Conformational changes accompanying gating of NaVAb. (A) Close-up views of the S6 helix near Thr206 during the closed, open, and inactivated states of NaVAbΔ28, NaVAb/1–226 (cyan, open; equivalent to NaVAbΔ40) and NaVAb/WT (yellow, inactivated). The main chain of each model is shown in stick format, as is the side chain of Thr206. All other side chains have been removed for clarity. Possible hydrogen bonds are shown as black dashes, and a broken hydrogen bond between the carbonyl of Thr206 and amide of Ile210 is shown in gray in the middle panel. (B) An overlay of NaVAb/1–226 (cyan, open; equivalent to NaVAb 40) and NaVAb/WT (yellow, inactivated) with the view as if one is standing below the membrane and looking upward along the permeation pathway. Voltage sensors have been removed for clarity, and arrows show the conformational changes associated with the transition from the open to the inactivated state. (C) An overlay (as in B) showing a comparison between NaVAb/WT (yellow, inactivated) and NaVAbΔ28 (magenta, closed). As in B, arrows highlight the conformational changes associated with the transition between states.
