Figure 4

Regulation of IR activation through PTP1B and Grb14. In support of our current findings, Figure 4 presents aggregate data based on the results from our previous studies of the IR kinase and PTP1B activities in wild-type, PTP1B KO, and Grb14 KO mice [8, 10, 19]. The IR immunoprecipitates from dark- and light-adapted wild-type, PTP1B^-/-, and Grb14^-/- mice were subjected to IR kinase activity employing poly Glu:Tyr peptide as a substrate (A). PTP1B activity was measured in retinas harvested from the dark- and light-adapted wild-type and Grb14^-/- mice (B). Data are mean ± SD, n = 5, *p < 0.05. The IR kinase activity and PTP1B activity in dark-adapted retinas was set at 100%.