The rb seedlings have an impaired GA signaling pathway, and mutation of DELLAs suppresses the Tor inhibition-caused greening phenotype. A, Analysis of GID1A/B/C gene expression by RT-qPCR in 5-d-old etiolated seedlings. The expression level of UBQ10 was used as an internal standard. Error bars represent sd (n = 3). B, Greening rates of 4-d-old etiolated seedlings followed by 2 d of white light with or without exogenous GA treatment. Data are means ± se (n = 3, more than 80 seedlings for each biological replicate). DMSO, Dimethyl sulfoxide. C, Western blot of DELLA proteins in 5-d-old etiolated seedlings. A protein gel stained with Coomassie Blue is shown as a loading control. D, Greening rates of etiolated seedlings grown in the dark for 5 d before exposure to light for 2 d. Data are means ± se (n = 3, more than 80 seedlings for each biological replicate). Ler, Landsberg erecta. E, Fluorescence images of ROS (as indicated by H2DCFDA) and chlorophyll in the cotyledons of 5-d-old etiolated seedlings followed by 2 d of white light. Bars = 200 μm.