beta-Catenin Blocking Peptide

β-catenin is a key downstream effector in the Wnt signaling pathway (1). It is implicated in two major biological processes in vertebrates: early embryonic development (2) and tumorigenesis (3). CK1 phosphorylates β-catenin at Ser45. This phosphorylation event primes β-catenin for subsequent phosphorylation by GSK-3β (4-6). GSK-3β destabilizes β-catenin by phosphorylating it at Ser33, Ser37, and Thr41 (7). Mutations at these sites result in the stabilization of β-catenin protein levels and have been found in many tumor cell lines (8). 1.Cadigan, K.M. and Nusse, R. (1997) Genes Dev 11, 3286-3305. 2.Wodarz, A. and Nusse, R. (1998) Annu Rev Cell Dev Biol 14, 59-88. 3.Polakis, P. (1999) Curr Opin Genet Dev 9, 15-21. 4.Amit, S. et al. (2002) Genes Dev 16, 1066-76. 5.Liu, C. et al. (2002) Cell 108, 837-47. 6.Yanagawa, S. et al. (2002) EMBO J 21, 1733-42. 7.Yost, C. et al. (1996) Genes Dev 10, 1443-54. 8.Morin, P.J. et al. (1997) Science 275, 1787-90.