Nucleosome conformation dictates the histone code
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE150617 | GEO | 2021/05/06
REPOSITORIES: GEO
Similar Datasets
Project description:Background: Histone post-translational modifications (PTMs) constitute a branch of epigenetic mechanisms that can control the expression of eukaryotic genes in a heritable manner. Recent studies have identified several PTM-binding proteins containing diverse specialized domains whose recognition of specific PTM sites leads to gene activation or repression. Here, we present a high-throughput proteogenomic platform designed to characterize the nucleosomal make-up of chromatin enriched with a set of histone PTM-binding proteins known as histone PTM readers. We support our findings with gene expression data correlating to PTM distribution. Results: We isolated human mononucleosomes bound by the bromodomain-containing proteins Brd2, Brd3 and Brd4, and by the chromodomain-containing heterochromatin proteins HP1alpha and HP1beta. Histone PTMs were quantified by mass spectrometry (ChIP-qMS), and their associated DNAs were mapped using deep sequencing. Our results reveal that Brd- and HP1-bound nucleosomes are enriched in histone PTMs consistent with actively transcribed euchromatin and silent heterochromatin, respectively. Data collected using RNA-Seq (GSM301568) show that Brd-bound sites correlate with highly expressed genes. In particular, Brd3 and Brd4 are most enriched on nucleosomes located within HOX gene clusters, whose expression is reduced upon Brd4 depletion by shRNA. Conclusions: Proteogenomic mapping of histone PTM readers, alongside the characterization of their local chromatin environments and transcriptional information, should prove useful for determining how histone PTMs are bound by these readers and how they contribute to distinct transcriptional states. Examination of Brd and HP1 proteins-binding sites in HEK293 cells.
2012-07-31 | E-GEOD-39579 | biostudies-arrayexpress
Project description:Background: Histone post-translational modifications (PTMs) constitute a branch of epigenetic mechanisms that can control the expression of eukaryotic genes in a heritable manner. Recent studies have identified several PTM-binding proteins containing diverse specialized domains whose recognition of specific PTM sites leads to gene activation or repression. Here, we present a high-throughput proteogenomic platform designed to characterize the nucleosomal make-up of chromatin enriched with a set of histone PTM-binding proteins known as histone PTM readers. We support our findings with gene expression data correlating to PTM distribution. Results: We isolated human mononucleosomes bound by the bromodomain-containing proteins Brd2, Brd3 and Brd4, and by the chromodomain-containing heterochromatin proteins HP1alpha and HP1beta. Histone PTMs were quantified by mass spectrometry (ChIP-qMS), and their associated DNAs were mapped using deep sequencing. Our results reveal that Brd- and HP1-bound nucleosomes are enriched in histone PTMs consistent with actively transcribed euchromatin and silent heterochromatin, respectively. Data collected using RNA-Seq (GSM301568) show that Brd-bound sites correlate with highly expressed genes. In particular, Brd3 and Brd4 are most enriched on nucleosomes located within HOX gene clusters, whose expression is reduced upon Brd4 depletion by shRNA. Conclusions: Proteogenomic mapping of histone PTM readers, alongside the characterization of their local chromatin environments and transcriptional information, should prove useful for determining how histone PTMs are bound by these readers and how they contribute to distinct transcriptional states. Comparison of Brd2 and HP1b shRNA knockdown HEK293 cells to control knockdown HEK293 cells.
2012-07-30 | E-GEOD-39580 | biostudies-arrayexpress
Project description:Background: Histone post-translational modifications (PTMs) constitute a branch of epigenetic mechanisms that can control the expression of eukaryotic genes in a heritable manner. Recent studies have identified several PTM-binding proteins containing diverse specialized domains whose recognition of specific PTM sites leads to gene activation or repression. Here, we present a high-throughput proteogenomic platform designed to characterize the nucleosomal make-up of chromatin enriched with a set of histone PTM-binding proteins known as histone PTM readers. We support our findings with gene expression data correlating to PTM distribution. Results: We isolated human mononucleosomes bound by the bromodomain-containing proteins Brd2, Brd3 and Brd4, and by the chromodomain-containing heterochromatin proteins HP1alpha and HP1beta. Histone PTMs were quantified by mass spectrometry (ChIP-qMS), and their associated DNAs were mapped using deep sequencing. Our results reveal that Brd- and HP1-bound nucleosomes are enriched in histone PTMs consistent with actively transcribed euchromatin and silent heterochromatin, respectively. Data collected using RNA-Seq (GSM301568) show that Brd-bound sites correlate with highly expressed genes. In particular, Brd3 and Brd4 are most enriched on nucleosomes located within HOX gene clusters, whose expression is reduced upon Brd4 depletion by shRNA. Conclusions: Proteogenomic mapping of histone PTM readers, alongside the characterization of their local chromatin environments and transcriptional information, should prove useful for determining how histone PTMs are bound by these readers and how they contribute to distinct transcriptional states.
2012-07-31 | GSE39580 | GEO
Project description:Background: Histone post-translational modifications (PTMs) constitute a branch of epigenetic mechanisms that can control the expression of eukaryotic genes in a heritable manner. Recent studies have identified several PTM-binding proteins containing diverse specialized domains whose recognition of specific PTM sites leads to gene activation or repression. Here, we present a high-throughput proteogenomic platform designed to characterize the nucleosomal make-up of chromatin enriched with a set of histone PTM-binding proteins known as histone PTM readers. We support our findings with gene expression data correlating to PTM distribution. Results: We isolated human mononucleosomes bound by the bromodomain-containing proteins Brd2, Brd3 and Brd4, and by the chromodomain-containing heterochromatin proteins HP1alpha and HP1beta. Histone PTMs were quantified by mass spectrometry (ChIP-qMS), and their associated DNAs were mapped using deep sequencing. Our results reveal that Brd- and HP1-bound nucleosomes are enriched in histone PTMs consistent with actively transcribed euchromatin and silent heterochromatin, respectively. Data collected using RNA-Seq (GSM301568) show that Brd-bound sites correlate with highly expressed genes. In particular, Brd3 and Brd4 are most enriched on nucleosomes located within HOX gene clusters, whose expression is reduced upon Brd4 depletion by shRNA. Conclusions: Proteogenomic mapping of histone PTM readers, alongside the characterization of their local chromatin environments and transcriptional information, should prove useful for determining how histone PTMs are bound by these readers and how they contribute to distinct transcriptional states.
2012-07-31 | GSE39579 | GEO
Project description:Elucidation of interactions involving DNA and histone post-translational-modifications (PTMs) is essential for providing insight into complex biological functions. Reader assemblies connected via flexible linkages facilitate avidity and increase affinity, however little is known of the contribution to the recognition process of multiple PTMs due to rigidity in the absence of conformational flexibility. We report here the high resolution crystal structure of the triple-reader module (PHD-Bromo-PWWP) of ZMYND8 which forms a stable unit capable of simultaneously recognizing multiple histone PTMs, while presenting a charged platform for association with DNA. Single domain disruptions destroy the functional network of interactions initiated by ZMYND8, impairing recruitment to sites of DNA damage. Our data establish proof-of-principle that rigidity can be compensated by concomitant DNA and histone PTM interactions, maintaining multivalent engagement of transient chromatin states, thus identifying an important underappreciated role for rigid multivalent reader modules in nucleosome binding and chromatin function.
2016-11-23 | GSE81696 | GEO
Project description:Histone post-translational modifications (PTMs) are frequently co-occurring on the same chromatin domains or even the same molecule. It is now established that these ‘histone codes’ are the result of cross-talk between enzymes that catalyse multiple PTMs with univocal readout as compared to these PTMs in isolation. Here, we performed a comprehensive identification and quantification of histone codes of the malaria parasite, Plasmodium falciparum. We used advanced quantitative middle-down proteomics to identify combinations of PTMs in both the proliferative, asexual stages and transmissible, sexual gametocyte stages of P. falciparum. We provide an updated, high-resolution compendium of 72 PTMs on H3 and H3.3, of which 30 newly identified. Several co-existing PTMs with unique stage distinction was identified, indicating that many of these combinatorial PTMs are associated to specific stages of the parasite life cycle. We focused on the code H3R17me2K18acK23ac for its unique presence in mature gametocytes; chromatin proteomics identified a gametocyte-specific SAGA-like effector complex including the transcription factor AP2-G2 which we associated to this specific histone code, as involved in regulating gene expression in mature gametocytes. Ultimately, this study unveils previously undiscovered histone PTMs and their functional relationship with co-existing partners. These results highlight that investigating chromatin regulation in the parasite using single histone PTM assays might overlook higher order gene regulation for distinct proliferation and differentiation processes.
2022-05-19 | PXD030181 | Pride
Project description:Post-translational modifications (PTMs) on histone proteins regulate genome accessibility and are frequently studied using chromatin immunoprecipitation (ChIP). In ChIP, an antibody putatively specific towards a histone PTM is used to map its genomic locations. ChIP experiments assume perfect antibody-epitope specificity, an assumption previously shown to be problematic, largely through peptide array studies. Among the most well-studied histone PTMs are the mono-, di-, and tri-methylation states of histone H3 lysine 4 (H3K4). While each state has been ascribed different biological functions, the methylation state specificity of antibodies used in these studies has not been systematically interrogated. Here, we use internally calibrated ChIP (ICeChIP) to comprehensively define the specificities of 52 commercially available antibodies marketed to distinguish the three methylation states of H3K4, allowing identification of both high- and low-specificity antibodies. We then conduct ICeChIP-seq with 18 such antibodies of varying specificity. We further find that the sum of H3K4me1 and H3K4me2 across enhancers contacting a promoter correlates strongly with gene expression for all genes, including housekeeping genes, and note that use of low-quality antibodies yields materially different biological interpretations. These results illustrate the way by which variable specificity of commercial antibodies contributes to the “reproducibility crisis” in biological research and demonstrates the need to carefully validate antibodies with techniques appropriate for the intended applications.
2018-09-20 | GSE103543 | GEO
Project description:Post-translational modifications (PTMs) of proteins play critical roles in regulating many cellular events. Antibodies targeting site-specific PTMs are essential tools for detecting and enriching PTMs at sites of interest. However, fundamental difficulties in molecular recognition of both PTM and surrounding peptide sequence have hindered the efficient generation of highly specific anti-PTM antibodies. Furthermore, the widespread use of potentially inconsistent, non-renewable and molecularly undefined antibodies presents experimental challenges thought to contribute to the reproducibility crisis in biomedical research. In this study, we describe the structure-guided development of a platform that efficiently generates potent and selective recombinant antibodies to PTMs that are molecularly-defined and infinitely renewable. Our platform is built on our previous discovery of an unconventional binding mode of anti-PTM antibodies, antigen clasping, where two antigen binding sites cooperatively clasp a single antigen, creating extensive interactions with the antigen and leading to high selectivity and potency. We designed the platform that generates clasping antibodies with two distinct binding units, resulting in efficient generation of antibodies to a set of trimethylated histone H3 with high levels of specificity and affinity. Performance comparison in chromatin immunoprecipitation (ChIP), a common application in epigenomics, revealed that an anti-H3K27me3 clasping antibody exhibited superior specificity to a widely-used conventional antibody and captured symmetric and asymmetric nucleosomes in a less biased manner. We further generated clasping antibodies to phosphotyrosine antigens by using the same principle. These results suggest the broad applicability of our platform to generating high-performance clasping antibodies to diverse PTMs.
2024-12-02 | GSE270275 | GEO
Project description:Histone posttranslational modifications (PTMs) are important for regulating various DNA-templated processes. Emerging evidence suggests a critical involvement of the previously less-explored histone PTMs in gene activity regulation. Here, we report the existence of a new histone PTM in the mammalian cells, hydroxylation of H3 proline 16 (H3P16-OH) catalyzed by EglN2, a proline hydroxylase. We show that EglN2-mediated H3P16-OH enhances direct binding of Lysine-Specific Demethylase 5A (KDM5A) with its substrate, H3 lysine 4 trimethylation (H3K4me3), resulting in enhanced chromatin recruitment of KDM5A and decrease of H3K4me3 at target genes. Genome-wide mapping by CUT&RUN in multiple mammalian cell models reveals a functional connection between EglN2, H3P16-OH, KDM5A and H3K4me3. Integrated analysis with RNA-Seq also identifies distinct subsets of genes that are regulated through H3P16-OH in different cell lines. This study therefore demonstrates a new player of the “histone code” by revealing a role of H3P16-OH in regulating gene expression in mammalian cells.
2022-08-02 | GSE179112 | GEO
Project description:Histone posttranslational modifications (PTMs) are important for regulating various DNA-templated processes. Emerging evidence suggests a critical involvement of the previously less-explored histone PTMs in gene activity regulation. Here, we report the existence of a new histone PTM in the mammalian cells, hydroxylation of H3 proline 16 (H3P16-OH) catalyzed by EglN2, a proline hydroxylase. We show that EglN2-mediated H3P16-OH enhances direct binding of Lysine-Specific Demethylase 5A (KDM5A) with its substrate, H3 lysine 4 trimethylation (H3K4me3), resulting in enhanced chromatin recruitment of KDM5A and decrease of H3K4me3 at target genes. Genome-wide mapping by CUT&RUN in multiple mammalian cell models reveals a functional connection between EglN2, H3P16-OH, KDM5A and H3K4me3. Integrated analysis with RNA-Seq also identifies distinct subsets of genes that are regulated through H3P16-OH in different cell lines. This study therefore demonstrates a new player of the “histone code” by revealing a role of H3P16-OH in regulating gene expression in mammalian cells.
2022-08-02 | GSE179108 | GEO