Figure 2.

Does JNK catalyze the phosphorylation of GSTpi? To test if active JNK2 was able to phosphorylate GSTpi, incorporation of ³²P from [γ³²P]ATP into GSTpi was monitored. MBP-ATF2 was used as a positive control since it is known to be phosphorylated by JNK. A, An image generated by the PhosphorImager from a P³² phosphor storage screen. B, Coomassie Blue stained SDS-PAGE gel that was utilized to generate the image in A.