Figure 3.

Analysis of membrane-mediated exit paths. (A) The coordinate Q_ij is defined as the x-y distance between the COM of PK, shown as sticks and colored by atom type, and the line that connects the centers of mass of helix i and helix j. LP1 is not shown here for clarity. (B) The expectation values of the interaction energy between PK and TSPO (blue) and between PK and the membrane (black) are shown as a function of Q. In each case, the solid line shows Q₁₂, and the dashed line shows Q₂₅. The shaded region indicates the standard error over the ensemble of measurements at each Q-value. (C) Probability curves projected onto Q₁₂ for simulations initialized in Pose D1 (blue) and D2 (orange) are shown. Q₁₂-values of the starting structures are marked with asterisks. (D) Poses from transition pathways with Q ≈ 0 are shown. These poses are also labeled in the CSN of Fig. 2. Phe46 is shown in purple, and Trp50 is shown in orange. (E) A set of poses along the Q₁₂ pathway colored from bound (red) to unbound (blue) is given. Top view is shown on the left, and a front view is shown on the right. (F) The minimal PK-TSPO distance and the Q₁₂-value are shown for each pose in (E). (G) The z COM position is shown as a function of Q₁₂. The red lines indicate the upper and lower bounds of the membrane as defined by the maximal and minimal z coordinate of the lipid membrane. To see this figure in color, go online.