Bcl-2 dependent induction of Ca²⁺ oscillations by TAT-IDP. (A) Diagram of type-1 IP₃R domains designating the origin of the IDP sequence (blue) and the scrambled control sequence (orange), along with the TAT sequence (gray). (B) Immunoblot documenting levels of wild-type and mutant Bcl-2 expressed in Bcl-2–negative WEHI7.2 cells. (C) Number of Ca²⁺ spikes observed per cell in 70 minutes of recordings after adding 2μM of the peptides shown (mean ± SE, 67 cells total). (D) Representative single-cell Ca²⁺ recordings in Bcl-2-positive WEHI7.2 cells (2μM TAT-IDP added at arrow); percentages (mean ± SE) of cells displaying each pattern are based on 3 experiments (90 minutes of recording, average 60 cells per recording). (E) Summary of 2 experiments (mean ± SE) comparing TAT-IDP (2μM)–induced Ca²⁺ responses (90 minutes of recordings, average 60 cells per recording) in Bcl-2–negative versus Bcl-2–positive WEHI7.2 cells. (F) Summary of 3 experiments (mean ± SE) comparing the percentage of cells displaying Ca²⁺ oscillations in response to the addition of 2μM TAT-IDP to WEHI7.2 cells expressing either wild-type Bcl-2 or Bcl-2RS/GG (90 minutes of recording, average 60 cells per recording).