Modes of interaction of Lyn with membranes from ChAc RBCs. (A) Membranes of F2 RBCs from control (C) and ChAc subjects were extracted with Triton X-100 or NaCl (see “RBC morphology, membrane preparation, and membrane cytoskeleton extraction”) and assayed after ultracentrifugation for the presence of Lyn by Western blot (Wb) analysis. The data shown here are obtained with F2 ChAc RBCs. Similar data were obtained with F1 control and ChAc RBCs (data not shown). (B) Membranes of F2 RBCs from control (C) and ChAc subjects were incubated in the presence or absence of GST-Lyn/SH3, GST-Lyn/SH2, cdb3, or phospho (p)–cdb3 and assayed after ultracentrifugation for Lyn in the resulting soluble (S) and pellet (P) fractions for the presence of Lyn by Western blot (Wb) analysis. Similar data were obtained from F1 control and ChAc RBCs (data not shown). The membranes were reprobed with anti–actin antibody as loading control.