Intranuclear degradation of polyglutamine aggregates by the ubiquitin-proteasome system.

ABSTRACT: Huntington disease and its related autosomal-dominant polyglutamine (pQ) neurodegenerative diseases are characterized by intraneuronal accumulation of protein aggregates. Studies on protein aggregates have revealed the importance of the ubiquitin-proteasome system as the front line of protein quality control (PQC) machinery against aberrant proteins. Recently, we have shown that the autophagy-lysosomal system is also involved in cytoplasmic aggregate degradation, but the nucleus lacked this activity. Consequently, the nucleus relies entirely on the ubiquitin-proteasome system for PQC. According to previous studies, nuclear aggregates possess a higher cellular toxicity than do their cytoplasmic counterparts, however degradation kinetics of nuclear aggregates have been poorly understood. Her

SUBMITTER: Iwata A 

PROVIDER: S-EPMC2665101 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature