Electrogenic sodium bicarbonate cotransporter 1 is a membrane transport protein that in humans is encoded by the SLC4A4 gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

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NBCe1-A aka kNBC1 (mainly expressed in the kidney)

NBCe1-B aka pNBC1 (expressed in the pancreas and elsewhere)

NBCe1-C (expressed in the brain)
The renal SLC4A4 gene product NBCe1-A is specifically expressed in the basolateral membranes of proximal tubule epithelia.
NBCe1 may participate in regulation of brain extracellular space pH

PH

In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...

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