Figure 1.

CuCl₂ and CdCl₂ induce the activation of 44- and 46-kD protein kinases. Alfalfa roots of hydroponically grown plants were exposed for 30 min to 0, 1, 10, 50, 100, 500, and 1,000 μm CuCl₂ (A) or CdCl₂ (B). In-gel kinase assays were performed with 20 μg of protein extracts using MBP as substrate.