K83 site affects PICK1 PDZ binding ability / 浙江大学学报·医学版

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the role of 83 site in interaction of GluR2 C-terminal and PICK1 PDZ domain.</p><p><b>METHODS</b>Docking structure of PICK1 PDZ domain with GluR2 C terminal PDZ binding motif was built with computer software. After K83 site was substituted by other amino acid, the structure and binding energy were recalculated; meanwhile, site specific mutants were constructed using wild type full length cDNA as template. Mutants were co-transfected with GluR2 into HEK293T cells. After staining, the distribution of PICK1 and GluR2 were observed under confocal microscope.</p><p><b>RESULTS</b>Wild type PICK1 and GluR2 formed many co-clusters in HEK293T cells as reported by other research groups; but different K83 mutant had different distribution in HEK293T cells.</p><p><b>CONCLUSION</b>The K83 site in PDZ domain of PICK1 is important for the interaction between PICK1 and GluR2. Altering lysine will probably change the hydrophobic interactions, the hydrogen bonds or the electrostatic interactions formed between PICK1 PDZ domain and GluR2 C terminal; accordingly, that will change the binding capacity between PICK1 and GluR2 in varying degrees.</p>