Figure 7.

GA Partially Rescued sly1 Germination without Reducing RGL2 Protein Levels.

(A) Percentage of germination on indicated GA₃ concentration in ga1-3 biosynthesis mutant (25 months old), sly1-10 (5 months old, #13), after-ripened (A) sly1-2 (26 months old, #21), dormant (D) sly1-2 (0.5 months old, #35), and sly1-t2 (0.5 months old, #12; 18 months old, #2). Germination was calculated based on cotyledon appearance. Age of the stock is shown below the line (months). Error bars show se (n = 30 to 60).

(B) Percentage of radicle emergence determined during time-course experiment examining RGL2 protein accumulation in the presence of 10 μM GA₃ using the same seed lots used in (A) except for 0.5-month-old sly1-t2. Radicle emergence was determined at 60, 72, and 84 h at 22°C following 3 d of 4°C.

(C) RGL2 protein expression in the absence and presence of 10 μM GA₃. Protein was extracted from imbibing seeds at indicated time points at 22°C following 3 d at 4°C.

(D) RGL2 mRNA accumulation in the absence and presence of GA₃ during the same time-course experiment in (C). Left panel, RGL2 mRNA; right panel, ACTIN2 mRNA.