Fig. 6. Inhibition of SOCE and I_crac by ML-9 is due to inhibition of Stim1 rearrangement. (A) SOCE experiments were performed in which ML-9 was added following restoration of extracellular Ca²⁺ as described in Fig. 3C. As described in Fig. 3D, SOCE following ML-9 addition as a percentage of the untreated control was calculated and is plotted as a function of ML-9 concentration for HEK293 cells overexpressing unconjugated EYFP (black squares) and EYFP-Stim1 (blue triangles). (B) TIRFM fluorescence intensity (black trace) and relative intracellular Ca²⁺ concentration (360/380 ratio; blue trace) were measured simultaneously in the same cell. Ca²⁺ stores were depleted with thapsigargin (Tg; 2 µM) in the presence of 1.8 mM extracellular Ca²⁺, and 100 µM ML-9 was added 15 minutes later. (C) For the data shown in panel B, the TIRFM (black trace) and 360/380 (blue trace) values beginning just before ML-9 addition were normalized to the same minimum and maximum values.