Structural features and nucleotide-binding capability of the C subunit are integral to the regulation of the eukaryotic V1Vo ATPases.
V-ATPases (vacuolar ATPases) are responsible for acidification of intracellular compartments and, in certain cases, proton transport across the plasma membrane of eukaryotic cells. They are composed of a catalytic V1 sector, in which ATP hydrolysis takes place, and the Vo sector, which functions in proton conduction. The best established mechanism for regulating the V-ATPase activity in vivo involves reversible dissociation of the V1 and Vo domains, in which subunit C is intimately involved. In the last year, impressive progress has been made in elucidating the structure of the C subunit and its arrangement inside the V-ATPase. Nucleotide occupancy by subunit C, followed by conformational changes of this subunit has shed light on the mechanism of V-ATPase regulation.
Grüber
G
G
Universität des Saarlandes, Fachrichtung 2.5-Biophysik, Universitätsbau 76, D-66421 Homburg, Germany. ggrueber@ntu.edu.sg
D000255:Adenosine Triphosphate / Q000378:metabolism; D008958:Models, Molecular; D020836:Protein Structure, Quaternary; D021122:Protein Subunits / Q000737:chemistry / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism*; D025262:Vacuolar Proton-Translocating ATPases / Q000737:chemistry* / Q000378:metabolism*
D021122:Protein Subunits; D029701:Saccharomyces cerevisiae Proteins; C447616:VMA5 protein, S cerevisiae; D000255:Adenosine Triphosphate; D025262:Vacuolar Proton-Translocating ATPases