Figure 4.

Two-step separation between S2 and S1. (a) Two steps of S2 exit from the S1 domain: S1 regions that cap S2 domain (purple) are highlighted in a surface representation in green. (b) Pulling force versus displacement of S2 domain (with and without Nrp1). Results shown were averaged over duplicate simulations of the seven models without and with Nrp1. (c) S2-S1 contacts at the cleavage site at the start of the simulation (here model 7 at 0 ns). (d) Shows a schematic picture of the “holding effect” of Nrp1—essentially, Nrp1 binding stabilizes the region it associates with and does not allow the stretching of this region. (S2 is in violet, S1 in green, and Nrp1's primary binding domain b1 in yellow.)