Figure 8.

MPK4 and COP1 Have Opposing Effects on Anthocyanin Accumulation.

(A) Anthocyanin contents of 12-d-old Arabidopsis seedlings of mpk4-3, 35S:MYB75^WT/mpk4-3, 35S:MYB75^DD/mpk4-3, and 35S:MYB75^AA/mpk4-3 transgenic seedlings grown on plates under low light and moderate high light (high light). FW, fresh weight. Error bars represent sd of three replicates (as described in Figure 2B).

(B) Quantitative real-time PCR analysis of DFR, LDOX, and UF3GT transcript levels in 12-d-old mpk4-3, 35S:MYB75^WT/mpk4-3, 35S:MYB75^DD/mpk4-3, and 35S:MYB75^AA/mpk4-3 transgenic seedlings grown on plates exposed to low light and moderate high light (high light) for 9 h, respectively. Results were normalized to ACTIN8, and expression levels of the genes in mpk4-3 under low light were set at one unit. Error bars indicate sd of three replicates (as described in Figure 2B).

(C) Twelve-day-old Arabidopsis seedlings of cop1-6, mpk4-3, and cop1-6 mpk4-3 grown on plates under low light and moderate high light (high light). Bars = 0.5 cm.

(D) Anthocyanin contents of the seedlings in (C). FW, fresh weight. Error bars represent sd of three replicates (as described in Figure 2B).

(E) Anthocyanin contents of 12-d-old Arabidopsis seedlings of the 35S:MYB75^WT, 35S:MYB75^DD, and 35S:MYB75^AA transgenic lines in the wild-type and cop1-6 backgrounds grown on plates under low light. FW, fresh weight. Error bars represent sd of three replicates (as described in Figure 2B).

(F) Quantitative real-time PCR analysis of MYB75 expression in wild-type, mpk4-3, and cop1-6 seedlings. Seedlings were placed in the dark or continuous low light for 4 d. Results were normalized to ACTIN8, and expression levels of the genes in wild type in the dark were set at one unit. Error bars indicate sd of three replicates (as described in Figure 2B).