Figure 7.
CycC1;1 interferes WRKY75-mediated transcriptional activation for SOS1. A) LUC reporter gene assay showing the effect of CycC1;1 on WRKY75-mediated activation of SOS1 expression. The relative LUC intensity represents the SOS1pro:LUC activity relative to the internal control (REN driven by the 35S promoter). The activity of SOS1pro:LUC without WRKY75 expression was set to 1. Data are means ± Sd (n = 3). B) The expression of SOS1 in 5-d-old wild-type, cycc1;1, wrky75-25, and cycc1;1 wrky75-25 mutant seedlings treated with 0 mM or 100 mM NaCl for 6 h. Data are means ± Sd (n = 3). Bars with different letters indicate significant differences at P < 0.05, determined using ANOVA with a Tukey's multiple comparison test. C) The expression of WRKY75 in 5-d-old wild-type and cycc1;1 mutant seedlings treated without or with 100 mM NaCl for 12 h. Data are means ± Sd (n = 3). ns, no significant differences. D to F) Phenotypes D) of the wild-type, cycc1;1, wrky75-25, and cycc1;1 wrky75-25 mutant plants grown on 1/2× MS medium supplemented with 0 mM, 125 mM, 135 mM, or 150 mM NaCl for 5 d. Quantitative analysis of seed germination E) and cotyledon greening rates F) of plants grown on 1/2× MS medium supplemented with 0 mM or 125 mM NaCl for 7 d. Data are means ± Sd (n = 3). G to I) Root elongation and fresh weight analysis. Five-day-old wild-type, cycc1;1, wrky75-25, and cycc1;1 wrky75-25 mutant plants were transferred to 1/2× MS medium supplemented with 0 mM or 125 mM NaCl for additional growth. The photographs were taken 5 d after transfer G). Bar = 1 cm. The lengths of newly grown roots H) and the fresh weights I) of the seedlings were also analyzed. Data are means ± Sd (n = 15 for root length and n = 3 for fresh weight). Bars with different letters indicate significant differences at P < 0.05, determined using ANOVA with a Tukey's multiple comparison test.