Molecular cloning and characterization of a novel form of the human vacuolar H+-ATPase e-subunit: an essential proton pump component.
Article Details
- CitationCopy to clipboard
Blake-Palmer KG, Su Y, Smith AN, Karet FE
Molecular cloning and characterization of a novel form of the human vacuolar H+-ATPase e-subunit: an essential proton pump component.
Gene. 2007 May 15;393(1-2):94-100. doi: 10.1016/j.gene.2007.01.020. Epub 2007 Feb 7.
- PubMed ID
- 17350184 [ View in PubMed]
- Abstract
Several of the 13 subunits comprising mammalian H(+)-ATPases have multiple alternative forms, encoded by separate genes and with differing tissue expression patterns. These may play an important role in the intracellular localization and activity of H(+)-ATPases. Here we report the cloning of a previously uncharacterized human gene, ATP6V0E2, encoding a novel H(+)-ATPase e-subunit designated e2. We demonstrate that in contrast to the ubiquitously expressed gene encoding the e1 subunit (previously called e), this novel gene is expressed in a more restricted tissue distribution, particularly kidney and brain. We show by complementation studies in a yeast strain deficient for the ortholog of this subunit, that either form of the e-subunit is essential for proper proton pump function. The identification of this novel form of the e-subunit lends further support to the hypothesis that subunit differences may play a key role in the structure, site and function of H(+)-ATPases within the cell.