title: Active phosphate ion transport in plasma membrane vesicles isolated from mouse fibroblasts.
abstract: Inorganic phosphate accumulated 8-fold in plasma membrane vesicles derived from simian virus 40-transformed 3T3 mouse fibroblasts when a NaCl gradient (external greater than internal) was artificially imposed across the membrane. Preincubation with Na+ or addition of monensin markedly reduced phosphate accumulation. Na+-stimulated phosphate transport was not affected by addition of either dicarboxylic acids, antimycin A, or ouabain and persisted after addition of proton ionophores. The coupling of phosphate transport to Na+ gradients was pH-dependent, with maximal stimulation by Na+ below pH 7. These findings suggest that monovalent phosphate anion moves across the plasma membrane in co-transport with sodium ion.
mesh_terms: D001149:Arsenates / Q000494:pharmacology; D001693:Biological Transport, Active / Q000187:drug effects; D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism*; D002472:Cell Transformation, Viral; D005347:Fibroblasts / Q000378:metabolism; D007476:Ionophores / Q000494:pharmacology; D007700:Kinetics; D010710:Phosphates / Q000378:metabolism*; D013539:Simian virus 40; D012964:Sodium / Q000494:pharmacology
chemical_list: D001149:Arsenates; D007476:Ionophores; D010710:Phosphates; D012964:Sodium