Chordin-like 2 (CHL2, CHRDL2, or BNF-1), is a secreted glycoprotein that functions as a BMP antagonist. It is expressed in chondrocytes in developing joint cartilage, osteoblasts, myotubes, brain, some carcinomas, and the genitourinary system (e.g. uterus, prostate, testis, bladder). CHL2 binds to multiple TGF-beta superfamily proteins including BMP-2, -4, -5, -6, -7, GDF-5, Activin A, and TSG. It prevents the binding of BMPs to type 1 and type 2 receptors as well as BMP-induced cellular responses. CHL2 reduces the rate of matrix deposition by mesenchymal cells, acting as a negative regulator of cartilage formation.