Figure 3
From: Molecular structure and function of myelin protein P0 in membrane stacking
P0ct modulates the properties of lipid structures. (a) The turbidity caused by the presence of P0ct in SUVs somewhat changes depending on the lipid tail saturation degree or the presence of cholesterol. Error bars represent standard deviation. Asterisk: P/L ratio of 1:200. (b) Mixing P0ct with DMPC:DMPG (1:1) SUVs result in X-ray diffraction patterns that display two major Bragg peaks per dataset within the measured s-range. Added P0ct concentrations of 10 and 20 µM are shown as open and filled markers, respectively. A moving average (black line) has been plotted over each dataset, all of which have been offset for clarity. None of the data has been scaled in respect to one another. (c) The mean repeat distances, calculated from the s-values corresponding to the intensity summit of each Bragg peak, plotted as a function of P/L ratio. Linear fits are shown as solid lines for both d1 and d2 distributions. (d) In AFM, P0ct accumulates into supported DOPC:DOPS (1:1) bilayers without spontaneous induction of myelin-like membrane stacking, but increases the local thickness of the membrane by as much as 2 nm. This is evident especially at the edges of the membranes, where the membrane morphology is also changed. The phase difference of the membrane indicates that the mechanical properties of the membrane change in these areas, with a larger change at the edges of the membrane, where P0ct is supposedly most abundant. Height and phase difference graphs are plotted below the images, with the walk path indicated in red. Annotations in phase image walk graphs: m, mica; u, lipid bilayer; p, P0ct-embedded bilayer. Dashed horizontal and vertical dividers have been added to aid comparison.
