Parkinson’s disease(PD) is a common neurodegenerative disorder whose primary pathology features are the degeneration of dopaminergic neurons in the substantia nigra pars compacta(SNc) and the presence of eosinophilic inclusions called Lewy body in the cytoplasm of the remained neurons.Growing evidence suggests that dysfunction of the ubiquitin-proteasome system(UPS) is involved in the etiopathogenesis of PD.In order to investigate the pathogenetic mechanism of ubiquitin-proteasome dysfunction in PD,2D-differential gel electrophoresis (2D-DIGE) and MALDI-TOF Pro MS were used to determine the proteins,which were differentially expressed,in PC12 cells that had undergone a synthetic proteasomal inhibitor PSI(10μmol/L) treatment for 24 h.Forty-six protein spots were differentially expressed in response to PSI administration,of which 34 were increased and 12 decreased. Six of these were identified as molecular charperones:endoplasmin precursor(GRP94),heat shock protein 105(HSP105),HSC-70-psl,glucose ruglated protein 75(GRP75),glucose ruglated protein 58(GRP58) and heat shock 27000 protein 1(HSP27).The results suggest that the molecular chaperones play an important role in the PD model induced by proteasomal inhibitor. Parkinson’s disease (PD) is a common neurodegenerative disorder whose primary pathology features are the degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNc) and the presence of eosinophilic inclusions called Lewy body in the cytoplasm of the remained neurons. Growth evidence suggests that dysfunction of the ubiquitin-proteasome system (UPS) is involved in the etiopathogenesis of PD. order to investigate the pathogenetic mechanism of ubiquitin-proteasome dysfunction in PD, 2D-differential gel electrophoresis (2D-DIGE) and MALDI-TOF Pro MS were used to determine the proteins, which were differentially expressed in PC12 cells that had undergone a synthetic proteasomal inhibitor PSI (10 μmol / L) treatment for 24 h. Forty-six protein spots were differentially expressed in response to PSI administration, of which 34 were increased and 12 decreased. Six of these were identified as molecular charperones: endoplasmin precursor (GRP94), heat shock protein 105 (HSP105), HSC-70-ps l, glucose ruglated protein 75 (GRP75), glucose rugged protein 58 (GRP58) and heat shock 27000 protein 1 (HSP27). The results suggest that the molecular chaperones play an important role in the PD model induced by proteasomal inhibitor.