The

SHP1 gene mutation led to elevated tyrosine phosphorylation of the Syk kinase and the Gab2 docking protein.Bone marrow–derived macrophages from me^v/me^vand wild-type (+/+) mice were generated, starved, and stimulated by β₁- integrin cross-linking as detailed in “Materials and methods.” Anti-Gab2 immunoprecipitation was conducted followed by antiphosphotyrosine Western blotting. The membrane was stripped and reprobed with anti-SHP-2, Syk, and Gab2 Abs. Shown in the figure is a representative of 2 independent experiments.