Membrane thickness is positively correlated with membrane curvature. (A) Representative membrane surface reconstruction of mitochondria colored by IMM curvedness. (B) Quantification of IMM thickness by curvedness quantile shows that higher curvature significantly correlates with thicker membrane. P values from the Mann–Whitney U test are indicated. *P < 0.05, ***P < 0.005. (C). ATP synthases (highlighted by pink dashed lines) are located at the IMM (orange) with distinct curvature. The left panel shows an ATP synthase positioned at a curved crista tip, and the right panel shows one on a flat crista body. (D) 3D subtomogram average structure of ATP synthase monomer positioned on IMM with its F1 catalytic head and central stalk highlighted by arrows. (E) ATP synthase (outlined by pink dashed lines) and the corresponding membrane patch (cyan) representing its local footprint on IMM (orange). (F) Quantification of average thickness of ATP synthase patches and randomized patches on crista bodies for each mitochondrion. ATP synthase patches show no significant difference in thickness compared with randomized patches. Quantification of ATP synthase patch number n = 984 and randomized patch number n = 984 is shown. (G) 2D histogram of average thickness and log₁₀ (curvedness) for ATP synthase patches and randomized patches on crista bodies. ATP synthase patches show a positive correlation between thickness and curvature.