GREM2 is a member of the BMP (bone morphogenic protein) antagonist family. Like BMPs, BMP antagonists contain cystine knots and typically form homo- and heterodimers. The CAN (cerberus and dan) subfamily of BMP antagonists, to which this protein belongs, is characterized by a C-terminal cystine knot with an eight-membered ring. The antagonistic effect of the secreted glycosylated protein is likely due to its direct binding to BMP proteins. As an antagonist of BMP, this protein may play a role in regulating organogenesis, body patterning, and tissue differentiation. Recombinant human GREM2 protein, fused to His-tag at N-terminus, was expressed in E.coli.