Fig. 2.

Activating currents from the Ano1₍₀₎ΔEAVK splice variant have a higher EC₅₀ of Ca²⁺ dependence than Ano1₍₀₎. A: representative Cl⁻ current traces activated by a voltage step to +80 mV, recorded from HEK293 cells transfected with Ano1₍₀₎ (left) or Ano1₍₀₎ΔEAVK (right), and dialyzed with intracellular Ca²⁺ concentrations ([Ca²⁺]_i) ranging from 100 to 3,000 nM as indicated by the spectrum. Dotted line; 0 pA/pF. B: Cl⁻ currents activated at the 1-s time point (I_ACT) from Ano1₍₀₎ (left) or Ano1₍₀₎ΔEAVK (right), plotted vs. voltage stimulus with 100–3,000 nM [Ca²⁺]_i (spectrum). C: I_ACT from Ano1₍₀₎ (left) or Ano1₍₀₎ΔEAVK (right), plotted as a function of [Ca²⁺]_i at the indicated voltage steps (spectrum). EC₅₀ values (dashed lines): Ano1₍₀₎, 438 ± 7 nM; Ano1₍₀₎ΔEAVK, 746 ± 47 nM; n = 11; *P < 0.05, compared with Ano1₍₀₎ control by an unpaired t-test with Welch’s correction. D–E: voltage of half-activation (V_1/2; D) or slope (δV; E) plotted as a function of [Ca²⁺]_i (P < 0.05, [Ca²⁺]_i as a source of variation of V_1/2 or δV values; P > 0.05, interaction between the EAVK sequence and [Ca²⁺]_i for either V_1/2 or δV by two-way ANOVA with Bonferroni posttest).