Download MendeleyCrystal structure of a beta-catenin/Axin complex suggests a mechanism for the {beta}-catenin destruction complex
Xing, Y., Clements, W.K., Kimelman, D., Xu, W.(2003) Genes Dev 17: 2753-2764
- PubMed: 14600025
- DOI: https://doi.org/10.1101/gad.1142603
- Primary Citation of Related Structures:
1QZ7 - PubMed Abstract:
The "beta-catenin destruction complex" is central to canonical Wnt/beta-catenin signaling. The scaffolding protein Axin and the tumor suppressor adenomatous polyposis coli protein (APC) are critical components of this complex, required for rapid beta-catenin turnover. We determined the crystal structure of a complex between beta-catenin and the beta-catenin-binding domain of Axin (Axin-CBD). The Axin-CBD forms a helix that occupies the groove formed by the third and fourth armadillo repeats of beta-catenin and thus precludes the simultaneous binding of other beta-catenin partners in this region. Our biochemical studies demonstrate that, when phosphorylated, the 20-amino acid repeat region of APC competes with Axin for binding to beta-catenin. We propose that a key function of APC in the beta-catenin destruction complex is to remove phosphorylated beta-catenin product from the active site.
Organizational Affiliation:
Department of Biological Structure, University of Washington, Seattle, Washington 98195, USA.
