FIG 10.

GATA2 regulates the Aqp2 gene expression in the CD and contributes to maintenance of the body water homeostasis. (A) Schematic diagram of nephron. Aqp2-mediated water absorption takes place in the CD. (B) GATA2 is expressed in all the CD cells, including principal cells. (C) In the principal cells of CD, GATA2 directly activates Aqp2 gene expression and maintains the normal water reabsorption mechanism from urine. Upon Avp stimulus, Avpr2 signaling induces PKA (protein kinase A)-mediated phosphorylation of Aqp2 and CREB. Phosphorylated Aqp2 translocates to the luminal side of principal cells. Phosphorylated and activated CREB participates in transactivation of Aqp2 gene.