Fig. 4: Structure of α7-nAChR/WTX complex in membrane environment.

a General view of the complex from the top. nAChR subunits are individually colored in a blue-green spectrum; five WTX molecules at the interfaces of two adjacent receptor’s subunits are shown by red. b Side view of the complex. Carbon atoms of the membrane lipids are colored as follows: POPC and POPE, pale yellow; cholesterol, pale orange. Other lipid atoms: phosphorus, orange; oxygen, red; nitrogen, blue. Lipids of the proximal part of the membrane are removed for clarity. Membrane-interacting residues of WTX are colored by forest green. c Zoomed-in picture of WTX interacting by the loops II and III with α7-nAChR and by loop I, head-1, and N- and C-termini with the membrane. d Snapshot of WTX-nAChR and WTX-membrane interactions. α7-nAChR primary (+) and complementary (−) subunits are shown as blue and cyan cartoon, respectively; WTX residues that interact with receptor (red background) or membrane (green background) are shown. Details of the WTX membrane interactions are given in Fig. 5 (from the point of view depicted by green arrow). e Pore profile of the α7-nAChR channel for the given MD snapshot. Blue volume corresponds to water-permeable cavity; green—to the impermeable (e.g., closed pore). Graphs show pore radius profiles: open pore in α7-nAChR with epibatidine and PNU-120596 (PDB ID: 7KOX¹⁶)—green; closed pore in α7-nAChR with α-Bgtx (PDB ID: 7KOO¹⁶)—red; and the pore in our model α7-nAChR/WTX—blue.