Fig. 2.
Vesicle absorption in an expanding lipid membrane. The bilayer was expanded with a relative rate of 0.002/s. (A) Dynamics of vesicle absorption, shown as the dependence of the relative projected vesicle area (A/A0) adhered to the bilayer to the bilayer relative area increase (ΔAm/Am0). Am denotes the area of the in-plane membrane, and, A is the out-of-plane lipid area (adhered vesicles); the subscript 0 refers to the beginning of the expansion, and ΔAm denotes the membrane area increase between two consecutive video frames. Three images i, ii, and iii are shown for progressively larger membrane expansion. (B) The rupture of a supported bilayer at a critical strain of 0.02 (dotted line) in the absence of a vesicle reservoir. Black zones indicate rupture locations. (C) The absorption of a GUV (green-yellow) to the expanding planar bilayer (red) shows stages of (i) adhesion, (ii) hemi-fusion zone and expulsion of the GUV content, and (iii, iv) incorporation and diffusion of the vesicle lipids into the bilayer. Scale bars: 20 μm.