CBL is a substrate for SHP-1.

(A-B) Western blot analysis of CBL immunoprecipitates to assay the tyrosine phosphorylation of CBL and to determine protein-protein interactions between CBL and SHP-1 or CRKL following treatment of IgG-sensitized sRBCs in J774A.1 cells expressed by wild-type SHP-1 and catalytically dead mutant SHP-1. J774A.1 lysates prepared from resting cells or cells stimulated with sensitized sRBCs for 5 and 10 minutes were immunoprecipitated with polyclonal anti-CBL antibody and immunoblotted with antiphosphotyrosine antibody (PY-CBL blot), anti-CBL antibody (CBL blot), anti–SHP-1 antibody (SHP-1 blot), and anti-CRKL antibody (CRKL blot). (C) Western blot analysis shows expression of SHP-1 proteins in J774A.1 cells infected with recombinant vaccinia virus: lane 1, no vector; lane 2, empty vector; lane 3, catalytically dead SHP-1 mutant; lane 4, wild-type SHP-1 phosphatase.