Publication Date:
2013-09-21
Description:
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 A resolution. Compared with the K(+)-bound form, large conformational changes are observed in the alpha subunit whereas the beta and gamma 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.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Nyblom, Maria -- Poulsen, Hanne -- Gourdon, Pontus -- Reinhard, Linda -- Andersson, Magnus -- Lindahl, Erik -- Fedosova, Natalya -- Nissen, Poul -- New York, N.Y. -- Science. 2013 Oct 4;342(6154):123-7. doi: 10.1126/science.1243352. Epub 2013 Sep 19.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Centre for Membrane Pumps in Cells and Disease-PUMPkin, Danish National Research Foundation, DK-8000 Aarhus, Denmark.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24051246" target="_blank"〉PubMed〈/a〉
Keywords:
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/genetics
;
Swine
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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