Fig. 3: The NBD-dimerized, outward-facing conformation.

A Ribbon representation of the overall structure, colored as in Fig. 1B. Also shown is the cryo-EM density corresponding to the R domain at a contour level of 0.095 (magenta surface). B Zoomed-in view of the R domain, colored as in (A). Hydrogen bonds are represented as dashed lines. C, D conformational changes at the substrate-binding site in the inward-facing, LTC4-bound state (C) versus the outward-facing conformation (D). Residues in green correspond to TMD1, residues in blue correspond to TMD2. E The structure of the substrate-binding site in LTC4-bound conformation, viewed from the extracellular space. TMD1 depicted in green, TMD2 depicted in blue. Hydrogen bonds are represented as dashed lines. F The structure of the substrate-binding site in outward-facing conformation, viewed from the extracellular space.