Project description:To investigate nuclear DNA replication enzymology in vivo, we have studied Saccharomyces cerevisiae strains containing a pol2-16 mutation that inactivates the catalytic activities of DNA polymerase δ (Pol δ). Although pol2-16 mutants survive, their spore colonies are very tiny, with increased doubling time, larger than normal cells, aberrant nuclei, and rapid suppressor mutation accumulation. These phenotypes reveal a severe growth defect that is distinct from that of strains that lack Pol δ proofreading (pol2-4), consistent with the idea that Pol δ is the major leading strand replicase. Ribonucleotides are also incorporated into the pol2-16 genome in patterns consistent with leading strand replication by Pol δ when Pol δ is absent. More importantly, ribonucleotide distributions at replication origins suggest that in strains encoding all three replicases, Pol δ contributes to initiation of leading-strand replication. We describe two possible models.
Project description:We have employed whole genome microarray expression profiling as a discovery platform to identify genes implicated in the resistance to cobalt in Saccharomyces cerevisiae. The evolved strains and the wild type were harvested in exponential phase WT (CEN.PK), the evolved strain (CI25E) and the evolved strain delta Cot1 harvested in exponential phase (DO 600nm=3) ; three independant replicate for each.
Project description:The goal of these experiments was to determine the global expression profile response of budding yeast to a genetic block of Farnesyl Transferase (FTase). We blocked this enzyme using cells that harbour a deletion of the RAM1 gene, which encodes one of the two subunits of FTase. We compared the cells of the strain Delta ram1 with isogenic wild-type cells, grown in parallel cultures. Cells were grown for 2 generations to exponential phase. 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 genetically-induced FTase block
