COP1 is required for the UV-B response leading to enhanced qE. (A) Immunoblot analysis of PSBS, LHCSR1, and LHCSR3 in WT (WT CC-124), cop1hit1, and cop1hit1/COP1 complemented strains (nos. 157 and 166) exposed for 6 h to UV-B. Tubulin levels are shown as loading control. (B) Quantitative RT-PCR analysis of PSBS, LHCSR1, and LHCSR3 RNA expression after 1 h of UV-B exposure in the WT, cop1hit1, and cop1hit1/COP1 complemented strain (no. 166). Data are normalized to levels in the WT in growth conditions (0). CNRQ, calibrated normalized relative quantities. (C) qE values after 6-h UV-B exposure in the WT, cop1hit1, and cop1hit1/COP1 complemented strains (nos. 157 and 166).