DKK3 is a protein that is a member of the dickkopf family. The secreted protein contains two cysteine rich regions and is involved in embryonic development through its interactions with the Wnt signaling pathway. The expression of this gene is decreased in a variety of cancer cell lines and it may function as a tumor suppressor gene. Alternative splicing results in multiple transcript variants encoding the same protein.DKK3 has 4 potential N-glycosylation sites and possesses an extended N-terminal domain preceding the first cys domain as well as an extended C-terminal region following the second cys domain. All DKKs have several potential sites for cleavage by furin-type proteases. Northern blot analysis revealed wide expression of a 2.5-kb DKK3 transcript, with highest expression in heart, brain, and spinal cord.