Fig. 3

Effect of TRPP2-STIM1 interaction on store-operated Ca²⁺ entry (SOCE) in TRPP2 and STIM1 co-expressing HEK293 cells. a-d Summary of data showing changes in Ca²⁺ release (a, c) and SOCE (b, d) in HEK293 cells transfected with TRPP2 siRNA, STIM1 siRNA, STIM1, TRPP2 and/or dominant negative TRPP2 (D511V), and treated by ATP (10 μmol/L), 2APB (100 μmol/L) + ATP (10 μmol/L) and thapsigargin (TG, 2.5 μmol/L) for 8 min in Ca²⁺-free solution. SOCE was evoked by extracellular Ca²⁺ (1 mmol/L) application. Values are shown as the mean ± SEM (n = 3–5). *P < 0.05 compared with scrambled siRNA in each treatment. e Summarized data showing ATP (10 μmol/L)-induced SOCE in HEK293 cells co-expressed with STIM1 and GFP-tagged full-length TRPP2 (GFP-TRPP2) or TRPP2 without N1 (GFP-TRPP2-∆N1, deletion of 2-111aa in TRPP2) or TRPP2 without N2 (GFP-TRPP2-∆N2, deletion of 112-221aa in TRPP2). Values are shown as mean ± SEM (n = 5). ^*P < 0.05 for STIM1 and GFP-TRPP2 or GFP-TRPP2-∆N2 co-expression vs. STIM1 and GFP-TRPP2-∆N1 co-expression