Transcription factor that may have a role in kidney cell differentiation. Interacts with ELGN3; the interaction targets PAX2 for destruction. Interacts with TLE4. Kidney and nephrogenic rests. Expressed in the developing embryo excretory and central nervous systems. In the developing excretory system; expressed in the pronephric tubules and extending nephric duct beginning at day 9 gestation. At 10 dpc, detected in the nephric cord, Wolffian duct and also individual pronephric tubules. At 11 dpc, expressed in the branched ureter and the mesenchymal condensations, at 12 dpc, expression seen in the collecting ducts and condensed mesenchymal cells. At 14-17 dpc, expressed in the perimeter of the growing kidney but expression declines in the more developed glomerular crevices, and at later developmental stages expression in the kidney declines. In the developing CNS; initially expressed in the ventricular zone in two compartments of cells on either side of the sulcus limitans and along the entire rhombencephalon and spinal cord, later is restricted to progeny cells that have migrated to specific regions of the intermediate zone. In the eye, expression is restricted to the ventral half of the optic cup and stalk and later to the optic disk and nerve. In the ear, expression is restricted to regions of the otic vesicle that form neuronal components. Defects in Pax2 are a cause of developmental defects of the kidney, brain, ear and eye.