Quality control of the proteins associated with neurodegenerative diseases

Most neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, Huntington's disease and other polyglutamine diseases are associated with degeneration and death of specific neuronal populations due to misfolding or aggregation of certain proteins. These aggregates often contain ubiquitin that is the signal for proteolysis by the ubiquitin-proteasome system, and chaperone proteins that are involved in the assistance of protein folding. Here we review the role of protein quality control systems in the pathogenesis of neurodegenerative diseases, and aim to learn more from the cooperation between molecular chaperones and ubiquitin-proteasome system responding to cellular protein aggregates, in order to find molecular targets for therapeutic intervention.