Figure 1.

PSG17N binds to the extracellular loop 2 of murine CD9. Cobalt chelate beads were incubated with GFP-His (lane 1), CEACAM1a[1-4]-His (lane 2) or PSG17N-Myc-His (lanes 3 and 4) used as baits. The beads were then incubated with GST-CD9EC2 (lanes 1-3) or the same construct carrying the triple mutation SFQ (173-175) to AAA (GST-CD9EC2-TM) (lane 4). After several washes, the proteins were eluted with a buffer containing 290 mM imidazole, separated on a 4-20% NuPAGE gel, and detected by Western blot by using an anti-CD9 antibody.