SHP-2 associates with distinct regions of G-CSF-R, and Tyr729 is required for the formation of a SHP-2–STAT5 complex. (A) HA–SHP-2 IPs of Phoenix E cells expressing GFP-tagged G-CSF-R mutants. Cells were starved overnight (–) and stimulated for 10 minutes with G-CSF. As a control, expression of GFP–G-CSF-R and SHP-2 in whole cell lysate (WCL) is shown in the lower 2 panels. (B) HA–SHP-2 IPs of Phoenix E cells expressing different G-CSF-R mutants and STAT5 were performed as described for Figure 6A. Lane 7 is an HA-IP in the absence of HA–SHP-2, demonstrating the specificity of the IP.