Project description:The nucleosome plays a central role in genome regulation. Traditional methods for mapping nucleosomes depend on the resistance of the nucleosome core to micrococcal nuclease (MNase). However, the lengths of the protected DNA fragments are heterogeneous, limiting the accuracy of nucleosome position information. To resolve this problem, we removed residual linker DNA by simultaneous digestion of yeast chromatin with MNase and exonuclease III (ExoIII). Paired-end sequencing of mono-nucleosomes revealed not only core particles (145-147 bp), but also intermediate particles in which ~8 bp project from one side (154 bp) or both sides (161 bp) of the nucleosome core. We term these particles "pseudo-chromatosomes" because they are present in yeast lacking linker histone. They are also observed after MNase-ExoIII digestion of chromatin reconstituted using recombinant core histones. We propose that the pseudo-chromatosome provides a DNA framework to facilitate H1 binding. Comparison of budding yeast nucleosome sequences obtained using micrococcal nuclease (MNase-seq) and MNase + exonuclease III (ExoIII) (MNase-ExoIII-seq): wild type cells and hho1-null cells. Nucleosome sequences from native chromatin and H1-depleted chromatin from mouse liver. Nucleosome sequences from a plasmid reconstituted into nucleosomes using recombinant yeast histones or native chicken erythrocyte histones.
Project description:To investigate how exogenous DNA concatemerizes to form episomal artificial chromosomes (ACs), acquire equal segregation ability and maintain stable holocentromeres, we injected DNA sequences with different features, including sequences that are repetitive or complex, and sequences with different AT-contents, into the gonad of Caenorhabditis elegans to form ACs in embryos, and monitored AC mitotic segregation. We demonstrated that AT-poor sequences (26% AT-content) delayed the acquisition of segregation competency of newly formed ACs. We also co-injected fragmented Saccharomyces cerevisiae genomic DNA, differentially expressed fluorescent markers and ubiquitously expressed selectable marker to construct a less repetitive, more complex AC. We sequenced the whole genome of a strain which propagates this AC through multiple generations, and de novo assembled the AC sequences. We discovered CENP-AHCP-3 domains/peaks are distributed along the AC, as in endogenous chromosomes, suggesting a holocentric architecture. We found that CENP-AHCP-3 binds to the unexpressed marker genes and many fragmented yeast sequences, but is excluded in the yeast extremely high-AT-content centromeric and mitochondrial DNA (> 83% AT-content) on the AC. We identified A-rich motifs in CENP-AHCP-3 domains/peaks on the AC and on endogenous chromosomes, which have some similarity with each other and similarity to some non-germline transcription factor binding sites.
Project description:The sequence specificity of DNA-binding proteins is the primary mechanism by which the cell recognizes genomic features. Here, we describe systematic determination of yeast transcription factor DNA-binding specificities. We obtained binding specificities for 112 DNA-binding proteins representing 19 distinct structural classes. One-third of the binding specificities have not been previously reported. Several binding sequences have striking genomic distributions relative to transcription start sites, supporting their biological relevance and suggesting a role in promoter architecture. Among these are Rsc3 binding sequences, containing the core CGCG, which are found preferentially ~100 bp upstream of transcription start sites. Mutation of RSC3 results in a dramatic increase in nucleosome occupancy in hundreds of proximal promoters containing a Rsc3 binding element, but has little impact on promoters lacking Rsc3 binding sequences, indicating that Rsc3 plays a broad role in targeting nucleosome exclusion at yeast promoters. Keywords: Protein binding microarrays, DNA, proteins
2008-12-26 | GSE12349 | GEO
Project description:MinION rDNA sequences of yeast mock communities.
Project description:We report the high-throughput profiling of histone modification (H3K9me2) or histone variant CNEP-A/Cnp1 in fission yeast Schizosaccharomyces pombe. By obtaining 1-10 ng immunoprecipitated DNA, we generated genome-wide H3K9me2 or CENP-A/Cnp1 maps of wild type strains carrying the inactivated Centromere 1 or Centromere 2 or Cnp1 spreading in fission yeast with a reporter gene ura4 cassette inserted into the right side of the repetitive sequences of Chromosome 1 . We find that neocemtromeres are formed preferably at pericentromeric regions ubiquitously and asymmetrically in all three centromeres of these indicated strains.
2019-09-28 | GSE131225 | GEO
Project description:Illumina MiSeq rDNA sequences of yeast mock communities.
| PRJNA862334 | ENA
Project description:Transcriptomic sequences of Yeast in co-culture metagenome
| PRJNA510487 | ENA
Project description:Transcriptomic sequences of Yeast in co-culture metagenome
Project description:GwAAP: A Genome-wide Amino Acid coding-decoding quantitative Proteomic system was designed in which each protein could be assigned with a distinct code. Using synthetic biology technology, the amino acids codes were coded in N terminal of the corresponding proteins in the genome of yeast (Saccharomyces cerevisiae), so that the copy number of the code sequences were identical with the targeted proteins in yeast. The code sequences were enriched by HA antibody and decoded and quantified by mass spectrometry strategy. In general, this method increased the detection sensitivity by peptide enrichment, which reduced the dynamic range and the complexity of proteomics. In addition, coding sequence with similar physical and chemical properties resulted in the comparable linear signal response of the mass spectrum, which significantly improve the accuracy of proteomic quantification.