Flow of ions.

Alpha and beta units.

Na⁺/K⁺-ATPase (also known as the Na⁺/K⁺ pump or sodium-potassium pump) is an enzyme (EC 3.6.3.9) located in the plasma membrane (specifically an electrogenic transmembrane ATPase). It is found in the plasma membrane of virtually every human cell and is common to all cellular life. It helps maintain cell potential and regulate cellular volume. A superscript is a number, figure, or symbol that appears above the normal line of type, at the right or left of another symbol or text. ... A subscript is a number, figure, or indicator that appears below the normal line of type, typically used in a formula, mathematical expression, or description of a chemical compound. ... Ribbon diagram of the enzyme TIM, surrounded by the space-filling model of the protein. ... The Enzyme Commission number (EC number) is a numerical classification scheme for enzymes, based on the chemical reactions they catalyze. ... Drawing of a cell membrane A component of every biological cell, the cell membrane (or plasma membrane) is a thin and structured bilayer of phospholipid and protein molecules that envelopes the cell. ... ATPases are a class of enzymes that catalyze the decomposition of adenosine triphosphate (ATP) into adenosine diphosphate (ADP) and a free phosphate ion. ... Trinomial name Homo sapiens sapiens Linnaeus, 1758 MOSTLY HARMLESS Humans, or human beings, are bipedal primates belonging to the mammalian species Homo sapiens (Latin for wise man or knowing man) under the family Hominidae (known as the great apes). ... Drawing of the structure of cork as it appeared under the microscope to Robert Hook from Micrographia which is the origin of the word cell. Cells in culture, stained for keratin (red) and DNA (green). ... For other uses, see Life (disambiguation), Lives (disambiguation) or Living (disambiguation), Living Things (disambiguation) Look up life, living in Wiktionary, the free dictionary. ... In biological cells that are electrically at rest, the cytosol possesses a uniform electric potential or voltage compared to the extracellular solution. ... Volume is a quantification of how much space a certain region occupies. ...

Function

In order to maintain the cell potential, cells must keep a low concentration of sodium ions and high levels of potassium ions within the cell (intracellular). Outside cells (extracellular), there are high concentrations of sodium and low concentrations of potassium, so diffusion occurs through ion channels in the plasma membrane. In order to keep the appropriate concentrations, the sodium-potassium pump pumps sodium out and potassium in through active transport. General Name, Symbol, Number sodium, Na, 11 Chemical series alkali metals Group, Period, Block 1, 3, s Appearance silvery white Atomic mass 22. ... General Name, Symbol, Number potassium, K, 19 Chemical series alkali metals Group, Period, Block 1, 4, s Appearance brownish white Atomic mass 39. ... In cell biology, molecular biology and related fields, the word intracellular means inside the cell. It is used in contrast to extracellular (outside the cell). ... In cell biology, molecular biology and related fields, the word extracellular means outside the cell. It is used in contrast to intracellular (inside the cell). ... This article or section does not cite its references or sources. ... Ion channels are pore-forming proteins that help to establish and control the small voltage gradient that exists across the plasma membrane of all living cells (see cell potential) by allowing the flow of ions down their electrochemical gradient. ... This article or section does not cite its references or sources. ...

The mechanism is:

• The pump, with bound ATP, binds 3 intracellular Na⁺ ions.
• ATP is hydrolyzed, leading to phosphorylation of the pump at a highly conserved aspartate residue and subsequent release of ADP.
• A conformational change in the pump exposes the Na⁺ ions to the outside. The phosphorylated form of the pump has a low affinity for sodium ions, so they are released.
• The pump binds 2 extracellular K⁺ ions, leading to the dephosphorylation of the pump.
• ATP binds, and the pump reorients to release potassium ions inside the cell so the pump is ready to go again.

Adenosine 5-triphosphate (ATP), discovered in 1929 by Karl Lohmann,[1] is a multifunctional nucleotide primarily known in biochemistry as the molecular currency of intracellular energy transfer. ... NA may refer to: Namibia (ISO country code) Narcotics Anonymous National Association, a banking term National Association of Professional Baseball Players North America North American Airlines, IATA airline designator One of several Northern Alliances Not Applicable (usually written N/a) Nucleic acid Numerical aperture - A specification in optical systems. ... ... Hydrolysis is a chemical process in which a molecule is cleaved into two parts by the addition of a molecule of water. ... Phosphorylation is the addition of a phosphate (PO4) group to a protein or a small molecule. ... Adenosine diphosphate, abbreviated ADP, is a nucleotide. ... General Name, Symbol, Number potassium, K, 19 Chemical series alkali metals Group, Period, Block 1, 4, s Appearance brownish white Atomic mass 39. ...

Physiology

As the plasma membrane is far less permeable to sodium than it is to potassium ions, an electric potential (negative intracellularly) is the eventual result.

The electrical and concentration gradient established by the sodium-potassium ATPase supports not only the cell resting potential but the action potentials of nerves and muscles. Export of sodium from the cell provides the driving force for several facilitated transporters, which import glucose, amino acids and other nutrients into the cell. Translocation of sodium from one side of an epithelium to the other side creates an osmotic gradient that drives the absorption of water. In biological cells that are electrically at rest, the cytosol possesses a uniform electric potential or voltage compared to the extracellular solution. ... A. A schematic view of an idealized action potential illustrates its various phases as the action potential passes a point on a cell membrane. ... Nerves (yellow) Nerves redirects here. ... It has been suggested that this article or section be merged into Muscular system. ... Glucose (Glc), a monosaccharide (or simple sugar), is one of the most important carbohydrates in biology. ... The general structure of an amino acid molecule, with the amine group on the left and the carboxyl group on the right. ...

Another important task of the Na⁺-K⁺ pump is to provide a Na⁺ gradient that is used by certain carrier processes. In the gut, for example, sodium is transported out of the resorbing cell on the blood side via the Na⁺-K⁺ pump, whereas, on the resorbing side, the Na⁺-Glucose symporter uses the created Na⁺ gradient as a source of energy to import both Na⁺ and Glucose, which is far more efficient than simple diffusion. Similar processes are located in the renal tubular system. For the Physics term GUT, please refer to Grand unification theory The gastrointestinal or digestive tract, also referred to as the GI tract or the alimentary canal or the gut, is the system of organs within multicellular animals which takes in food, digests it to extract energy and nutrients, and... A symporter, also known as a coporter, is an integral membrane protein that is involved in facilitated diffusion. ... Nephron of the kidney A nephron is the basic structural and functional unit of the kidney. ...

Pharmacology

The Na-K pump found in the membrane of heart cells is an important target of cardiac glycosides (for example digoxin and ouabain), drugs used to improve heart performance by increasing its force of contraction. Contraction of any muscle is dependent on a 100- to 10,000-times higher-than-resting intracellular Ca concentration, which, as soon as it is put back again on its normal level by a carrier enzyme in the plasma membrane, and a calcium pump in sarcoplasmic reticulum, muscle relaxes. Since this carrier enzyme (Na-Ca translocator) uses the Na gradient generated by the Na-K pump to remove Ca from the intracellular space, slowing down the Na-K pump results in a permanently-higher Ca level in the muscle, which will eventually lead to stronger contractions. Cardiac glycosides are drugs used in the treatment of congestive heart failure and cardiac arrhythmia. ... Digoxin is a cardiac glycoside extracted from the foxglove plant, digitalis. ... Ouabain is the familiar name of g-strophanthin, a poisonous cardiac glycoside. ... The heart and lungs, from an older edition of Grays Anatomy. ... Calcium plays a vital role in the anatomy, physiology and biochemistry of organisms and of the cell, particularly in signal transduction pathways. ... It has been suggested that this article or section be merged into Muscular system. ...

Discovery

Na⁺/K⁺-ATPase was discovered by Jens Christian Skou in 1957 while working as assistant professor at the Department of Physiology, University of Aarhus, Denmark. He published his work in Biochimica et Biophysica Acta (vol. 23, pp. 394-401) in a paper entitled "The Influence of some Cations on an Adenosine Triphosphatase from Peripheral Nerves" (PMID 13412736). Jens Christian Skou (born October 8, 1918) is a Danish chemist and Nobel laureate. ... 1957 (MCMLVII) was a common year starting on Tuesday of the Gregorian calendar. ... Aarhus Universitet or the University of Aarhus is a university based in Ã…rhus, Denmark. ...

In 1997, he received one-half of the Nobel Prize in Chemistry "for the first discovery of an ion-transporting enzyme, Na+, K+ -ATPase" ^[1]. This is a list of Nobel Prize laureates in Chemistry from 1901 to 2006. ...

Genes

• Alpha: ATP1A1, ATP1A2, ATP1A3, ATP1A4. #1 predominates in kidney. #2 is also known as "alpha(+)"
• Beta: ATP1B1, ATP1B2, ATP1B3, ATP1B4

External links

• Na+/K+-ATPase Pump (Flash Animations)
• MeSH Sodium,+Potassium+ATPase

Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. ...

See also

• V-ATPase
• active transport

V-ATPase schematic Vacuolar type H+-ATPase (V-ATPase) is a highly conserved evolutionarily ancient enzyme with remarkably diverse functions in eukaryotic organisms. ... This article or section does not cite its references or sources. ...

References

1. ^ [1]