Degradation of an intramitochondrial protein by the cytosolic proteasome.
J Cell Sci
; 123(Pt 4): 578-85, 2010 Feb 15.
Article
in En
| MEDLINE
| ID: mdl-20103532
ABSTRACT
Mitochondrial uncoupling protein 2 (UCP2) is implicated in a wide range of pathophysiological processes, including immunity and diabetes mellitus, but its rapid degradation remains uncharacterized. Using pharmacological proteasome inhibitors, immunoprecipitation, dominant negative ubiquitin mutants, [corrected] cellular fractionation and siRNA techniques, we demonstrate the involvement of the ubiquitin-proteasome system in the rapid degradation of UCP2. Importantly, we resolve the issue of whether intramitochondrial proteins can be degraded by the cytosolic proteasome by reconstituting a cell-free system that shows rapid proteasome-inhibitor-sensitive UCP2 degradation in isolated, energised mitochondria presented with an ATP regenerating system, ubiquitin and 26S proteasome fractions. These observations provide the first demonstration that a mitochondrial inner membrane protein is degraded by the cytosolic ubiquitin-proteasome system.
Full text:
1
Database:
MEDLINE
Main subject:
Mitochondrial Proteins
/
Proteasome Endopeptidase Complex
/
Ion Channels
Type of study:
Prognostic_studies
Limits:
Animals
Language:
En
Year:
2010
Type:
Article