Figure 4
actPTPκ is strongly activated by AsCy5. (A) PTP activity of actPTPκ (400 nM) was measured with pNPP (2 mM, quenched assay) in the absence (DMSO) or presence of the indicated biarsenicals (2 µM) after 60-minute pre-incubations. (B) Dose dependence of actPTPκ activation. PTP activity of actPTPκ (400 nM) was measured with pNPP (2 mM, quenched assay) in the absence (DMSO) or presence of the indicated concentrations of AsCy5 after 30-min pre-incubations. (C) Time dependence of actPTPκ activation. PTP reaction rates of actPTPκ (400 nM) were measured with pNPP (2 mM, continuous assay) in the absence (DMSO) or presence of AsCy5 (2 µM) after indicated pre-incubation times. (D) The activity of wt-PTPκ and actPTPκ (100 nM) was measured with the phosphopeptide DADEpYLIPQQG (100 µM) as a substrate after 30-min of pre-incubation in the absence (DMSO) or presence of AsCy5 (4 µM).
