Extended Data Fig. 9: NC1 activation of TRPM4 per se is not affected by calcium.
From: Persistent activation of TRPM4 triggers necrotic cell death characterized by sodium overload
a, b, c, The conductance-voltage relation of whole-cell hTRPM4 current in HEK293T-TRPM4-EGFP cells treated vehicle or 1 μM NC1 with different concentrations of EGTA (0, 1, 10 mM) added in the patch pipette solutions. d, Statistics of whole-cell hTRPM4 current density at +100 mV in a, b, c. e, The current density-voltage relation of whole-cell hTRPM4 current in HEK293T-TRPM4 cells treated vehicle or 1 μM NC1 in the presence or absence of 1 μM intracellular Ca2+. NC1 further increase the current amplitude of TRPM4 with the presence of intracellular calcium. f, g, Dose-dependent cytotoxicity of NC1 in MCF7 cells pretreated with calcium ion chelators BAPTA-AM (f) or EGTA-AM (g). h, i, The whole-cell current-voltage relation of hTRPM4 E828K (h) or E1068Q (i) mutant expressed in HeLa cells (right panel). Summary data showing the maximum amplitude of currents activated by NC1 at +100 mV (left panel). j, Dose-dependent cytotoxicity of NC1 in TRPM4-KO MCF7 cells with re-expression of TRPM4 WT or mutants above. Viability data represent mean ± s.d. of n = 3 replicates from one representative of three independent experiments. Electrophysiological data represent mean ± sem of (n = 7 for a, e and i, 5 for b and h, 6 for c) independent cells. Immunoblot data show one representative out of three replicates from three independent experiments. Two-way ANOVA (GraphPad Prism 9.0.0) for statistics in d, h, i.
