 Soluble inositol-(1,4,5)-trisphosphate triggers calcium to be released from the endoplasmic reticulum.This sudden increase in cytoplasmic calcium activates Ca2+/calmodulin-dependent protein kinase (CaMKII).Activated CaMKII destabilizes β-catenin via a poorly characterized mechanism, but which likely involves β-catenin phosphorylation by CaMKII.