Fig. 3.

The effect of Bcl-2 overexpression on the [Ca²⁺]_ER of MCF-7 cells. (a) Comparison of [Ca²⁺]_ER in neo (red), Bcl-2 (blue), and Bcl-2 also overexpressing SERCA2b (green) cells. Each trace represents the average of more than five cells. Emission ratios were converted into [Ca²⁺], as described in Materials and Methods. Thapsigargin was added at time t = 0 in the absence of external Ca²⁺ to prevent Ca²⁺ influx due to capacitative Ca²⁺ entry. (b) Leakage rate of Ca²⁺ from the ER as a function of [Ca²⁺]_ER for Bcl-2 (blue), neo (red), and Bcl-2 overexpressing SERCA2b (green) cells.