Journal: iScience

Article Title: Mitochondrial F0F1-ATP synthase governs the induction of mitochondrial fission

doi: 10.1016/j.isci.2024.109808

Figure Lengend Snippet: The hydrolase activity of F0F1-ATP synthase compensates for the dysfunction of respiratory chain and prevents mitochondrial fission (A) Mitochondrial network observed with MitoTracker Green by fluorescence microscopy. Left panel: representative images showing the different morphologies of the mitochondrial network. Right panel: Colorimetric representation of the mitochondrial network according to mitochondrial volume Imaris iso-surface rendering. (B) Quantification of mitochondrial volume following OXPHOS inhibition. 3D images analyses were performed using Imaris software (Bitplane). The iso-surface module quantifies the volume of mitochondria in μm 3 . Corresponding percentage of mitochondrial volume of ≤1 μm 3 (fragmented, in violet), ≤20 μm 3 (Normal, in green) and >20 μm 3 (connected, in red). n = 3, analyses were performed on 12 images on three independent biological replicates. Results are presented as means ± SEM. ∗ indicates significant difference from control conditions (Vehicle, Veh). (C) Diagram summary under normal conditions reveal that F0F1-ATP synthase and hydrolase activities work simultaneously in mitochondria with a high proportion of forward action. Schematic representations of the changes in the activity of the complexes and shape of mitochondria following the presence of inhibitors. (D) BMS inhibition of F0F1-ATPase on human fibroblasts. Panels: schematic representation of ATP hydrolase activity following drug application. Activity of mitochondrial F0F1-ATPase (V) normalized to citrate synthase (CS). Fibroblasts were treated in culture conditions 4 h with oligomycin or different concentrations of BMS in order to define the effective BMS concentration that inhibits F0F1-ATPase activity. n = 2, each in duplicate. (E and F) Mitochondrial network following BMS treatments observed using MitoTracker Green by fluorescence microscopy in human control cells, treated for 4 h (E) or 6 h (F) with BMS (30 μM), BMS + R, BMS + A, or BMS + O or Veh. n = 5, analyses were performed on 12 images on four independent biological replicates. Results are presented as means ± SEM.∗ p < 0.05, Mann-Whitney U test. Schematic representations of the changes in the activity of the complexes and shape of mitochondria following the presence of inhibitors with BMS or O.

Article Snippet: 3D images analyses were performed using Imaris software (Bitplane).

Techniques: Activity Assay, Fluorescence, Microscopy, Inhibition, Software, Control, Concentration Assay, MANN-WHITNEY