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bioRxiv · 10.1101/2022.02.10.479914

Architecture of the human erythrocyte ankyrin-1 complex

Vallese, F.·Kim, K.·Yen, L. Y.·Johnston, J. D.·Noble, A. J.·Cali, T.·Clarke, O. B.
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Abstract

The stability and shape of the erythrocyte membrane is provided by the ankyrin-1 complex, but how it tethers the spectrin-actin cytoskeleton to the lipid bilayer and the nature of its association with the band 3 anion exchanger and the Rhesus glycoproteins remains unknown. Here we present structures of ankyrin-1 complexes purified from human erythrocytes. We reveal the architecture of a core complex of ankyrin-1, the Rhesus proteins RhAG and RhCE, the band 3 anion exchanger, protein 4.2 and glycophorin A. The distinct T-shaped conformation of membrane-bound ankyrin-1 facilitates recognition of RhCE and unexpectedly, the water channel aquaporin-1. Together, our results uncover the molecular details of ankyrin-1 association with the erythrocyte membrane, and illustrate the mechanism of ankyrin-mediated membrane protein clustering.

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Vallese, F., Kim, K., Yen, L. Y., Johnston, J. D., Noble, A. J., Cali, T., Clarke, O. B.. 2022-02-10. Architecture of the human erythrocyte ankyrin-1 complex. https://doi.org/10.1101/2022.02.10.479914

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