Figure 5.

COP1 is required for selective degradation of BBX22 in the dark. A and B, The expression of both BBX22 transcript (A) and BBX22 protein (B) is higher in dark-grown cop1-4 plants than in wild-type (Col) plants. C, Northern-blot analysis was used to confirm the comparable BBX22-GFP transgene expression in these lines. The ethidium bromide-stained image was used to show equal loading of the total RNA samples. D, BBX22-GFP protein accumulates to high levels in cop1 mutants. Endogenous α-tubulin was a loading control (TUB).