Epigenetic regulation of DNA repair pathway choice by macroH2A1 splice variants ensures genome stability
Ontology highlight
ABSTRACT:
INSTRUMENT(S): Orbitrap Fusion
ORGANISM(S): Homo Sapiens (ncbitaxon:9606)
SUBMITTER: 
Philipp Oberdoerffer
PROVIDER: MSV000085541 | MassIVE | Wed Jun 03 07:36:00 BST 2020
REPOSITORIES: MassIVE
Similar Datasets
Project description:The inactive X chromosome (Xi) is inherently susceptible to genomic aberrations. Replication stress (RS) has been proposed as an underlying cause, but the mechanisms that protect from Xi instability remain unknown. Here, we show that macroH2A1.2, an RS-protective histone variant enriched on the Xi, is required for Xi integrity and female survival. Mechanistically, macroH2A1.2 counteracts its structurally distinct and equally Xi-enriched alternative splice variant, macroH2A1.1. Comparative proteomics identified a role for macroH2A1.1 in alternative end joining (alt-EJ), which accounts for Xi anaphase defects in the absence of macroH2A1.2. Genomic instability was rescued by simultaneous depletion of macroH2A1.1 or alt-EJ factors, and mice deficient for both macroH2A1 variants harbor no overt female defects. Notably, macroH2A1 splice variant imbalance affected alt-EJ capacity also in tumor cells. Together, these findings identify macroH2A1 splicing as a modulator of genome maintenance that ensures Xi integrity and may, more broadly, predict DNA repair outcome in malignant cells.
| S-EPMC7483679 | biostudies-literature
Project description:Analysis of human macrophage splice variants
| PRJNA448000 | ENA
Project description:Changes in alternative splicing are associated with several pathological conditions, including cancer. Microarrays strategies, which allow for the characterization of thousands of alternative splice forms in a single test, can be applied to identify differential alternative splicing events. In this study, a novel splice array platform was developed, including the design of a high-density oligonucleotide array, a labeling procedure, and an algorithm to identify splice events. The array consists of exon probes and thermodynamically balanced junction probes. Suboptimal probes are tagged and considered in the final analysis. An unbiased labeling protocol was developed using random primers. The algorithm used to distinguish changes in expression from changes in splicing was calibrated using internal non-spliced control sequences. The performance of this splice array was first validated with artificial constructs for CDC6, VEGF, and PCBP4 isoforms. The platform was then applied to the analysis of differential splice forms for 8000 genes in lung cancer samples compared to matched normal lung tissue. The expression of lung cancer-associated splice isoforms was validated by RT-PCR. Overexpression of splice isoforms was identified for genes encoding CEACAM1, FHL-1, MLPH, and SUSD2. None of these splicing isoforms had been previously associated with lung cancer. In conclusion, this highly accurate methodology enables the detection of alternative splicing events in complex biological samples, providing a powerful tool to identify novel diagnostic and prognostic biomarkers for cancer and other pathologies. 20 normal/tumor paired specimens. Tumor samples are from non-small cell lung cancer (NSCLC) whereas normals are from adjacent normal lung tissue.
2010-06-21 | E-GEOD-18346 | biostudies-arrayexpress
Project description:The identifcation of alternatively spliced transcript variants specific to particular biological processes in tumours should increase our understanding of cancer. Hypoxia is an important factor in cancer biology and associated splice variants may present new markers to help with planning treatment. A method was developed to analyse alternative splicing in exon array data, using probeset multiplicity to identify genes with changes in expression across their loci, and a combination of the splicing index and a new metric based on the variation of reliability weighted fold changes to detect changes in the splicing patterns. The approach was validated on a cancer/normal sample dataset in which alternative splicing events had been confirmed using RT-PCR. We then analysed ten head and neck squamous cell carcinomas using exon arrays and identified differentially expressed splice variants in five samples with high versus five with low levels of hypoxia-associated genes (Winter et al, 2007; Cancer Res 67:3441-9). The analysis identified a splice variant of LAMA3 (Laminin 3), LAMA3-A, known to be involved in tumour cell invasion and progression. The full-length transcript of the gene (LAMA3-B) did not appear to be hypoxia-associated. The results were confirmed using qualitative real time PCR. In a series of 59 prospectively-collected head and neck tumours (Winter et al, 2007; Cancer Res 67:3441-9), expression of LAMA3-A had prognostic significance whereas LAMA3-B did not. This work illustrates the potential for alternatively spliced transcripts to act as biomarkers of disease prognosis with improved specificity for particular tissues or conditions over assays which do not discriminate between splice variants.
2009-10-07 | GSE18300 | GEO
Project description:Changes in alternative splicing are associated with several pathological conditions, including cancer. Microarrays strategies, which allow for the characterization of thousands of alternative splice forms in a single test, can be applied to identify differential alternative splicing events. In this study, a novel splice array platform was developed, including the design of a high-density oligonucleotide array, a labeling procedure, and an algorithm to identify splice events. The array consists of exon probes and thermodynamically balanced junction probes. Suboptimal probes are tagged and considered in the final analysis. An unbiased labeling protocol was developed using random primers. The algorithm used to distinguish changes in expression from changes in splicing was calibrated using internal non-spliced control sequences. The performance of this splice array was first validated with artificial constructs for CDC6, VEGF, and PCBP4 isoforms. The platform was then applied to the analysis of differential splice forms for 8000 genes in lung cancer samples compared to matched normal lung tissue. The expression of lung cancer-associated splice isoforms was validated by RT-PCR. Overexpression of splice isoforms was identified for genes encoding CEACAM1, FHL-1, MLPH, and SUSD2. None of these splicing isoforms had been previously associated with lung cancer. In conclusion, this highly accurate methodology enables the detection of alternative splicing events in complex biological samples, providing a powerful tool to identify novel diagnostic and prognostic biomarkers for cancer and other pathologies.
2009-10-06 | GSE18346 | GEO
Project description:Purpose: The goal of this study was to use deep sequencing to identify all splice variants of Calcium/calmodulin-dependent kinase II (CaMKII) expressed in the human hippocampus. Methods: Transcripts of CaMKII-encoding genes (CAMK2A, CAMK2B, CAMK2G, and CAMK2D) were sub-amplified by PCR from total RNA extracted from human hippocampal tissue samples from 3 donors. Illumina sequencing libraries were constructed by PCR from these initial pools of amplicons and sequenced on an Illumina MiSeq instrument. Sequencing reads passing quality controls were clustered on the basis of sequence identity or near-identity. Consensus sequences of clusters were mapped with known exons of CaMKII genes to identify the splice variant represented by each cluster. Donor 1 replicate 2, Donor 2, and Donor 3 libraries from genes CAMK2B, CAMK2G, and CAMK2D were first sequenced on a MiSeq Nano flow cell, then re-pooled for read balancing and sequenced again of a full-size MiSeq flow cell. For each library, reads from Nano and full-size flow cells were combined for subsequent analysis. Results: We perfomed the first comprehensive survey of CaMKII transcripts expressed in individual tissue samples (human hippocampus). We detected a total of 79 splice variants of the four human CaMKIIs: CaMKIIα (3), CaMKIIβ (30), CaMKIIγ (24), and CaMKIIδ (22), across tissue samples from 3 donors. This represents the vast majority of possible in-frame CaMKII splice variants (Sloutsky and Stratton, European Journal of Neuroscience, 2020; https://doi.org/10.1111/ejn.14761).
2020-07-21 | GSE154030 | GEO
Project description:Alternative splicing is a mechanism in eukaryotes by which different forms of messenger RNAs (mRNAs) are generated from the same gene. Identification of alternative splice variants requires the identification of peptides specific for alternative splice forms. For this purpose, we generated a human database which contains only proteotypic tryptic peptides specific for alternative splice forms from Swiss-Prot entries. Using this database allows an easy access to the peptide sequences that matches the unique amino acid sequence of splice variants to MS data. Furthermore, we combined this database without isoform 1-specific peptides with human Swiss-Prot. This combined database can be used as a general database for searching of LC-MS data. LC-MS data derived from in-solution digests of two different cell lines (LNCaP, HeLa), and phosphoproteomics studies were analyzed using these two databases. Several non-isoform 1-specific peptides were found in both cell lines, some of them seemed to be cell line specific. Control and apoptotic phosphoproteomes from Jurkat T cells revealed several non-isoform 1-specific peptides and some of them showed clear quantitative differences between the two states.
2017-05-19 | PXD006026 | Pride
Project description:Aberrant splice variants are involved in the initiation and/or progression of glial brain tumors. We therefore set out to identify splice variants that are differentially expressed between histological subgroups of gliomas. Splice variants were identified using a novel platform that profiles the expression of virtually all known and predicted exons present in the human genome. Exon-level expression profiling was performed on 26 glioblastomas, 22 oligodendrogliomas and 6 control brain samples. Our results demonstrate that Human Exon arrays can identify subgroups of gliomas based on their histological appearance and genetic aberrations. We next used our expression data to identify differentially expressed splice variants. In two independent approaches, we identified 49 and up to 459 exons that are differentially spliced between glioblastomas and oligodendrogliomas a subset of which (47% and 33%) were confirmed by RT-PCR. In addition, exon-level expression profiling also identified >700 novel exons. Expression of ~67% of these candidate novel exons was confirmed by RT-PCR. Our results indicate that exon-level expression profiling can be used to molecularly classify brain tumor subgroups, can identify differentially regulated splice variants and can identify novel exons. The splice variants identified by exon-level expression profiling may help to detect the genetic changes that cause or maintain gliomas and may serve as novel treatment targets. Keywords: cell type comparison 6 adult non diseased brain, 26 glioblastomas, 21 oligodendrogliomas
2008-01-28 | E-GEOD-9385 | biostudies-arrayexpress
Project description:Knockin mice were created that contained a point mutation that elminated the requisite GT in the 5' donor site of each of the NCoRω or NCoRδ splice variants, thus preventing splicing at that site and forcing splicing of the reciprocal splice variant.
2020-09-11 | GSE157761 | GEO
Project description:Splice variants in Human and rhesus macaque KIR alleles.
| PRJEB27409 | ENA