Figure 1.

Syt1 conformational state obtained by crystallography is relatively stable in a water/ion environment, however interdomain rearrangements can occur at a microsecond scale. (A) Interdomain rotation torsion (top) and bending plain (bottom) angles defining configuration of C2 domains. (B) MD trajectory started from the conformation obtained by crystallography. (C) The same trajectory presented in the space defined by bending and rotation. The initial state 0, a transitional state 1, and a final stable state 2 are labeled. (D) Structures corresponding to the states 0, 1, 2 are shown. Ca²⁺-binding loops are colored green. All the structures are shown with a similar orientation of the C2B domain. (E) MD trajectory started from the stretched state 0s. (F) The same trajectory presented in the space of bending and rotation. (G) The initial state 0s and the final stable state with tightly coupled domains (bottom, state 0). To see this figure in color, go online.