Calcium release in response to WNT5A has been shown to activate calcium/calmodulin-dependent protein kinase 2 (CAMK2) (Kuhl et al, 2000; Ishitani et al, 2003a). Human cells have 4 genes encoding CAMK: alpha, beta, delta and gamma. Alpha and beta isoforms are expressed in neuronal tissue while delta and gamma isoforms have broad tissue distribution. The enzyme exists as either a homo- or hetero- dodecamer of ill-defined stoichiometry. In the inactive state, the autoinhibitory loop of CAMK2 blocks the active site. Upon binding of Ca2+/calmodulin, the autoinhibitory loop is displaced, allowing subsequent autophosphorylation at T286 in CAMK2 alpha and activation of the kinase (reviewed in Stratton et al, 2013).
WNT-dependent activation of CAMK2 is inhibited by an interaction between oncogenic KRAS4B and calmodulin. This promotes tumorigenesis by relieving the suppression of beta-catenin dependent signaling mediated by the non-canonical WNT signaling pathway (Wang et al, 2015).