Like GLI3, GLI2 has putative GSK3 sites that contribute to the proteasome-dependent degradation of the protein in the absence of Hh signal. Deletion of the GSK3 phosphorylation sites abrogates the interaction with beta-TrCP, stabilizes GLI2 protein and increases the expression of a GLI-dependent reporter, consistent with a role for GSK3 in promoting GLI2 degradation (Pan et al, 2006).
