Probing nucleosome function: A highly versatile library of synthetic histone H3 and H4 mutants
Ontology highlight
ABSTRACT:
ORGANISM(S): Saccharomyces cerevisiae
PROVIDER: GSE10860 | GEO | 2008/09/19
SECONDARY ACCESSION(S): PRJNA107359
REPOSITORIES: GEO
Similar Datasets
Project description:The structural integrity of the nucleosome is central to regulation of DNA metabolism and transcription. We describe a library of 486 systematic histone H3 and H4 substitution and deletion mutants in Saccharomyces cerevisiae that probe the contribution of each residue to nucleosome function and can be episomal or genomically integrated. We tagged each mutant histone gene with unique molecular barcodes, facilitating identification of mutant pools through barcode amplification, labeling, and microarray hybridization. We probed fitness contributions of each residue to chemical perturbagens of chromosome integrity and transcription, mapping global patterns of chemical sensitivities and requirements for three forms of transcriptional silencing onto the nucleosome surface. Lethal mutants were surprisingly rare and of distinct types; one set of mutations mapped precisely to the DNA interaction surface. The barcode microarrays were useful for scoring complex phenotypes such as competitive fitness in a chemostat, proficiency of DNA repair, and synthetic genetic interactions. Keywords: genetic modification These nine datasets characterize a microarray platform repurposed for profiling a barcoded comprehensive library of synthetic histone mutants. The first two datasets establish the wide dynamic range and high sensitivity and specificity of data from this platform. The other seven datasets demonstrate the usefulness of this technology for scoring subtle and complex phenotypes of the histone H3 and H4 alleles in this library.
2008-09-18 | E-GEOD-10860 | biostudies-arrayexpress
Project description:Nucleosome structure directly influences gene transcription. However, the function of each histone residue remains largely unknown. Here we profiled gene expression changes upon the mutation of individual residues of histone H3 and H4. Histone residues grouped by expression change similarity displayed overall structural relevance. This regulatory functional map of the core histones led to novel findings. First, the residues specific to each histone family tend to be more influential than those commonly found among different histones. Second, unlike histone acetylations, H3K4 trimethylation does not appear to be prerequisite for gene activation. Third, H3Q5 has been newly identified for its putative interactions with many chromatin regulators for transcription control. Lastly, the nucleosome lateral surface seems to play a key role through interactions with the surrounding DNA. Remarkably, we discovered a novel role for H3K56 in chromatin dynamics. The deletion of this residue, but not the alteration of acetylation states, caused a genome-wide decrease in nucleosome mobility and stabilized nucleosome positioning near transcription start and end sites. Occupying the DNA entry/exit site, H3K56 is thought to modulate nucleosome sliding along DNA. Taken together, genomics approaches such as microarray and deep sequencing prove valuable for mapping the function of histone residues. Performing Mnase-seq for six histone mutants and two wild-types in Saccharomyces cerevisiae
2012-12-05 | E-GEOD-29026 | biostudies-arrayexpress
Project description:Nucleosome structure directly influences gene transcription. However, the function of each histone residue remains largely unknown. Here we profiled gene expression changes upon the mutation of individual residues of histone H3 and H4. Histone residues grouped by expression change similarity displayed overall structural relevance. This regulatory functional map of the core histones led to novel findings. First, the residues specific to each histone family tend to be more influential than those commonly found among different histones. Second, unlike histone acetylations, H3K4 trimethylation does not appear to be prerequisite for gene activation. Third, H3Q5 has been newly identified for its putative interactions with many chromatin regulators for transcription control. Lastly, the nucleosome lateral surface seems to play a key role through interactions with the surrounding DNA. Remarkably, we discovered a novel role for H3K56 in chromatin dynamics. The deletion of this residue, but not the alteration of acetylation states, caused a genome-wide decrease in nucleosome mobility and stabilized nucleosome positioning near transcription start and end sites. Occupying the DNA entry/exit site, H3K56 is thought to modulate nucleosome sliding along DNA. Taken together, genomics approaches such as microarray and deep sequencing prove valuable for mapping the function of histone residues. Microarray analysis was performed for 123 histone mutants and four wild-types as two reaplications of H3 and H4 of Saccharomyces ceravisiae.
2012-12-05 | E-GEOD-29059 | biostudies-arrayexpress
Project description:Nucleosome structure directly influences gene transcription. However, the function of each histone residue remains largely unknown. Here we profiled gene expression changes upon the mutation of individual residues of histone H3 and H4. Histone residues grouped by expression change similarity displayed overall structural relevance. This regulatory functional map of the core histones led to novel findings. First, the residues specific to each histone family tend to be more influential than those commonly found among different histones. Second, unlike histone acetylations, H3K4 trimethylation does not appear to be prerequisite for gene activation. Third, H3Q5 has been newly identified for its putative interactions with many chromatin regulators for transcription control. Lastly, the nucleosome lateral surface seems to play a key role through interactions with the surrounding DNA. Remarkably, we discovered a novel role for H3K56 in chromatin dynamics. The deletion of this residue, but not the alteration of acetylation states, caused a genome-wide decrease in nucleosome mobility and stabilized nucleosome positioning near transcription start and end sites. Occupying the DNA entry/exit site, H3K56 is thought to modulate nucleosome sliding along DNA. Taken together, genomics approaches such as microarray and deep sequencing prove valuable for mapping the function of histone residues. SUBMITTER_CITATION: Global Mapping of the Regulatory Interactions of Histone Residues, Epigenomics Keystone Symposium, January 21th (2012).
2012-12-05 | GSE29059 | GEO
Project description:Nucleosome structure directly influences gene transcription. However, the function of each histone residue remains largely unknown. Here we profiled gene expression changes upon the mutation of individual residues of histone H3 and H4. Histone residues grouped by expression change similarity displayed overall structural relevance. This regulatory functional map of the core histones led to novel findings. First, the residues specific to each histone family tend to be more influential than those commonly found among different histones. Second, unlike histone acetylations, H3K4 trimethylation does not appear to be prerequisite for gene activation. Third, H3Q5 has been newly identified for its putative interactions with many chromatin regulators for transcription control. Lastly, the nucleosome lateral surface seems to play a key role through interactions with the surrounding DNA. Remarkably, we discovered a novel role for H3K56 in chromatin dynamics. The deletion of this residue, but not the alteration of acetylation states, caused a genome-wide decrease in nucleosome mobility and stabilized nucleosome positioning near transcription start and end sites. Occupying the DNA entry/exit site, H3K56 is thought to modulate nucleosome sliding along DNA. Taken together, genomics approaches such as microarray and deep sequencing prove valuable for mapping the function of histone residues. SUBMITTER_CITATION: Global Mapping of the Regulatory Interactions of Histone Residues, Epigenomics Keystone Symposium, January 21th (2012).
2012-12-05 | GSE29026 | GEO
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Project description:The Bacillus subtilis membrane contains diacylglycerol-based lipids with at least five distinct headgroups that impart distinct physical and chemical properties to the lipid bilayer. Here, we describe the phenotypic characterization of mutant strains lacking one or more of the following lipids: glycolipids (ugtP mutants), phosphatidylethanolamine (pssA and psd mutants), lysylphosphatidylglycerol (mprF), and cardiolipin (ywnE and ywjE). Alterations of membrane lipid headgroup composition are generally well tolerated by the cell and even severe alterations lead to only modest effects on growth proficiency. Mutants with decreased levels of positively charged lipids display an increased sensitivity to a cationic antimicrobial compounds and cells lacking glycolipids are sensitive to the lantibiotic sublancin and are defective in swarming motility. A quadruple mutant strain (ugtP pssA mprF ywnE), with a membrane comprised predominantly of phosphatidylglycerol, is viable and grows at near wild-type rates, although it forms long, coiled filaments. Transcriptome comparisons identify numerous regulons with altered expression in ugtP mutant cells, the pssA mprF ywnE triple mutant, and the uptP pssA mprF ywnE quadruple mutant. These effects include a general decrease in expression of the SigD and FapR regulons, and increased expression of cell envelope stress responses mediated by ?M and the YvrGHb two-component system. WT vs.ugtP single mutant (U), WT vs. mprFpssAywnE triple mutant (T) or WT vs. ugtPmprFpssAywnE quadruple mutant (Q). Each experiment (WT vs. mutant) was conducted four times using three independent total RNA preparations (3 independent experiement + dye swap). For the 3 datasets used for final analysis wild-type was labeled with Alexa Fluor 555 and mutants with Alexa Fluor 647. For dye swap experiments wild-type was labeled with Alexa Fluor 647 and mutants with Alexa Fluor 555.
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