National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Disease (NIH/NIDDK)
R01DK077162
米国
National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Disease (NIH/NIDDK)
R01GM071940
米国
引用
ジャーナル: Commun Biol / 年: 2022 タイトル: CryoEM structures of anion exchanger 1 capture multiple states of inward- and outward-facing conformations. 著者: Hristina R Zhekova / Jiansen Jiang / Weiguang Wang / Kirill Tsirulnikov / Gülru Kayık / Hanif Muhammad Khan / Rustam Azimov / Natalia Abuladze / Liyo Kao / Debbie Newman / Sergei Yu Noskov ...著者: Hristina R Zhekova / Jiansen Jiang / Weiguang Wang / Kirill Tsirulnikov / Gülru Kayık / Hanif Muhammad Khan / Rustam Azimov / Natalia Abuladze / Liyo Kao / Debbie Newman / Sergei Yu Noskov / D Peter Tieleman / Z Hong Zhou / Alexander Pushkin / Ira Kurtz / 要旨: Anion exchanger 1 (AE1, band 3) is a major membrane protein of red blood cells and plays a key role in acid-base homeostasis, urine acidification, red blood cell shape regulation, and removal of ...Anion exchanger 1 (AE1, band 3) is a major membrane protein of red blood cells and plays a key role in acid-base homeostasis, urine acidification, red blood cell shape regulation, and removal of carbon dioxide during respiration. Though structures of the transmembrane domain (TMD) of three SLC4 transporters, including AE1, have been resolved previously in their outward-facing (OF) state, no mammalian SLC4 structure has been reported in the inward-facing (IF) conformation. Here we present the cryoEM structures of full-length bovine AE1 with its TMD captured in both IF and OF conformations. Remarkably, both IF-IF homodimers and IF-OF heterodimers were detected. The IF structures feature downward movement in the core domain with significant unexpected elongation of TM11. Molecular modeling and structure guided mutagenesis confirmed the functional significance of residues involved in TM11 elongation. Our data provide direct evidence for an elevator-like mechanism of ion transport by an SLC4 family member.