Go 6983 is a PKC inhibitor with IC50 values of 7, 7, 6, 10, and 60 nM for PKCα, PKCβ, PKCγ, PKCδ, and PKCζ, respectively. Go 6983 has antitumor activity, cardiovascular protection, and protein kinase C inhibition.

PKCγ:6 nM, PKCβ:7 nM, PKCα:7 nM, PKCδ:10 nM, PKCζ:60 nM, PKCμ:20000 nM

Phosphorylation reactions are carried out in a total volume of 100 μL, containing buffer C (50 mM Tris-HCl, pH 7.5, 10 mM β-mercaptoethanol), 4 mM MgCl2, 10 μg PS, 100 nM TPA, 5 μL of a Sf158 cell extract as a source of recombinant PKCμ or of Sf9 cell extracts as a source of other recombinant PKC isoenzymes, 10 μg of syntide 2 as substrate, and 35 μM ATP containing 1 μCi [γ-32P]ATP. In some experiments, PS and TPA are omitted or various inhibitors at concentrations indicated in the text are added. After incubation for 10 min at 30°C, the reaction is terminated by transferring 50 μL of the assay mixture onto a 20 mm square piece of phosphocellulose paper, which is washed 3 times in deionized water and twice in acetone. The radioactivity on each paper is determined by liquid scintillation counting.