Phosphate (Pi) plays important roles in growth, development, bone mineralization, energy metabolism, nucleic acid synthesis, cell signaling, and acid–base regulation. The rate of intestinal absorption of Pi is a major determinant of Pi homeostasis. The type IIb sodium-dependent Pi cotransporter (NaPi-IIb) is responsible for intestinal Pi absorption. Many physiological factors regulate the rate of Pi absorption via modulating the expression of NaPi-IIb in the intestine. In this review, we summarize the role of these factors in the regulation of NaPi-IIb expression in the intestine.
