The renal type IIa Na/Pi cotransporter: Structure-function relationships

Abstract

The type IIa Na/P^sub i^ cotransporter mediates proximal tubular brush-border membrane secondary active phosphate (P^sub i^) flux. It is rate limiting in tubular P^sub i^ reabsorption and, thus, a final target in many physiological and pathophysiological situations of altered renal P^sub i^ handling (1-4). In the present short review, we will briefly summarize our current knowledge about the transport mechanism (cycle) as well as particular regions of the transporter protein ("molecular domains") that potentially determine transport characteristics.[PUBLICATION ABSTRACT]