The PDZ-binding motif of MCC is phosphorylated at position − 1 and controls lamellipodia formation in colon epithelial cells

► First functional characterization of − 1 phosphorylation of the PDZ binding motif. ► Mutation of the S828 phosphosite of MCC disrupts lamellipodia formation. ► Phosphorylation of MCC-S828 is predicted to increase MCC interaction with Scrib. ► MCC also interacts with the non-muscle motor protein Myosin-IIB. ► Mutation of MCC-S828 traps Myosin-IIB in the membrane cortex.