title: The plasma membrane calcium pump: new ways to look at an old enzyme.
abstract: The three-dimensional structure of the PMCA pump has not been solved, but its basic mechanistic properties are known to repeat those of the other Ca(2+) pumps. However, the pump also has unique properties. They concern essentially its numerous regulatory mechanisms, the most important of which is the autoinhibition by its C-terminal tail. Other regulatory mechanisms involve protein kinases and the phospholipids of the membrane in which the pump is embedded. Permanent activation of the pump, e.g. by calmodulin, is physiologically as harmful to cells as its absence. The concept is now emerging that the global control of cell Ca(2+) may not be the main function of the pump; in some cell types, it could even be irrelevant. The main pump role would be the regulation of Ca(2+) in cell microdomains in which the pump co-segregates with partners that modulate the Ca(2+) message and transduce it to important cell functions.
authors.affiliation: Department of Biomedical Sciences, University of Padova, 35121 Padova.
authors.forename: Raffaele
authors.initials: R
authors.lastname: Lopreiato
authors.affiliation: Venetian Institute of Molecular Medicine, University of Padova, 35129 Padova, Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: Giacomello
authors.affiliation: Venetian Institute of Molecular Medicine, University of Padova, 35129 Padova, Italy. Electronic address: ernesto.carafoli@unipd.it.
authors.forename: Ernesto
authors.initials: E
authors.lastname: Carafoli
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D017360:Arabidopsis / Q000201:enzymology; D002118:Calcium / Q000737:chemistry*; D020013:Calcium Signaling; D000252:Calcium-Transporting ATPases / Q000737:chemistry; D002147:Calmodulin / Q000737:chemistry; D002462:Cell Membrane / Q000201:enzymology*; D006801:Humans; D021962:Membrane Microdomains / Q000201:enzymology; D010743:Phospholipids / Q000737:chemistry; D053499:Plasma Membrane Calcium-Transporting ATPases / Q000737:chemistry*; D011485:Protein Binding; D020033:Protein Isoforms / Q000737:chemistry; D017434:Protein Structure, Tertiary
chemical_list: D002147:Calmodulin; D010743:Phospholipids; D020033:Protein Isoforms; D053499:Plasma Membrane Calcium-Transporting ATPases; D000252:Calcium-Transporting ATPases; D002118:Calcium
keywords: Calcium ATPase; Calcium Signaling; Calcium Transport; Calmodulin; Phospholipid