In the cryoEM 3D reconstructions, the TMD appears more stable than the highly mobile CD. The IF and OF states extracted from the bovine AE1 cryoEM maps feature the 7 + 7 TM inverted repeat fold architecture, observed in several SLC4, SLC26, and SLC23 proteins11,12,13,14,16,19....
Structure and mechanism of the uracil transporter UraA. Nature 472, 243–246 (2011). 19. Geertsma, E. R. et al. Structure of a prokaryotic fumarate transporter reveals the architecture of the SLC26 family. Nat. Struct. Mol. Biol. 22, 803–808 (2015). 20. Alguel, Y. et al. ...