Domains of axin and disheveled required for interaction and function in wnt signaling.

Department of Pathology, Department of OB/GYN, Department of Genetics and Development, Columbia University, 630 West 168 Street, New York, New York, 10032, USA.
Biochemical and Biophysical Research Communications (Impact Factor: 2.28). 11/2000; 276(3):1162-9. DOI: 10.1006/bbrc.2000.3607
Source: PubMed

ABSTRACT Disheveled blocks the degradation of beta-catenin in response to Wnt signal by interacting with the scaffolding protein, Axin. To define this interaction in detail we undertook a mutational and binding analysis of the murine Axin and Disheveled proteins. The DIX domain of Axin was found to be important for association with Disheveled and two other regions of Axin (between residues 1-168 and 600-810) were identified that can promote the association of Axin and Disheveled. We found that the DIX domain of Disheveled is critical for association with Axin in vivo and for Disheveled activity. The Disheveled DIX domain controlled the ability of Disheveled to induce the accumulation of cytosolic beta-catenin whereas the PDZ domain was not essential to this function.

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