(A−D) Cross-correlation matrices for four states (A, closed; B, slightly open; C, partially open; D, fully open) computed using LMI. (E−G) Difference in correlation matrix elements for the (E) slightly, (F) partially, and (G) fully open states with respect to the closed state. RBD regions form highly correlated blocks (D and G), indicating that these residues are largely decoupled from the rest of the protein. Still, signatures of long-distance correlated motion are detectable.