Cryo-EM structures of full-length GlyR in multiple conformational states.a Ion permeation pathway generated with HOLE60 for GlyR–Apo (salmon red), GlyR–Gly/PTX (deep teal) and GlyR–Gly (slate blue). For clarity, the cartoon representation of only two non-adjacent subunits are shown. Green and purple spheres define radii of 1.8–3.3 Å and >3.3 Å, respectively. The residues located at various pore constrictions are shown as sticks. b The pore radius is plotted as a function of distance along the pore axis. The dotted line indicates the approximate radius of a hydrated chloride ion, which is estimated at 2.26 Å. c A view of M2 helices from the extracellular end for the three GlyR conformations. Positions Leu9′ and Pro-2′ are shown in ball-and-stick representation and the corresponding distances between Cα are given in Å.
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