Figure 3.

Quantification of cER Curvature

(A–D) 3D visualizations of cER curvedness in the indicated strains. Insets in (A) and (D) show cER peaks. (A) WT cell, (B) Ist2-only cell, (C) Scs2/22-only cell, (D) Tcb1/2/3-only cell. (E) Quantification of cER curvedness, shown as an exceedance plot. The shaded lines represent the average across all MCS ± SE for each bin (1 nm^-1.). ^∗∗ and ^∗∗∗ indicate, respectively, p < 0.01 and p < 0.001 by unpaired t test. N = 6 (WT), 7 (WT HS), 5 (Ist2-only), 5 (Scs2/22-only), and 9 (Tcb1/2/3-only) cER-PM MCS. (F) Enhancement of the rate of lipid extraction by membrane curvature according to a theoretical model. The plot shows the rate of extraction computed for a standard cylindrical lipid (black curve) as well as for lipids of other shapes, such as conical or inverted conical lipids (gray-shaded area between the dashed, black curves). The value of the radius of curvature of the experimentally observed cER peaks is denoted by the dashed red line. $1/R_{curv}$ is equivalent to the curvedness for κ₁=κ₂. See also Figures S3 and S4; Table S1.