Figure 5.

Free-energy landscapes of the GluA2 LBD along $\left({\xi }_3,{\xi }_4\right)$. (A) Definition of a reaction coordinate related to hydrogen-bonding interactions between the D1 and D2 lobes. ${\xi }_4$ describes the distance between the COMs of Y450-G451 in the D1 lobe and D651-S652 in the D2 lobe. ${\xi }_1$ is also shown for comparison with ${\xi }_4$. The free-energy landscapes along ${\xi }_3$ and ${\xi }_4$ for flipped (B) and unflipped (C) conformations are shown. White circles represent the corresponding crystal structures. A white triangle represents the average structure of the semiclosed state. The red dashed arrow on the landscape for T686A-Glu represents the direction along the reduced coordinate ${\xi }_{34}=0.26{\xi }_3-0.74{\xi }_4$. To see this figure in color, go online.