G Far‐Western blot of GRB2‐SH3 domains binding to full‐length SHP1. HA IPs from empty vector or HA‐SHP1‐transfected HEK293 cells were subjected to far‐Western blotting using recombinant GST‐tagged N ‐or C‐SH3 domains of GRB2. GST alone served as a background control. Blots were re‐probed for SHP1 loading for normalization of anti‐GST signals. Data shown are representative of three independent experiments. 