Impaired thrombopoietin and integrin signaling in Shp2-deficient megakaryocytes. Mature bone marrow-derived megakaryocytes from (A) Shp1 KO, (B) Shp2 KO, and litter-matched WT (Shp1 WT and Shp2 WT) mice were stimulated with 50 ng/mL thrombopoietin (Tpo) for 10 min at 37°C. Whole cell lysates (WCLs) were western blotted with anti-phospho-Erk1/2 (p-Erk1/2), -pan Erk1/2 (Erk1/2), and -Src p-Tyr418 antibodies. Representative blots from n = 3 independent experiments/genotype. (C) WCLs of Shp2-deficient megakaryocytes were western blotted with anti-Mpl receptor and -Erk1/2 antibodies (n = 3 independent experiments/genotype). WCLs prepared of bovine serum albumin (BSA) nonadherent and fibrinogen (fib)-adhered (D) Shp1 KO, (E) Shp2 KO, and litter-matched WT megakaryocytes were western blotted with anti-p-Erk1/2, -Erk1/2, and -Src p-Tyr418 antibodies. Representative blots from n = 3 independent experiments/genotype.