Comparative Phosphoproteomic Analysis Of Autosomal Dominant Polycystic Kidney Disease

Objective: To explore the pathogenessis of ADPKD and look for the therapy target by analyzing the differential phosphoprotein of ADPKD in a large scale. Methods: we collected the ADPKD kidney tissues and normal kidney tissues samples , extracted the total proteins and enriched the phosphoproteins. The proteome samples were separated by 2-DE. Differential protein spots were excised and digested into peptides. They were separated by RP-HPLC and identified by ESI-MS /MS. Data were then searched with SEQUEST software. Several differential phosphoproteins were also testified by immunoprecipitation and western blot. A differential phosphoprotein was chosen to investigate its impact on the cells by being up or down regulated its expression. Results: we successfully identified 38 differential phosphoproteins including cell signaling proteins, cytoskeletal proteins, and energy metabolism regulators. Three differential phosphorylated proteins from all the identified proteins were chosen to be testified by immunoprecipitation and western blot. The results showed the relative abundance ratios nearly identical to the ratios determined by MS/MS. Annexinâ…¡which was up regulated in ADPKD kidney tissues was chosen for the further studied. The results showed annexinâ…¡and p-tyr annexinâ…¡might take part in the role of promoting proliferation in ADPKD . The expressions of total annexinâ…¡and p-tyr annexinâ…¡were both reduced by RNA interfere which could inhibit the cell proliferation and promote the apoptosis.