Upon stimulation with WNT ligand, AXIN and GSK3beta are recruited to the plasma membrane through interaction with DVL (Tamai et al, 2004; Mao et al, 2001; reviewed in He et al, 2004). Polymerization of membrane-associated DVL and GSK3beta- and CSNK1-mediated phosphorylation of LRP5/6 establish a feed-forward mechanism for enhanced membrane recruitment of AXIN upon WNT signaling (Tamai et al, 2004; Cong et al, 2004; Zeng et al, 2005; Bilic et al, 2007). In Xenopus oocytes, but not necessarily all sytems, AXIN is present in limiting concentrations and is considered rate limiting for the assembly of the destruction complex (Lee et al, 2003; Benchabane et al, 2008; Tan et al, 2012; reviewed in MacDonald et al, 2009). The recruitment of AXIN away from the destruction complex upon WNT stimulation effectively destabilizes the destruction complex and contributes to the accumulation of free beta-catenin (Kikuchi, 1999; Lee et al, 2003). AXIN association with the destruction complex is also regulated by phosphorylation. In the active destruction complex, AXIN is phosphorylated by GSK3beta; dephosphorylation by protein phosphatase 1 (PP1) or protein phosphatase 2A (PP2A) destabilizes the interaction of AXIN with the other components of the destruction complex and promotes its disassembly (Luo et al, 2007; Willert et al, 1999; Jho et al, 1999). Free AXIN is also subject to degradation by the 26S proteasome in a manner that depends on the poly-ADP-ribosylating enzymes tankyrase 1 and 2 (Huang et al, 2009).