All share a similar catalytic mechanism, by which a conserved cysteine residue forms a covalent intermediate with the phosphate group to be eliminated.
The serine side chain and an additional conserved aspartate play a central role in the elimination of the Cys-linked intermediate, thus completing their enzymatic cycle.
The four mammalian Cdc14 proteins (named KAP, Cdc14A, Cdc14B and PTP9Q22) play a crucial role in cell cycle regulation by dephosphorylating cyclin-dependent kinases, most importantly CDK2.
Though structurally related to other DUSPs, these are not strictly phosphorotein-phosphatases, since their most important substrates are phosphorylated inositol lipids.
The surface of this substrate-binding domain mimics the D-motifs found in intrinsically disordered substrates of MAPKs.