FIGURE 7.

Production of differentially phosphorylated forms of CPK28 during recombinant protein production. Proteins were expressed under three different conditions as described under “Experimental Procedures.” Autophosphorylation status of each phosphoform (P⁻, P⁺, and P⁺⁺) was assessed by blotting with pIMAGO and, anti-Thr(P) and anti-Tyr(P) antibodies as indicated. The K91E kinase-dead mutant is shown as a non-phosphorylated control. Approximately 500 ng of protein was loaded in each lane. IB, immunoblot; CBBG250, Coomassie Brilliant Blue G-250.