Figure 1.

PE-dependent noncovalent interactions between C- and N-termini in closed rTRPV2. The homo-tetrameric cryo-EM structures of the rTRPV2 channels with or without PE bound at the vanilloid site and in VSLD in DMNG/MSP2N2 nanodiscs in three closed states at 4 °C (PDB ID, 8EKP, 8EKQ and 8EKR, respectively) were utilized for the model. Salt bridges, π interactions, and H-bonds between paired amino acid side chains are denoted in purple, green, and orange, respectively. The specific grid sizes necessary to regulate the least-stable noncovalent interactions in the grids are indicated with black numbers. The least-stable bridge in the biggest thermoring is highlighted in yellow. The total grid sizes and the total grid size-controlled noncovalent interactions between specific C- and N-termini are displayed in cyan and black circles, respectively, for the calculation of the local systematic thermal instability (T_i).