Orlandi I, et al. (2010) Sir2-dependent asymmetric segregation of damaged proteins in ubp10 null mutants is independent of genomic silencing. Biochim Biophys Acta 1803(5):630-638
Abstract: Carbonylation of proteins is irreversible oxidative damage that increases during both chronological and replicative yeast aging. In the latter, a spatial protein quality control system that relies on Sir2 is responsible for the asymmetrical damage segregation in the mother cells. Proper localization of Sir2 on chromatin depends on the deubiquitinating enzyme Ubp10, whose loss of function deeply affects the recombination and gene-silencing activities specific to Sir2. Here, we have analyzed the effects of SIR2 and UBP10 inactivations on carbonylated proteins patterns obtained in two aging models such as stationary phase cells and size-selected old mother ones. In line with the endogenous situation of higher oxidative stress resulting from UBP10 inactivation, an increase of protein carbonylation has been found in the ubp10 stationary phase cells compared with sir2 ones. Moreover, Calorie Restriction had a salutary effect for both mutants by reducing carbonylated proteins accumulation. Remarkably, in the replicative aging model, whereas SIR2 inactivation resulted in a failure to establish damage asymmetry, the Sir2-dependent damage inheritance is maintained in the ubp10 mutant which copes with the increased oxidative damage by retaining it in the mother cells. This indicates that both Ubp10 and a correct association of Sir2 with the silenced chromatin are not necessary in such a process but also suggests that additional Sir2 activities on non-chromatin substrates are involved in the establishment of damage asymmetry.CI - Copyright (c) 2010. Published by Elsevier B.V.
|Status: Published||Type: Journal Article||PubMed ID: 20211662|
Topics addressed in this paper
Number of different genes curated to this paper: 8
- To go to the Locus page for a gene, click on the gene name.