Wnt signaling pathway belongs among ancient and evolutionarily conserved pathways guiding cell proliferation and cell-cell communication in tissues. The dysfunction of Wnt pathway is connected to development defects, inherited diseases, and cancer [1]. Dishevelled (DVL) protein plays a pivotal role in the Wnt pathway as a key signaling hub [2], however, the regulation of DVL function still remains largely unknown [3]. Here, we investigated the effects of posttranslational modifications on DLVs PDZ domain, a key domain common to all Wnt signaling pathways [1]. In particular, we focused on recently determined phosphorylation sites in the third isoform of human DVL protein (hDVL3) using molecular dynamics simulations. We discovered that the four biologically relevant phosphorylations can be split into two groups with a distinct mode of action. The first group situated on the β2 strand caused strong electrostatic interaction across the canonical binding cleft, effectively closing it. While phosphorylations in the second group induced stabilization of the long β2-β3 loop, a typical secondary binding site [4]. We also investigated the behavior of phosphomimetics, a frequently used mimic of the phosphorylated residue by their mutation to either glutamic or aspartic acid, which effects were similar but weaker compared to phosphorylated residues. Our findings provide a molecular understanding of how phosphorylation influence PDZ structure in DVL protein and may be applied to other PDZ domains which are frequently occurring protein-protein recognition motif [5].