GSK2606414 (PERKi) inhibits PERK kinase activity in the presence of physiological levels concentrations of ATP.
A, SDS-PAGE analysis of reactions containing 5 nm PERK kinase domain, 2.5 μm eIF2α N-terminal lobe, and 1 mm ATP, incubated for 60 min in the presence of the indicated concentrations of PERKi. The phosphorylated (eIF2αP) and unphosphorylated forms of eIF2α are noted. B, as in A except the reactions contained 10 μm ATP. C, nonlinear regression analysis of the relationship between eIF2α phosphorylation and PERKi concentration in A and B.