Send to:

Choose Destination
See comment in PubMed Commons below
Mol Cell Biol. 2002 Sep;22(17):6100-10.

Regulation of Wnt/LRP signaling by distinct domains of Dickkopf proteins.

Author information

  • 1Department of Microbiology and Molecular Genetics, Harvard Medical School. Molecular Medicine Unit, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA.


Dickkopfs (Dkks) are secreted developmental regulators composed of two cysteine-rich domains. We report that the effects of Dkks depend on molecular context. Although Wnt8 signaling is inhibited by both Dkk1 and Dkk2 in Xenopus embryos, the same pathway is activated upon interaction of Dkk2 with the Wnt coreceptor LRP6. Analysis of individual Dkk domains and chimeric Dkks shows that the carboxy-terminal domains of both Dkks associate with LRP6 and are necessary and sufficient for Wnt8 inhibition, whereas the amino-terminal domain of Dkk1 plays an inhibitory role in Dkk-LRP interactions. Our study illustrates how an inhibitor of a pathway may be converted into an activator and is the first study to suggest a molecular mechanism for how a ligand other than Wnt can positively regulate beta-catenin signaling.

[PubMed - indexed for MEDLINE]
Free PMC Article

Publication Types, MeSH Terms, Substances

PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk