Volume 114, Issue 1, Pages 146-157 (January 2018) Intrinsic Curvature-Mediated Transbilayer Coupling in Asymmetric Lipid Vesicles  Barbara Eicher, Drew Marquardt, Frederick A. Heberle, Ilse Letofsky-Papst, Gerald N. Rechberger, Marie-Sousai Appavou, John Katsaras, Georg Pabst  Biophysical Journal  Volume 114, Issue 1, Pages 146-157 (January 2018) DOI: 10.1016/j.bpj.2017.11.009 Copyright © 2017 Biophysical Society Terms and Conditions

Figure 1 DSC cooling thermograms of POPE/POPC∗ mixtures. Numbers adjacent to the heat-capacity (cP) maxima indicate the given χPOPE. The inset shows the concentration dependence of the TM values of LUVs and MLVs, which served as controls (Fig. S2). To see this figure in color, go online. Biophysical Journal 2018 114, 146-157DOI: (10.1016/j.bpj.2017.11.009) Copyright © 2017 Biophysical Society Terms and Conditions

Figure 2 Gel area-per-lipid (AL) calibration curve determined from WAXS. Data on an absolute temperature scale are shown in Fig. S8. Biophysical Journal 2018 114, 146-157DOI: (10.1016/j.bpj.2017.11.009) Copyright © 2017 Biophysical Society Terms and Conditions

Figure 3 (A) Vesicle size (symbols) as a function of temperature and corresponding αST, and αALT (dashed lines) for POPEout/POPCin (D/A = 2) aLUVs (filled symbols) and POPE∗ LUVs (open symbols), as determined from DLS. The dash-dotted gray line represents αALT values reported from scattering experiments (50). (B) Corresponding cryo-TEM images of POPEout/POPCin (upper) and POPCout/POPEin (lower) measured at 4°C (left column) and 35°C (right column). To see this figure in color, go online. Biophysical Journal 2018 114, 146-157DOI: (10.1016/j.bpj.2017.11.009) Copyright © 2017 Biophysical Society Terms and Conditions

Figure 4 DSC cooling scans of POPCout/POPEin (A) and POPEout/POPCin (B) aLUVs (D/A = 3) (solid lines). Transitions of the corresponding scrambled LUVs are shown as gray dashed lines. (Insets) Schematics of leaflet structure. See Fig. S7 for the corresponding D/A = 2 data. To see this figure in color, go online. Biophysical Journal 2018 114, 146-157DOI: (10.1016/j.bpj.2017.11.009) Copyright © 2017 Biophysical Society Terms and Conditions

Figure 5 Wide-angle scattering and lipid packing of gel-phase aLUVs. (A) Comparison of WAXS data for aLUVs (solid line) and scrambled LUVs (dashed line) fitted by Gaussians. The inset compares the average χD of aLUVs and LUVs. (B) Comparison of POPEout/POPCin (dashed line; T = 10°C) and POPCout/POPEin (solid line; T = 5°C) WAXS data fitted by Gaussians. The POPEout/POPCin data contain an additional broad peak originating from fluid hydrocarbons (inset). (C and D) AL values for POPCout/POPEin (C) and POPEout/POPCin aLUVs (D) as a function of temperature (symbols). Solid lines correspond to theoretical AL values of the outer leaflet and the dashed line to theoretical AL values of the inner leaflet calculated for a given leaflet composition. See Fig. S8 for the corresponding D/A = 2 data. To see this figure in color, go online. Biophysical Journal 2018 114, 146-157DOI: (10.1016/j.bpj.2017.11.009) Copyright © 2017 Biophysical Society Terms and Conditions

Figure 6 Joint analysis of SAXS (upper) and SANS (lower) data for POPCout/POPEin aLUVs at 35°C. Solid lines show best fits using the aSDP model (dashed line, POPCout/POPEin; solid line, POPCout/POPE-d31in). (Insets) Corresponding electron and neutron scattering-length density profiles. To see this figure in color, go online. Biophysical Journal 2018 114, 146-157DOI: (10.1016/j.bpj.2017.11.009) Copyright © 2017 Biophysical Society Terms and Conditions

Figure 7 Schematic lipid distribution and transbilayer coupling in POPCout/POPEin (A) and POPEout/POPCin aLUVs (B). To see this figure in color, go online. Biophysical Journal 2018 114, 146-157DOI: (10.1016/j.bpj.2017.11.009) Copyright © 2017 Biophysical Society Terms and Conditions