2, and 4 h. The error bars represent the se of two samples. The asterisk indicates a significant difference between nacsa mutants and wild-type plants under PEG-imposed dehydration stress (Kruskal-Wallis nonparametric test, **P < 0.01).
(D) The GSH/GSSG ratio of ectopic expression of MfNACsa, nacsa-1 mutant, and wild-type R108 plants under PEG-imposed dehydration stress. Total glutathione (GSH+GSSG) and GSSG were measured in leaf tissues of tested plants (0.1 g) subjected to 50% PEG-8000 treatment for 0, 0.5, 1, 2, and 4 h. The error bars represent the se of two samples. The asterisk indicates a significant difference between lines ectopically expressing MfNACsa or nacsa-1 mutant compared with wild-type plants under PEG-imposed dehydration stress (Kruskal-Wallis nonparametric test, **P < 0.01).