view article
Figure 7
Single-particle cryo-EM structure of an unorthodox AQP11. (a) Representative class averages of AQP11. (b) Cryo-EM map of AQP11 in LMNG micelles. (c) Secondary structure of AQP11, which has a novel topology comprising seven transmembrane helices with an additional N-terminal helix, H0. (d) Trimeric structure of AQP11 (PDB ID 9vxw) (Suzuki et al., 2026View full citation) shown from side and luminal views. (e) Monomeric conformation of AQP11 shown from luminal view, highlighting the ar/R filter residues. (f) Comparison of ar/R selectivity filter residues of AQP11 and AQP4. Key residues are shown in stick and sphere representation. (g) Structural comparison of the AQP11 protomer and AQP4 (PDB ID 2zz9), with AQP11 shown in rainbow coloring and AQP4 in white. (h) Distinct helix position of AQP11 relative to AQP4; red arrows indicate differences in the helix arrangement between the two structures. (i)–(k) Enlarged views of the pore regions with NPC/NPA motifs and ar/R filters for (i) AQP11, (j) AQP4 (PDB ID 2zz9) and (k) AQP7 (PDB ID 8y8v) (Kozai et al., 2025View full citation). Small red spheres represent water molecules in the AQP4 pore (j).

IUCrJ
Volume 13| Part 4| July 2026|
ISSN: 2052-2525
https://doi.org/10.1107/S2052252526003234