FIGURE 3.

S100A14 associates with HER2. A and B, S100A14 binds HER2 in a Ca²⁺-dependent manner. Cell lysates from BT474 (A) or SK-BR3 (B) were incubated with anti-S100A14 antibody or IgG in the presence of either Ca²⁺ or EGTA. The samples were examined by Western blotting using anti-S100A14 antibody or anti-HER2 antibody. C, nickel-nitrilotriacetic acid pull-down assays were performed by incubation of immobilized His-tagged recombinant Myo117 or immobilized His-tagged S100A14 with MDA-MB-453 cell lysates. Bound S100A14 and HER2 were detected by Western blotting using specific antibodies. D, co-IP experiments in HEK 293T/17 cells. FLAG-HER2 and GST-S100A14 were cotransfected into HEK 293T/17 cells as indicated, and cell lysates were then immunoprecipitated using anti-FLAG® M2 affinity gel. The immunoprecipitates were examined by Western blotting (IB) using specific antibodies. Input represented 5% of cell lysates used in the co-IP experiment.