Figure 1.

Time course of ³H-ABA binding to the crude ABA-binding proteins extracted with two different methods. Extraction with the buffer containing 0.5% (w/v) Triton X-100 only as the solubilizing medium (●). Extraction first with 0.5% (w/v) Triton X-100 and then with the cold acetone (○). The crude extracts (equivalent to 10 μg of protein) were incubated at 4°C in the buffer containing 70 nm ³H-(±)ABA with the different incubation time. The ³H-ABA binding was counted after each incubation. The time course of ³H-ABA binding during the first 5 h is shown more clearly in the inset. Points in the figure represent the means of three determinations, and those in the inset represent means ± sd of three determinations.