Project description:Telomere chromatin structure is pivotal for maintaining genome stability by regulating the binding of telomere-associated proteins and inhibition of a DNA damage response. In yeast, the silent information regulator (Sir) proteins bind to terminal telomeric repeats and to subtelomeric X-elements resulting in histone deacetylation and transcriptional silencing. Herein, we show that sir2 mutant strains display a very specific loss of a nucleosome residing in the X-element. Most yeast telomeres contain an X-element and the nucleosome occupancy defect in sir2 mutants is remarkably consistent between different telomeres.
Project description:We expressed human RECQL5 in the model organism Sacharomyces cerevisiae. We found that RECQL5 overexpression in yeast leads to cell growth inhibition and increased genotoxic sensitivity. We carried-out transcriptome analysis of yeast strains overexpressing human RECQL5 helicase to explore its impact on gene expression.
Project description:Aneuploidy and aging are correlated; however, a causal link between these two phenomena has remained elusive. Here we show that yeast disomic for a single native yeast chromosome generally have a decreased replicative lifespan. In addition, the extent of this lifespan deficit correlates with the size of the extra chromosome. We identified a mutation in BUL1 that rescues both the lifespan deficit and a protein trafficking defect in yeast disomic for chromosome 5. Bul1 is an E4 ubiquitin ligase adaptor involved in a protein quality-control pathway that targets membrane proteins for endocytosis and destruction in the lysosomal vacuole thereby maintaining protein homeostasis. Concurrent suppression of the aging and trafficking phenotypes suggests that disrupted membrane protein homeostasis in aneuploid yeast may contribute to their accelerated aging. The data reported here demonstrate that aneuploidy can impair protein homeostasis, shorten lifespan, and may contribute to age-associated phenotypes.
Project description:Global gene expression on yeast cells was determined after a drug induced inhibition of GGTase I by treating yeast cells with GGTI298 (Cabiochem). GGTI298 treated cells were grown for 2 generations to exponential phase in parallel with untreated cells. RNA was extracted, subsequently cDNAs were labelled and hybridized on UHN Y6.4k4 arrays. Replicates with dye-swap of the experiments were generated. Results enabled us to identify the genome-wide effects after drug-induced GGTase I inhibition
Project description:Effect of FLO8 or MSS11 deletion and -overexpression on yeast transcript profiles compared to wild type in laboratory yeast strains Σ1278b and S288c.
