Fig. 3. Evaluation of caged GA₃1–3 stability in vitro and in vivo. (A) Yeast two-hybrid assay. Yeasts expressing GID1a only or GIDa and RGA were treated: (top) with or without 25 μM GA₃ and (bottom) with 25 μM 1–3 pre-irradiated (+light) or not (–light). (B) Germination assay. Ler ga1–3 mutant seeds (n = 30–50) were sown on MS plates containing 25 μM 1–3. The germination status was determined on day 4. Mock represents no treatment. Error bars represent STDV. (C) GFP-RGA response to 1–3 in dark grown root tips. pRGA:GFP-RGA Arabidopsis seedlings (n = 6–8) were treated with paclobutrazol (paclo, 2 μM) overnight and subsequently transferred to MS plates containing paclo (2 μM) and any of the 1–3 (25 μM). Images were taken after 4 hours. Mock represents no treatment. Error bars represent SEM. *Statistical significance (one-way ANOVA with Tukey correction, p < 0.05) from GA₃ (B) or mock (C). (D) Representative images of the data in (C). Red: propidium iodide (PI). Green: GFP-RGA.