Rat alpha 2u-Globulin (AUG), also known as major urinary protein, belongs to the lipocalin protein family. Under complex hormonal control, alpha 2u-globulin is a low molecular weight protein expressed in a tissue-, age-, and sex-specific fashion. Circulating alpha 2u-globulin is expressed by the liver. It is removed from the plasma by the kidney and excreted.
Rodent studies have employed alpha 2u-globulin nephropathy as an experimental model for the development of kidney tumors. Induction of alpha 2u-globulin nephropathy alters the number, size and shape of hyaline droplets in the proximal tubules. Intra-cellular accumulation of alpha 2u-globulin induces cell death and necrosis of tubular epithelial cells.