The Gab1 MBD interacts with Tpr-Met and impairs Gab1 phosphorylation. (A and B) Independent transient transfection of HEK 293 cells with Tpr-Met or/and HA-tagged wt MBD of Gab1, or a mutant of lacking the Grb2- and Met-binding motifs. (A) Top, Tpr-Met proteins were immunoprecipitated and subsequently blotted with phosphotyrosine antibody to detect phosphorylated Tpr-Met and then stripped and reblotted for detection of Tpr-Met using antibody 144, or blotted with HA for detection of the MBD proteins. Bottom, Western analyses of total cell lysates (TCL) show the levels of HA-tagged MBD or tubulin expression. (B) Top, Tpr-Met proteins were immunoprecipitated and blotted with Tpr-Met–specific antibody. Bottom, Western analyses of TCL show the expression level of HA-tagged MBD, phospho-Gab1, Gab1 proteins, or tubulin.