Saccharomyces cerevisiae
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA117439 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:In budding yeast, telomeres and the mating type (HM) loci are found in a heterochromatin-like silent structure initiated by Rap1 and extended by the interaction of Sir (Silencing Information Regulator) proteins with histones. Binding data demonstrate that both the H3 and H4 N terminal domains required for silencing in vivo interact directly with Sir3 and Sir4 in vitro. The role of H4 lysine 16 deacetylation is well established in Sir3 protein recruitment, however that of the H3 N terminal tail has remained unclear. In order to characterize the role of H3 in silent chromatin formation and compare it to H4 we have generated comprehensive high resolution genome-wide binding maps of heterochromatin proteins. We find that H4 lysine 16 deacetylation is required for the recruitment and spreading of heterochromatin proteins at all telomeres and HM loci. In contrast the H3 N terminus is required for neither recruitment nor spreading of Sir proteins. Instead, deletion of the H3 tail leads to increased accessibility within heterochromatin of an ectopic bacterial dam methylase and the decreased mobility of an HML heterochromatic fragment in sucrose gradients. These findings indicate an altered chromatin structure. We propose that Sir proteins recruited by the H4 tail then interact with the H3 tail to form a higher order silent chromatin structure.
2009-08-01 | GSE16742 | GEO
Project description:This model is described in the article:
Kinetics of histone gene expression during early development of Xenopus laevis.
Koster JG, Destrée OH and Westerhoff HV. J Theor Biol.
1988 Nov 21;135(2):139-67. PMID: 3267765
Abstract:
Using literature data for transcriptional and translational rate constants, gene copy numbers, DNA concentrations, and stability constants, we have calculated the expected concentrations of histones and histone mRNA during embryogenesis of Xenopus laevis. The results led us to conclude that: (i) for X. laevis the gene copy number of the histone genes is too low to ensure the synthesis of sufficient histones during very early development, inheritance from the oocyte of either histone protein or histone mRNA (but not necessarily both) is necessary; (ii) from the known storage of histones in the oocyte and the rates of histone synthesis determined by Adamson and Woodland (1977), there would be sufficient histones to structure the newly synthesized DNA up to gastrulation but not thereafter (these empirical rates of histone synthesis may be underestimates); (iii) on the other hand, the amount of H3 mRNA recently observed during early embryogenesis (Koster, 1987, Koster et al., 1988) could direct a higher and sufficient synthesis of H3 protein, also after gastrulation. We present a quantitative model that accounts both for the observed H3 mRNA concentration as a function of time during embryogenesis and for the synthesis of sufficient histones to structure the DNA throughout early embryogenesis. The model suggests that X. laevis exhibits a major (i.e. some 14-fold) reduction in transcription of histone genes approximately 11 hours after fertilization. This reduction could be due to a decrease in the number of transcribed histone genes, a decreased rate constant of transcription with continued transcription of all the histone genes, and/or a reduction in the time during the cell cycle in which histone mRNA synthesis takes place. Alternatively, the histone mRNA stability might decrease approximately 16-fold 11 hours after fertilization.
This model originates from BioModels Database: A Database of Annotated Published Models. It is copyright (c) 2005-2011 The BioModels.net Team.
To the extent possible under law, all copyright and related or neighbouring rights to this encoded model have been dedicated to the public domain worldwide. Please refer to CC0 Public Domain Dedication
for more information.
In summary, you are entitled to use this encoded model in absolutely any manner you deem suitable, verbatim, or with modification, alone or embedded it in a larger context, redistribute it, commercially or not, in a restricted way or not..
To cite BioModels Database, please use: Li C, Donizelli M, Rodriguez N, Dharuri H, Endler L, Chelliah V, Li L, He E, Henry A, Stefan MI, Snoep JL, Hucka M, Le Novère N, Laibe C (2010) BioModels Database: An enhanced, curated and annotated resource for published quantitative kinetic models. BMC Syst Biol., 4:92.
2005-01-01 | MODEL5954483266 | BioModels
Project description:Histones are among the most conserved proteins known, but organismal differences do exist. In this study we examined the contribution that divergent amino acids within histone H3 make to cell growth and chromatin structure in S. cerevisiae. We show that, while amino acids that define histone H3.3 are dispensable for yeast growth, substitution of residues within the histone H3 alpha 3 helix with the human counterparts results in a severe growth defect. Mutations within this domain also result in altered nucleosome positioning, both in vivo and in vitro, which is accompanied by increased preference for nucleosome favoring sequences. These results suggest that divergent amino acids within the histone H3 alpha 3 helix play organismal roles in defining chromatin structure. Mnase-seq for two replicates each of wildtype and H3 c-terminal mutants.
2015-11-10 | E-GEOD-73425 | biostudies-arrayexpress
Project description:Histones are among the most conserved proteins known, but organismal differences do exist. In this study we examined the contribution that divergent amino acids within histone H3 make to cell growth and chromatin structure in S. cerevisiae. We show that, while amino acids that define histone H3.3 are dispensable for yeast growth, substitution of residues within the histone H3 alpha 3 helix with the human counterparts results in a severe growth defect. Mutations within this domain also result in altered nucleosome positioning, both in vivo and in vitro, which is accompanied by increased preference for nucleosome favoring sequences. These results suggest that divergent amino acids within the histone H3 alpha 3 helix play organismal roles in defining chromatin structure.
2015-11-10 | GSE73425 | GEO
Project description:The aim of this study is to analyze the distribution of the modified histones in and around peri-centromeric heterochromatin at high resolutions for understanding the molecular nature of the heterochromatic genes and euchromatin-heterochromatin transition. Since heterochromatin is repeat-rich, stringent repeat-filtering was applied in the genome-tiling array design. When possible, parallel analyses were performed with two different types of reference controls, namely total genomic DNA and histone H3 C-terminus ChIP.
2010-06-29 | E-GEOD-7839 | biostudies-arrayexpress
Project description:SETMAR regulates gene expression and modulates higher order chromatin structure
| PRJNA642400 | ENA
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. Experiment Overall Design: Comparison of genes whose mRNA levels are affected in histone H4R45H mutant yeast strains compared to wild type yeast strain WY139. This comparison reveals how subtle change in a single amino acid residue in core domain of histone H4 affects gene expression profile in yeast.
2008-10-20 | E-GEOD-11282 | biostudies-arrayexpress
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
2008-06-23 | GSE11282 | GEO
Project description:SETMAR regulates gene expression and modulates higher order chromatin structure [II]
| PRJNA642402 | ENA
Project description:SETMAR regulates gene expression and modulates higher order chromatin structure [I]
| PRJNA642403 | ENA