Fig. 3: Protein–lipid interactions identified in IP3R1-ND structure.
From: Cryo-EM structure of type 1 IP3R channel in a lipid bilayer
a IP3R1-ND cryo-EM density map for TM1–TM6 helices of two opposing subunits; the model is depicted as a ribbon and viewed parallel to the membrane plane. Lipids are represented as orange ball-and-stick models and labeled L1–L7. b TMD densities for one subunit are overlaid with the IP3R1-ND model viewed parallel to the membrane plane and rotated ~90° from the position in a. c Zoomed-in views of seven lipid-binding sites (L1–L7) identified in the TM region. Lipids are putatively modeled as phosphatidylcholine (see “Methods” section); the PC models are colored by elements and fit into corresponding cryo-EM densities displayed at 3–5σ cut-off values (gray) and 2–2.5σ (orange mesh). TM helices are depicted as ribbons colored by channel subunit. Residues within 5 Å of the lipid molecules are displayed in a stick representation and labeled.
