Figure 1.

Inhibition of JNK activity by Haplotype A and C GSTpi. Preformed active JNK/ATF2 complexes (in 1:1 molar ratio) were incubated either alone or with 10 μM WT (Haplotype A) or V105/V114 GSTpi (Haplotype C) for 30 min at 25°C. ATP and MgCl₂ were added to initiate the JNK catalytic reaction, and the amount of phosphorylation of ATF2 by JNK was monitored as a function of time by Western blot analysis using antibodies against ATF2 phosphorylated at both Thr-69 and Thr-71 (See footnote on page 3). Representative Western blots are shown. Western blot data was analyzed by densitometry in ImageJ to calculate kinase activity in each reaction (in Luminescence units/min). The rates shown in the bar graphs were an average of at least two independent inhibition assays. A, Inhibition of active JNK1. B, Inhibition of active JNK2.