Angiopoietin-like protein 2 and kidney fibrosis: lessons from knockout mice.

The angiopoietin-like protein (ANGPTL) family is homologous to angiopoietins but does not bind to the Tie2 receptor. The function of ANGPTLs has been elucidated largely in the context of angiogenesis and lipid metabolism. Morinaga et al. demonstrated that genetic depletion of Angptl2 confers amelioration of the mouse kidney fibrosis induced by a unilateral ureteral obstruction, implicating that ANGPTL2, predominantly in the renal tubular compartments, activates the transforming growth factor-β signaling and vice versa through miR-221.