Global Identification of Protein PTMs in a Single-pass Database Search
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
SUBMITTER: Anthony Cesnik
PROVIDER: E-GEOD-59956 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Bottom-up proteomics database search algorithms used for peptide identification cannot comprehensively identify posttranslational modifications (PTMs) in a single-pass because of high false discovery rates (FDRs). A new approach to database searching enables Global PTM (G-PTM) identification by exclusively looking for curated PTMs, thereby avoiding the FDR penalty experienced during conventional variable modification searches. We identified nearly 2500 unique, high-confidence modified peptides comprising 31 different PTM types in single-pass database searches.
2015-07-31 | GSE59956 | 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. 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:Post-translational modifications (PTMs) of proteins, such as acetylation or phosphorylation, represent a huge untapped source of targets of great biological and therapeutic potential, but their validation can only be indirect. PTMs cannot be selectively hit by the powerful nucleic-acid based interference approaches. Antibodies represent a class of molecules that could be exploited to selectively target PTMs. However, currently it is not possible to systematically derive antibodies that selectively bind PTMs of a native protein and work intracellularly to achieve a native PTM-selective interference. We developed the Post-translational Intracellular Silencing Antibody technology (P.I.S.A.), a new method for the selection of intrabodies targeting the native PTM version of proteins and their use for PTM targeting in cells. We used PISA to select an intrabody against acetylated-K9-H3 Histone (ScFv-58F). Microarray study is aimed at the investigation of ScFv-58F-specific changes in gene expression in yeast, in comparison to yeast expressing a control intrabody (ScFv-112A, anti-acetyl-Integrase, selected with PISA), and to a wild type yeast.
2016-11-14 | GSE86954 | GEO
Project description:Histone post-translational modifications (PTMs) play a critical role in chromatin regulation. It has been proposed that these PTMs form localized “codes” that are read by specialized domains (reader domains) in chromatin associated proteins (CAPs) to regulate downstream function. Substantial effort has been made to define [CAP - histone PTM] specificity, and in doing so to decipher the histone code. However, this has largely been done using a reductive approach of isolated reader domains and histone peptides, with the assumption that PTM readout is unaffected by any higher order considerations. Here we show that histone PTM specificity is in fact dependent on nucleosomal context, necessitating we re-define the ‘histone code’ concept and further interrogate it at the nucleosomal level.
2021-05-06 | GSE150617 | GEO
Project description:Isobaric tag-based sample multiplexing strategies are extensively used for global protein abundance profiling. However, such analyses are often confounded by ratio compression resulting from the co-isolation, co-fragmentation, and co-quantification of co-eluting peptides, termed “interference.” Recent analytical strategies incorporating ion mobility and real-time database searching have helped to alleviate interference, yet further assessment is needed. Here, we present the Strain-Specific Peptide (SSP) standard, a TMTpro-tagged reference sample that leverages the genetic variation in the proteomes of eight phylogenetically divergent mouse strains. Typically, a peptide with a missense mutation will have a different mass and retention time than the reference or native peptide. TMT reporter ion signal for the native peptide in strains that encode the mutant peptide suggests interference which can be quantified and assessed using the interference-free index (IFI). We showcase the SSP standard by investigating interference in three common data acquisition methods and by testing the improvements in the IFI when using ion mobility-based gas phase fractionation. In addition, we provide a user-friendly, online viewer to visualize the data and streamline calculation of the IFI. The SSP standard will aid in developing and optimizing isobaric tag-based experiments.
2021-04-03 | PXD023203 | Pride
Project description:Post-translational modifications (PTMs) change protein structures and functions. Methods for the simultaneous enrichment of multiple PTM types can maximize coverage in analyses. We present a protocol using dual-functional Ti(IV)-immobilized metal affinity chromatography followed by mass spectrometry for the simultaneous enrichment and analysis of protein N-glycosylation and phosphorylation in pancreas tissues.
2022-08-12 | PXD033065 | Pride
Project description:Both genetic and environmental factors are implicated in Type 1 Diabetes (T1D). Since environmental factors can trigger epigenetic changes, we hypothesized that variations in histone posttranslational modifications (PTMs) at the promoter/enhancer regions of T1D susceptible genes may be associated with T1D. We therefore evaluated histone PTM variations at known T1D susceptible genes in blood cells from T1D patients versus healthy non-diabetic controls, and explored their connections to T1D. We used the chromatin-immunoprecipitation-linked-to-microarray approach to profile key histone PTMs, including H3-lysine-4 trimethylation (H3K4me3), H3K27me3, H3K9me3, H3K9 acetylation (H3K9Ac) and H4K16Ac at genes within the T1D susceptible loci in lymphocytes, and H3K4me3, H3K9me2, H3K9Ac and H4K16Ac at the IDDM1 region in monocytes of T1D patients and healthy controls separately. We screened for potential variations in histone PTMs using computational methods to compare datasets from T1D and controls. Interestingly, we observed marked variations in H3K9Ac levels at the upstream regions of HLA-DRB1 and HLA-DQB1 within the IDDM1 locus in T1D monocytes relative to controls. Additional experiments with THP-1 monocytes demonstrated increased expression of HLA-DRB1 and HLA-DQB1 in response to interferon- and TNF-treatment that were accompanied by changes in H3K9Ac at the same promoter regions as that seen in the patient monocytes. These results suggest that the H3K9Ac status of HLA-DRB1 and HLA-DQB1, two genes highly associated with T1D, may be relevant to their regulation and transcriptional response towards external stimuli. Thus, the promoter/enhancer architecture and chromatin status of key susceptible loci could be important determinants in their functional association to T1D susceptibility. We evaluated histone PTM variations at known T1D susceptible genes in blood cells from T1D patients versus healthy non-diabetic controls, and explored their connections to T1D. We used the ChIP-chip approach to profile key histone PTMs, including histone H3K4me3, H3K27me3, H3K9me3, H3K9 acetylation (H3K9Ac) and H4K16Ac, at genes within the T1D susceptible loci in lymphocytes.
2012-05-31 | E-GEOD-36402 | biostudies-arrayexpress