Crystal structure of Na+, K(+)-ATPase in the Na(+)-bound state

Research output: Contribution to journalArticle


The Na(+), K(+)-adenosine triphosphatase (ATPase) maintains the electrochemical gradients of Na(+) and K(+) across the plasma membrane--a prerequisite for electrical excitability and secondary transport. Hitherto, structural information has been limited to K(+)-bound or ouabain-blocked forms. We present the crystal structure of a Na(+)-bound Na(+), K(+)-ATPase as determined at 4.3 Å resolution. Compared with the K(+)-bound form, large conformational changes are observed in the α subunit whereas the β and γ subunit structures are maintained. The locations of the three Na(+) sites are indicated with the unique site III at the recently suggested IIIb, as further supported by electrophysiological studies on leak currents. Extracellular release of the third Na(+) from IIIb through IIIa, followed by exchange of Na(+) for K(+) at sites I and II, is suggested.


  • Maria Nyblom
  • Hanne Poulsen
  • Pontus Gourdon
  • Linda Reinhard
  • Magnus Andersson
  • Erik Lindahl
  • Natalya Fedosova
  • Poul Nissen
External organisations
  • Aarhus University
Research areas and keywords


  • Animals, Cell Membrane, Crystallography, X-Ray, Models, Molecular, Mutation, Protein Binding, Protein Structure, Secondary, Protein Structure, Tertiary, Sodium, Sodium-Potassium-Exchanging ATPase, Swine, Journal Article, Research Support, Non-U.S. Gov't
Original languageEnglish
Pages (from-to)123-7
Number of pages5
JournalScience (New York, N.Y.)
Issue number6154
Publication statusPublished - 2013 Oct 4
Publication categoryResearch
Externally publishedYes