Dickkopf Related Protein 1 (DKK1)

Dickkopf-related protein 1 is a protein that is a member of the dickkopf family. It is a secreted protein with two cysteine rich regions and is involved in embryonic development through its inhibition of the WNT signaling pathway. Elevated levels of DKK1 in bone marrow plasma and peripheral blood is associated with the presence of osteolytic bone lesions in patients with multiple myeloma. Sequence analysis predicted that the 266-amino acid DKK1 protein contains a 31-amino acid N-terminal signal peptide, 2 clusters of cysteine residues, and a potential C-terminal N-glycosylation site. SDS-PAGE and Western blot analysis demonstrated that DKK1 is expressed as a 35-kD doublet protein, which is larger than the deduced molecular mass of 26 kD.