Figure 4: TRPML1 is required for autophagic clearance of damaged mitochondria and removal of excessive ROS.
From: MCOLN1 is a ROS sensor in lysosomes that regulates autophagy
(a) Effects of ML-SI3 (10 μM) co-administration on the accumulation of PARKIN-positive puncta (red) induced by CCCP treatment (10 μM for 3 h) followed by 1 h recovery (without CCCP) in PARKIN stable cells. Scale bar, 10 μm. (b) Quantitative analysis of ML-SI3 and ML-SI4 effects on the clearance of PARKIN puncta. (c) Effects of CCCP treatment on mitochondrial membrane potential monitored by JC-1 fluorescent dyes in WT and ML-IV fibroblasts. After CCCP (10 μM for 3 h) treatment, removal of CCCP for 1 h led to repolarization (re-energization) of mitochondrial membrane potential (green, J-monomer; de-energized; red, J-aggregates; energized) in WT but not ML-IV cells. Scale bar, 10 μm. (d) The ratio of red to green fluorescence of JC-1 was quantified for >30 randomly-selected cells. Data are presented as mean±s.e.m. *P<0.05, ANOVA. (e) Basal ROS levels in WT, ML-IV and NPC fibroblasts. (f) Effect of ML-SI4 (10 μM) on ROS levels measured by CM-H2DCFDA (green) imaging in HeLa cells. Scale bar, 50 μm. (g) Quantification of results shown in f. Means are shown with s.e.m.; *P<0.05, ANOVA.
