Fig 2. Homomeric ASIC currents are insensitive to PI(4)P and PI(4,5)P₂.

(A) ASIC1a currents evoked by repetitive rapid extracellular pH change from 7.4 to 6.0 for 10 s with time intervals of 120 s in cells expressing LDR and either PJ-Dead, PJ-Sac, INPP5E, or PJ. Rapamycin (1 μM) was bath-applied for 60 s, and then normal extracellular solution was perfused for 10 s right before the second pulse to minimize possible side effects of rapamycin. Dashed line indicates the zero current level. (B) Relative current density measured for the cells in (A) (n = 6, respectively). Current density of each pulse was divided by that of the first pulse. There is no statistical significance with two-way ANOVA followed by Bonferroni post-hoc test. (C) ASIC2a or ASIC3 current traces evoked by pH drop to 4.5 or 6.0 for 10 s. (D) Relative current density measured for the cells in (C) (n = 6, respectively). There is no statistical significance with two-way ANOVA followed by Bonferroni post-hoc test. Data are mean ± SEM.