Figure 9. MSL1 gating causes morphological changes in membrane akin to those observed for MscS.

The figure summarizes the results from simulations of closed and open states of MSL1 in a POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) membrane, using a coarse-grained representation (Table 1). (A) The cryo-electron microscopy (EM) structures (blue cartoons) are overlaid with calculated 3D density distributions mapping the morphology of the alkyl chain double layer in each of the molecular dynamics (MD) trajectories (gold volumes), up to 50 Å from the protein surface. Maps were calculated and are represented as in Figure 4. (B) Time-averages of the instantaneous lipid configurations observed in each of the two MD trajectories, mapped across the membrane plane and shown in cross-section. Averages were calculated and are represented as in Figure 5B. The datasets in panels (A) and (B) were symmetrized in accordance with the sevenfold internal symmetry of the channel.