Anticipating antiport in P-type ATPases.
Cation-transporting P-type ATPases show a high degree of structural and functional homology. Nevertheless, for many members of this large family, the molecular mechanism of transport is unclear; namely, whether transport is electrogenic or not and if countertransport is involved remains to be established. In a few well-studied cases such as the Na(+)-K(+)-ATPase, plasma membrane Ca(2+) ATPase (PMCA) and sarcoplasmic reticulum Ca(2+) ATPase (SERCA) countertransport has been clearly demonstrated. New data based on the crystal structure of SERCA now strongly indicate that countertransport could be mandatory for all P-type ATPases. This concept should be verified for other known and for all newly characterized P-type ATPases.
Niggli
Verena
V
Institute of Pathology, University of Bern, Murtenstrasse 31, Bern, Switzerland. verena.niggli@pathology.unibe.ch
Sigel
Erwin
E
D000818:Animals; D001692:Biological Transport; D027682:Cation Transport Proteins / Q000378:metabolism; D018360:Crystallography, X-Ray; D004594:Electrophysiology; D006801:Humans; D017136:Ion Transport; D008954:Models, Biological; D010940:Plant Proteins / Q000378:metabolism; D053499:Plasma Membrane Calcium-Transporting ATPases / Q000378:metabolism*; D021381:Protein Transport; D012519:Sarcoplasmic Reticulum / Q000378:metabolism; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases / Q000378:metabolism
D027682:Cation Transport Proteins; D010940:Plant Proteins; D053499:Plasma Membrane Calcium-Transporting ATPases; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases