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

Science. 2013 Oct 4;342(6154):123-7. doi: 10.1126/science.1243352. Epub 2013 Sep 19.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Membrane / enzymology
  • Crystallography, X-Ray
  • Models, Molecular*
  • Mutation
  • Protein Binding
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Sodium / chemistry*
  • Sodium-Potassium-Exchanging ATPase / chemistry*
  • Sodium-Potassium-Exchanging ATPase / genetics
  • Swine


  • Sodium
  • Sodium-Potassium-Exchanging ATPase

Associated data

  • PDB/4HQJ