Fig. 9. PTP inhibition affects long lasting PDGF signaling. 1x10⁶ NIH3T3 cells were serum starved for 24 hours, then stimulated with 30 ng/ml PDGF-BB for the indicated times. (A) PDGF-r was immunoprecipitated from lysates, and an antiphosphotyrosine immunoblot was performed. Equalisation was checked by stripping the blot and reprobing with anti-PDGF-r antibodies. The ratio between the densitometric analyses of anti-phosphotyrosine and anti-PDGF-r signals is shown. (B) Lysates were used for the PI3K assay as reported in the Materials and Methods.