Calpain regulates N-terminal interaction of GSK-3β with 14-3-3ζ, p53 and PKB but not with axin

► Calpain produces a truncation of GSK3β that removes the N-terminal inhibitory domain. ► GST-pull-down protocol is used to analyze the effect of that truncation on protein-protein interaction. ► N-terminal end is necessary for 14-3-3ζ, p53 and PKB interaction, but not for axin.