Dapper, a Dishevelled-associated antagonist of beta-catenin and JNK signaling, is required for notochord formationCheyette, B.N.R., Waxman, J.S., Miller, J.R., Takemaru, K.-I., Sheldahl, L.C., Khlebtsova, N., Fox, E.P., Earnest, T., Moon, R.T.
(2002) Dev Cell 2: 449-461
- PubMed: 11970895
- DOI: https://doi.org/10.1016/s1534-5807(02)00140-5
- Primary Citation of Related Structures:
- PubMed Abstract:
Dapper was isolated in a screen for proteins interacting with Dishevelled, a key factor in Wnt signaling. Dapper and Dishevelled colocalize intracellularly and form a complex with Axin, GSK-3, CKI, and beta-catenin. Overexpression of Dapper increases Axin and GSK-3 in this complex, resulting in decreased soluble beta-catenin and decreased activation of beta-catenin-responsive genes. Dapper also inhibits activation by Dishevelled of c-Jun N-terminal kinase (JNK), a component of beta-catenin-independent Frizzled signaling. Inhibition of Dapper activates both beta-catenin-responsive genes and an AP1-responsive promoter, demonstrating that Dapper is a general Dishevelled antagonist. Depletion of maternal Dapper RNA from Xenopus embryos results in loss of notochord and head structures, demonstrating that Dapper is required for normal vertebrate development.
Howard Hughes Medical Institute, Department of Pharmacology and Center for Developmental Biology, University of Washington School of Medicine, Seattle, WA 98195, USA.