FIG. 6.
Effect of GADD34 on PP1 inhibition by I-1. The dose-dependent inhibition of phosphorylase phosphatase activity of the skeletal muscle PP1 catalytic subunit was analyzed in the presence (triangles) and absence (diamonds) of 50 nM recombinant GST-GM(1–240) (A) and 30 nM His-GADD34(230–674) (B). Representative curves from three independent experiments that varied by less than 5% are shown. (C) Inhibition of eIF-2α phosphatase activity of the PP1 catalytic subunit by I-1 in the absence and presence of 50 nM His-GADD34(230–674). Results are the sum of three different experiments carried out in duplicate and are shown with standard error bars.