Abstract: Objective To characterize the binding property of GIPC2 PDZ domain by validation screening of PDZ ligand library, and identification of the interaction proteins of GIPC2. Methods 1) The binding properties of GIPC2 PDZ domain were characterized by validation screening of the PDZ ligand library with yeast two-hybrid approach, 2) According to the subcellular localization, involvement in the development of tumor, combined with the PDZ binding properties, the candidate GIPC2 binding ligands were predicted. 3) The candidate ligands were validated with GIPC2 PDZ domain and GIPC2. Results 1) The binding property of GIPC2 PDZ domain is that the last four amino acid residues of C termini are –X-S/T-X-V/L/I and belonging a type I PDZ ligand. 2) Integrated the biological characterization of GIPC2 and the PDZ binding properties, 47 candidate GIPC2 binding ligands were predicted. 3) 10 of 47 candidate ligands were validated to interact with GIPC2 PDZ domain and GIPC2 using yeast two hybrid. Conclusions Ten interaction proteins of GIPC2 were identified.

Key words: GIPC2 , PDZ domain , protein interaction , PDZ Ligand library , yeast two hybrid