(A) Ten-day-old wild-type seedlings were treated at 4°C for 30 min or not treated (0 min). The relative phosphorylation levels of MPK3, MPK4, and MPK6 before and after cold treatment were determined by a quantitative phosphoproteomics assay. Data are means ± SD (n=3). Asterisks indicate statistically significant differences (**P < 0.01, Student’s t-test).
(B) Ten-day-old wild-type seedlings were treated at 4°C for 0, 5, 15, 30, and 60 min. Total proteins were extracted and immunoblotting assays were performed using anti-pTEpY, anti-MPK3, anti-MPK6, anti-MPK4, and anti-Actin.
(C) Ten-day-old wild-type seedlings were treated at 18°C, 10°C, and 4°C for 0, 15, and 30 min. The immunoblotting assays were performed using anti-pTEpY and anti-Actin. See also Figure S2 and Table S1.