FIG 4.

ADAM10, but not ADAM17, is involved in Map-dependent activation of pERK. (A and B) Map impact on ADAM17 and ADAM10 sheddase activity. HeLa cells were transfected with TGF-α–AP-encoding (for monitoring ADAM17) (A) or BTC-AP-encoding (for monitoring ADAM10) (B) plasmids. Cells were then infected with the indicated EPEC strains for 30 min at 37°C, and the levels of sheddase activity were determined as described in Materials and Methods. Each experiment was performed in triplicate, and results are means and SE from 3 independent experiments. (C) Effects of ADAM10 silencing on pERK levels. HeLa cells were transfected with either ADAM10 siRNA or control (scrambled) siRNA, as described in Materials and Methods. Cells were then infected with the indicated EPEC strains for 30 min at 37°C, lysed, and subjected to SDS-PAGE followed by Western blotting for determining pERK levels. Results are means and SE from 3 independent experiments. ***, P < 0.0005; **, P < 0.005; *, P < 0.05; ns, nonsignificant (P > 0.05).