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:Total RNA samples from three replicate cultures of wild type and mutant yeast strains was isolated and expression profile done using Affymetrix arrays. Comparsion between the samples indicate how mutation in a single amino acid residue in histone H4 (H4R45H) affects gene expression in yeast. Such a mutation in histone H4 is known to generate a specific class of mutants called SWI/SNF independent (SIN) mutants, and the mutants were identified by their ability to carry out transcription in the absence of yeast chromatin remodeling complex SWI/SNF. SIN mutations are known to affect higher order chromatin structure and the comparative expression profile would help identification of genes which get affected by such altered chromatin landscape. Keywords: mutant analysis
Project description:Transcriptional profiles on different yeast strain mutants (DEgd2/1, DEgd2/Btt1)were identified by microarray analysis comparing total mutant RNA vs wild type RNA.
Project description:We performed massive screening of the genes in yeast that were involved in the tolerance to isopropanol using the non-essential genes deleted yeast collection, and identified sixty-five disruptants that grew slower than the wild type strain in the presence of isopropanol. The isopropanol sensitive mutants were tested to know their behaviour under other alcohol stresses. Besides, we conducted microarray analysis to reveal the transcriptional response to isopropanol stress in yeast. Our results certainly provide new insights into yeast response to C3 alcohol isopropanol.
