Fig. 3: Membrane binding and remodeling experiments with different CL Species.
From: Cardiolipin dynamics promote membrane remodeling by mitochondrial OPA1
a Co-sedimentation assays of S-OPA1 WT were performed using liposomes containing five different CL species: CL(16:0)4, CL(18:0)4, CL(18:1)4, CL(16:0)2–(18:1)2, and CL(18:2)4. All liposomes share a common composition of 45% POPC, 22% POPE, and 8% L-PI, with the remaining 25% composed of the respective CL species. Supernatant and pellet samples were collected after centrifugation, subjected to SDS-PAGE, and quantified using ImageJ. S supernatant, P pellet. b The assays were performed in triplicate, and the binding activity was quantified from the pellet fractions. Statistical significance was assessed using an unpaired Welch’s t-test based on n = 3 independent experiments comparing binding across various CL-containing liposome compositions. P-values are represented on the graph, and p < 0.05 is considered to be statistically significant. c Remodeled area (μm2) was calculated by measuring the surface area of membrane tubules. Each lipid composition was tested in three independent reconstitution assays, and negative-stain TEM imaging was performed on each replicate. The total remodeled area was calculated per micrograph and a total of 75 negative stain micrographs were analyzed per lipid composition. d S-OPA1 filaments were counted in each micrograph and plotted against the corresponding lipid composition. b–d Error bars represent the standard error of the mean (s.e.m.). Statistical significance was assessed using an unpaired Welch’s t-test with n = 3 independent experiments. P-values are annotated on the graph, and p < 0.05 is considered statistically significant. e Quantification of filament morphology per liposome composition. Each remodeled filament was counted and assigned to one of the three classes: large (cyan), medium (purple), or small (pink). Filament sizes were defined as small at 0–0.01 μm2, medium for 0.01–0.05 μm2, and large if >0.05 μm2. The percentage of each class is calculated per liposome composition and is shown as a stacked bar graph.
