Figure 1. Transient exposure to EGTA leads to NOTCH1 receptor activation.

A. MIA PaCa-2 cells were left untreated (-) or treated with EGTA (4mM) for 15min (+). EGTA-containing medium was removed and replaced by normal culture media (Ca²⁺) for the indicated time periods. B. MIA PaCa-2 cells were pretreated (+) or not (-) with DAPT (25μM) for 30min. Cells were then exposed to EGTA (4mM) for 15min (+). EGTA-containing medium was removed and replaced by normal culture media (Ca²⁺) containing DMSO (-) or DAPT (25μM) for 90min. C. MIA PaCa-2 cells were left untreated (-) or treated with EGTA (4mM) for 15min (+). EGTA-containing medium was removed and replaced by normal culture media (Ca²⁺) containing DMSO or actinomycin D (1μg/ml) for the indicated time periods. Western blot analyses were performed using the appropriate antibodies.