We have studied the collective dynamics of leucine-rich repeat (LRR) proteins using an elastic network approximation. The slowest mode of the porcine ribonuclease inhibitor (pRI) protein could be visualized as bending fluctuations of a curved elastic strip leading to a planar opening–closing motion of the horseshoe which largely corresponded to the deformation of the protein on ligand binding. The second slowest mode however exhibited a significant out of plane splaying. The distribution of the lowest eigenvalues of different LRR proteins as a function of their repeat number was found to be close to the dispersion curve obtained from pRI whereas that of the leucine-rich variant (LRV) protein showed considerable deviation. The differing mechanical properties of these structurally similar solenoid proteins may have relevance to their function.
1R0915 Geometrical analysis of leucine-rich repeat proteins
