<p>An evidence describes the source of an annotation, e.g. an experiment that has been published in the scientific literature, an orthologous protein, a record from another database, etc.</p>
Protein involved in the movement of sodium ions across energy-transducing cell membranes. Primary active sodium transport is coupled to an energy-yielding chemical reaction such as ATP hydrolysis. Secondary active transport utilizes the voltage and ion gradients produced by the primary transport to drive the cotransport of other ions or molecules. These may be transported in the same (symport) or opposite (antiport) direction.