Aging and calorie restriction modulate yeast redox state, oxidized protein removal, and the ubiquitin-proteasome system.
Free Radic Biol Med
; 51(3): 664-70, 2011 Aug 01.
Article
in En
| MEDLINE
| ID: mdl-21684330
ABSTRACT
The ubiquitin-proteasome system governs the half-life of most cellular proteins. Calorie restriction (CR) extends the maximum life span of a variety of species and prevents oxidized protein accumulation. We studied the effects of CR on the ubiquitin-proteasome system and protein turnover in aging Saccharomyces cerevisiae. CR increased chronological life span as well as proteasome activity compared to control cells. The levels of protein carbonyls, a marker of protein oxidation, and those of polyubiquitinated proteins were modulated by CR. Controls, but not CR cells, exhibited a significant increase in oxidized proteins. In keeping with decreased proteasome activity, polyubiquitinated proteins were increased in young control cells compared to time-matched CR cells, but were profoundly decreased in aged control cells despite decreased proteasomal activity. This finding is related to a decreased polyubiquitination ability due to the impairment of the ubiquitin-activating enzyme in aged control cells, probably related to a more oxidative microenvironment. CR preserves the ubiquitin-proteasome system activity. Overall, we found that aging and CR modulate many aspects of protein modification and turnover.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Saccharomyces cerevisiae
/
Aging
/
Oxidative Stress
/
Caloric Restriction
/
Proteasome Endopeptidase Complex
/
Unfolded Protein Response
Language:
En
Journal:
Free Radic Biol Med
Journal subject:
BIOQUIMICA
/
MEDICINA
Year:
2011
Document type:
Article
Affiliation country: