The DKK (Dickkopf) family of secreted proteins includes DKK-1 through -4, and a related protein, Soggy (DKK-11). Like DKK-1, DKK-2 can act as an antagonist of the Wnt signaling pathway, forming inhibitory complexes with Wnt co-receptor LRP6 and Kremen-2. However, when LRP6 is overexpressed direct binding of DKK-2 activates canonical Wnt signaling. DKK-2 is expressed in bone, eye and other mesenchymal tissues.