Fig. 2: MinD–ATP induces local liposome adhesion to SLBs.

a, Schematic and experimental illustration of liposome flattening on SLBs (both grey) facilitated by MinD (magenta) membrane binding. MinD–ATP addition brings the liposomes close to the SLBs (top; the rows show snapshots with increasing time; the interaction is indicated by magenta curves), allowing the lipid membranes to adhere (centre; chain symbols). MinD proteins are excluded from the liposome–SLB contact areas (bottom). Fluorescence snapshots show MinD (magenta) and liposome membrane (grey) at the subsequent stages of liposome attachment. Scale bar, 5 μm; b, Liposome flattening requires both MinD and ATP (right), and no flattening is observed when only MinD (left) or only ATP (centre) is present. Scale bar, 5 μm. c, Characterizing liposome flattening by contact angle θ (defined in b). The actual contact angle of an ideal sphere should be 180°, but due to limited image resolution, the measured contact angle of a perfect sphere would be around 155° (Methods). Liposomes did not substantially deform in Min buffers with different MgCl₂ concentrations, Min buffer with ATP addition (2.5 mM) and Min buffer with MinD addition (2.5 µM). However, θ substantially decreased in the simultaneous presence of MinD (2.5 µM) and ATP (2.5 mM). From left to right, the database for the measurements is n = 19, one experiment; n = 45, three experiments; n = 44, two experiments; n = 73, four experiments; n = 35, two experiments; n = 60, three experiments. For the box figure, whiskers are 1.5× the interquartile range, the median is shown as a black line and the mean is shown as a red line. Formation of Min quasi-stationary pattern in vitro and in silico. d, Schematic of MinE persistent binding model^{21,38,39,40,41}. MinD–ATP (magenta) autocatalytically binds to the membrane, where it can bind MinE (green). MinE induces the dissociation of MinD from the membrane. MinE is present on the membrane not only as a part of a MinDE complex ① but also as a MinE dimer isolated from MinD ②. e, Quasi-stationary MinD (left) and MinE (right) protein patterns as observed in experiments (top) and simulations (bottom; Methods). The simulations show the local protein concentration, whereas the experiments show the protein fluorescence intensity. Scale bar, 10 μm.