Figure 2: PI(3,5)P2 activates endogenous TRPML-like currents (ITRPML1-L) in the endolysosomal membranes.

(a) An endogenous inwardly rectifying ITRPML1-L activated by PI(3,5)P2 (10 μM) in a vacuole isolated from a non-transfected Cos-1 cell. (b) Large PI(3,5)P2-activated ITRPML1-L in a vacuole isolated from wild-type (WT) human skin fibroblast cell. (c) Lack of significant PI(3,5)P2-activated ITRPML1-L in a vacuole isolated from a human ML4 (TRPML1−/−) skin fibroblast cell. (d) Endogenous PI(3,5)P2-activated ITRPML-L in WT and TRPML1−/− human fibroblasts. Data are presented as the mean ± s.e.m.; the n numbers are in parentheses. Statistical comparisons were made using analysis of variance: ***P<0.001.