Correlating charge movements with local conformational changes of a Na(+)-coupled cotransporter.

ABSTRACT: To gain insight into the steady-state and dynamic characteristics of structural rearrangements of an electrogenic secondary-active cotransporter during its transport cycle, two measures of conformational change (pre-steady-state current relaxations and intensity of fluorescence emitted from reporter fluorophores) were investigated as a function of membrane potential and external substrate. Cysteines were substituted at three believed-new sites in the type IIb Na(+)-coupled inorganic phosphate cotransporter (SLC34A2 flounder isoform) that were predicted to be involved in conformational changes. Labeling at one site resulted in substantial suppression of transport activity, whereas for the other sites, function remained comparable to the wild-type. For these mutants, the properties of the pr

SUBMITTER: Patti M 

PROVIDER: S-EPMC4008805 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature