Analysis of HKT1;1 expression in response to ABA and NaCl, and effects of hkt1 loss-of-function mutants on seed germination. A, RT-qPCR analysis for relative HKT1;1 transcript levels in pregerminated seedlings. Data represent means ± sd (three biological experiments, ∼30 seeds each). B, Seed germination assay of the indicated lines in the presence of 0 (control) or 200 mm NaCl. Germination rate was scored 5 d after plating. Data represent means ± se (three biological independent experiments, ∼100 seeds each), and letters above the bars represent statistically different values by Tukey’s honestly significant difference post hoc test (P < 0.01). C, GUS staining of Col-0 and camta6 mutant pregerminated transgenic seedlings harboring the HKT1;1pro:GUS or the HKT1;1[ABRE mutation]pro:GUS construct (wild type and mutated ABRE, respectively). Wild-type and mutated promoter sequences are depicted. The ABRE/mutation site is presented in larger, boldface letters. Bar = 1 mm. In A and C, seeds were treated with 0 (control) or 10 µm ABA or 200 mm NaCl for 16 h prior to seedling ejection.