Project description:We report DNA content of yeast strains that are growing asynchronously or treated with hydroxyurea (HU). We selected two strains from our Epi-Decoder library, that are wild-type but have BAR1 or RPO21 TAP-tagged. This reveals that HU-treated samples have peaks in DNA content representing stalled replication forks.
Project description:The Saccharomyces cerevisiae MYO1 gene encodes the myosin type II heavy chain (Myo1p), a protein required for normal cytokinesis in budding yeast. Deletion of the MYO1 gene prevents actomyosin-driven cytokinesis thereby activating an alternative mechanism that involves the synthesis of a remedial septum. Myo1p deficiency in yeast (myo1) also causes the formation of attached cells, abnormal budding patterns, formation of enlarged and elongated cells, increased osmotic sensitivity, delocalized chitin deposition, and increased chitin synthesis. To determine how the differential expression of genes is related to these diverse phenotypes, we analyzed the global mRNA expression profile of myo1 strains. Global mRNA expression profiles of myo1 strains and their corresponding wild type controls were obtained by hybridization to yeast oligonucleotide microarrays. Results for selected genes were confirmed by real time RT-PCR. A total of 547 differentially expressed genes were identified with 263 up-regulated and 284 down regulated genes in the myo1 strains. Gene set enrichment analysis revealed the significant over-representation of genes in the protein biosynthesis and stress response categories. Genes involved in cell wall assembly (GAS1, PSA1, CIS3, FIT1, WSC2), MAP kinase activity (SLT2), Rho1p Guanine Exchange Factor (ROM1), and regulation of cell proliferation (RAS1) were also differentially expressed in myo1 strains. Conclusions: We have presented a global mRNA expression analysis of yeast myo1 strains and hypothesized about possible correlations with morphological and biochemical phenotypes observed in these strains. We report 547 differentially regulated genes in the myo1 mutant strains. Genes involved in the control of cell proliferation, protein synthesis and maturation, DNA replication, and cell division processes were largely down regulated, suggesting a mechanism for delayed cell cycle progression and growth that involves coordinated regulation of these processes in myo1 strains. Other genes involved in the cellular response to cell wall stress and cell wall organization were largely up-regulated suggesting that cell wall biogenesis is important for the completion of cytokinesis and cell wall morphogenetic processes that may also be affected by myosin II deficiency. Gene set enrichment analysis indicates that stress response and protein biosynthesis gene categories are inversely correlated in this mutant. Keywords: Comparative genomic hybridization
Project description:Using RNA-seq, we analyzed the transcriptomes of isogenic haploid (MATa) and tetraploid (MATaaaa) budding yeast strains in the Sigma 1278b background and identified genes whose regulation was altered by ploidy.
Project description:genomic localization of the budding yeast cohesin complex was mapped in mitotically arrested cells by Mcd1 ChIP followed by hybridization to high-density tiled microarrays
Project description:RNAi, a gene-silencing pathway triggered by double-stranded RNA, is conserved in diverse eukaryotic species but has been lost in the model budding yeast, Saccharomyces cerevisiae. We report that RNAi is present in other budding-yeast species, including Saccharomyces castellii and Candida albicans. These species use noncanonical Dicer proteins to generate siRNAs, which mostly correspond to transposable elements and Y´ subtelomeric repeats. In S. castellii, RNAi mutants are viable but have excess Y´ mRNA levels. In S. cerevisiae, introducing Dicer and Argonaute of S. castellii restores RNAi, and the reconstituted pathway silences endogenous retrotransposons. These results identify a novel class of Dicer proteins, bring the tool of RNAi to the study of budding yeasts, and bring the tools of budding yeast to the study of RNAi.
Project description:Multi-genome, time series transcriptome measurements across the budding yeast cell cycle 378 genome-wide microarray measurements, 18 timepoints, nine strains of S. cerevisiae and one strain of S. paradoxus