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1783707 
Journal Article 
Crystal structure of the sodium-potassium pump 
Morth, JP; Pedersen, BP; Toustrup-Jensen, MS; Sorensen, TLM; Petersen, J; Andersen, JP; Vilsen, B; Nissen, P 
2007 
1 
Nature
ISSN: 0028-0836
EISSN: 1476-4687 
450 
7172 
1043-U6 
18075585 
WOS:000251579900078 
The Na+, K+-ATPase generates electrochemical gradients for
sodium and potassium that are vital to animal cells, exchanging three sodium ions for two
potassium ions across the plasma membrane during each cycle of ATP hydrolysis. Here we present
the X- ray crystal structure at 3.5 angstrom resolution of the pig renal Na+, K 1- ATPase with
two rubidium ions bound ( as potassium congeners) in an occluded state in the transmembrane part
of the alpha-subunit. Several of the residues forming the cavity for rubidium/potassium occlusion
in the Na+, K+-ATPase are homologous to those binding calcium in the Ca2+- ATPase of sarco( endo)
plasmic reticulum. The beta- and gamma-subunits specific to the Na+, K+- ATPase are associated
with transmembrane helices alpha M7/alpha M10 and alpha M9, respectively. The alpha-subunit
corresponds to a fragment of the V- type ATPase c subunit. The carboxy terminus of the alpha-
subunit is contained within a pocket between transmembrane helices and seems to be a novel
regulatory element controlling sodium affinity, possibly influenced by the membrane potential.