Single-cell RNA-seq of peripheral blood links cell-type-specific regulation of splicing to autoimmune and inflammatory diseases [scRNAseq_JP_RIK]
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE280974 | GEO | 2024/12/05
REPOSITORIES: GEO
Similar Datasets
Project description:Alternative splicing is pivotal in the genetics of complex traits, but a detailed understanding requires relevant cell types from diverse genetic ancestries. Here, we described cell-type-specific, sex-biased, and ancestry-biased alternative splicing in ~1M peripheral blood mononuclear cells from 474 healthy donors from the Asian Immune Diversity Atlas. We identified widespread sex- and ancestry-biased differentially splicing, most of which are cell-type-specific. We identified 11,577 independent cis-sQTLs, 607 trans-sQTLs, and 107 dynamic sQTLs. Colocalization between cis-eQTL and trans-sQTL revealed a cell-type-specific regulatory relationship between hnRNPLL and PTPRC. We observed a strong enrichment of cis-sQTL effects in autoimmune and inflammatory disease heritability. Specifically, we functionally validated an Asian-specific sQTL disrupting the 5’ splice site of TCHP exon four to putatively modulate the risk of Graves’ disease in East Asian populations. Our work highlights the critical impact of ancestral diversity and provides a roadmap to dissect splicing mechanisms in complex diseases at single-cell resolution.
2024-12-05 | GSE281106 | GEO
Project description:Coronary artery disease (CAD) is the leading cause of death worldwide. A recent meta-analysis of genome-wide association studies (GWAS) identified 175 loci associated with CAD. The majority of these loci are in non-coding regions and are predicted to regulate gene expression. We hypothesized that a subset of the CAD GWAS loci was associated with the regulation of transcription in vascular smooth muscle cells (SMCs), which play critical roles in the development of CAD. We measured gene expression in SMCs isolated from the ascending aortas of 151 ethnically diverse heart transplant donors in quiescent or proliferative conditions and calculated the association of their expression and splicing with ~6.3 million imputed single nucleotide polymorphism (SNP) markers across the genome. We identified 4,910 expression and 4,412 splice quantitative trait loci (sQTL) that represent regions of the genome associated with transcript abundance and splicing. 3,660 of the expression quantitative trait loci (eQTL) had not been observed in the publicly available Genotype-Tissue Expression dataset. Further, 29 and 880 of the eQTLs were SMC- and sex-specific, respectively. To identify the effector transcripts regulated by the CAD GWAS loci, we used four distinct colocalization approaches and identified 84 eQTL and 164 sQTLs that colocalized with CAD loci, suggesting a more significant role for the genetic regulation of mRNA splicing as a molecular mechanism for CAD genetic risk. 20% and 35% of the eQTLs were unique to quiescent or proliferative SMCs, respectively. Two of the CAD loci colocolized with SMC eQTL showed sex-specific (AL160313.1 and TERF2IP) and one of the loci colocalized with SMC-specific eQTLs (ALKBH8). 27% and 37% of the sQTLs were unique to quiescent or proliferative SMCs, respectively. The most significantly associated CAD locus, 9p21, was an sQTL for the long non-coding RNA CDKN2B-AS1, also known as ANRIL, in proliferative SMCs. Collectively, these results provide evidence for the molecular mechanisms of genetic susceptibility to CAD in vascular smooth muscle cells.'
2022-10-03 | GSE198544 | GEO
Project description:Coronary artery disease (CAD) is the leading cause of death worldwide. A recent meta-analysis of genome-wide association studies (GWAS) identified 175 loci associated with CAD. The majority of these loci are in non-coding regions and are predicted to regulate gene expression. We hypothesized that a subset of the CAD GWAS loci was associated with the regulation of transcription in vascular smooth muscle cells (SMCs), which play critical roles in the development of CAD. We measured gene expression in SMCs isolated from the ascending aortas of 151 ethnically diverse heart transplant donors in quiescent or proliferative conditions and calculated the association of their expression and splicing with ~6.3 million imputed single nucleotide polymorphism (SNP) markers across the genome. We identified 4,910 expression and 4,412 splice quantitative trait loci (sQTL) that represent regions of the genome associated with transcript abundance and splicing. 3,660 of the expression quantitative trait loci (eQTL) had not been observed in the publicly available Genotype-Tissue Expression dataset. Further, 29 and 880 of the eQTLs were SMC- and sex-specific, respectively. To identify the effector transcripts regulated by the CAD GWAS loci, we used four distinct colocalization approaches and identified 84 eQTL and 164 sQTLs that colocalized with CAD loci, suggesting a more significant role for the genetic regulation of mRNA splicing as a molecular mechanism for CAD genetic risk. 20% and 35% of the eQTLs were unique to quiescent or proliferative SMCs, respectively. Two of the CAD loci colocolized with SMC eQTL showed sex-specific (AL160313.1 and TERF2IP) and one of the loci colocalized with SMC-specific eQTLs (ALKBH8). 27% and 37% of the sQTLs were unique to quiescent or proliferative SMCs, respectively. The most significantly associated CAD locus, 9p21, was an sQTL for the long non-coding RNA CDKN2B-AS1, also known as ANRIL, in proliferative SMCs. Collectively, these results provide evidence for the molecular mechanisms of genetic susceptibility to CAD in vascular smooth muscle cells.'
2022-01-20 | GSE193817 | GEO
Project description:Genome-wide association studies (GWASs) have revealed thousands of associations in many complex traits and diseases. Previous studies suggest that a subset of associations are due to alterations in splicing; however, interpreting the effects of splicing on protein isoforms is hindered by limitations in defining full-length transcript isoforms using short-read RNA-seq data. Long-read RNA-seq represents a powerful approach to define and quantify transcript isoforms. In this study, we developed a novel approach that integrates information from GWAS, splicing QTL (sQTL), and PacBio long-read RNA-seq in a disease relevant model to infer the effects of sQTL on the ultimate protein isoform products they encode. Such information enables identification of genes potentially responsible for GWAS associations. As a proof-of-concept, we generated deep coverage (N=~22 million full-length reads) PacBio long-read RNAseq data on human fetal osteoblasts (hFOBs), a cell-line of relevance to the regulation of bone mineral density (BMD). We identified 68,326 protein-coding isoforms, including 17,375 (25%) which were novel. Next, we used Bayesian colocalization to identify 1,863 sQTLs from the Genotype-Tissue Expression (GTEx) project in 732 protein-coding genes which colocalized with BMD associations (H4PP > 0.75). A total of 836 junctions with colocalizing sQTLs in 459 (of the 732) genes were expressed in hFOB long-read RNA-seq data. With these data, we formulated hypotheses regarding the potential mechanism of action of each sQTL. For example, we identified 7 junctions with colocalizing sQTLs (maximum H4PP = 0.98-0.99) in TPM2 for splice junctions between two nearly mutually exclusive exons, and two different transcript termination sites, making it impossible to interpret without long-read RNA-seq data. siRNA mediated knockdown in hFOBs showed two TPM2 isoforms with opposing effects on mineralization. Our results suggest that splicing is a major mechanism underlying GWAS associations and long-read proteogenomics data is critical to precisely define the protein isoforms that are produced from splicing alterations.
2023-03-01 | GSE224588 | GEO
Project description:Background: Substantial progress has been made in the identification of sequence elements that control mRNA splicing and the genetic variants in these elements that alter mRNA splicing (referred to as splicing quantitative trait loci -- sQTLs). Genetic variants that affect mRNA splicing in trans are harder to identify because their effects can be more subtle and diffuse, and the variants are not co-located with their targets. We carried out a transcriptome-wide analysis of the effects of a mutation in a ubiquitous splicing factor that causes retinitis pigmentosa (RP) on mRNA splicing, using exon microarrays. Results: Exon microarray data was generated from whole blood samples obtained from four individuals with a mutation in the splicing factor PRPF8 and four sibling controls. Although the mutation has no known phenotype in blood, there was evidence of widespread differences in splicing between cases and controls (affecting between 10\% and 25\% of exons). Most probesets with significantly different inclusion (defined as the expression intensity of the exon divided by the expression of the corresponding transcript) between cases and controls had higher inclusion in cases and corresponded to exons that were shorter than average, AT-rich, located towards the 5' end of the gene and flanked by long introns. Introns flanking affected probesets were particularly depleted for the shortest category of introns, associated with splicing via intron definition. Conclusions: Our results show that a mutation in a splicing factor, with a phenotype that is restricted to retinal tissue, acts as a trans-sQTL cluster in whole blood samples. Characteristics of the affected exons suggest that they are spliced co-transcriptionally and via exon definition. Eight samples consisting of four sibling pairs were analysed. One individual in each pair harboured an RP-causing mutation on the PRPF8 gene (cases). Unaffected siblings were used as controls.
2012-12-25 | E-GEOD-43134 | biostudies-arrayexpress
Project description:Background: Substantial progress has been made in the identification of sequence elements that control mRNA splicing and the genetic variants in these elements that alter mRNA splicing (referred to as splicing quantitative trait loci -- sQTLs). Genetic variants that affect mRNA splicing in trans are harder to identify because their effects can be more subtle and diffuse, and the variants are not co-located with their targets. We carried out a transcriptome-wide analysis of the effects of a mutation in a ubiquitous splicing factor that causes retinitis pigmentosa (RP) on mRNA splicing, using exon microarrays. Results: Exon microarray data was generated from whole blood samples obtained from four individuals with a mutation in the splicing factor PRPF8 and four sibling controls. Although the mutation has no known phenotype in blood, there was evidence of widespread differences in splicing between cases and controls (affecting between 10\% and 25\% of exons). Most probesets with significantly different inclusion (defined as the expression intensity of the exon divided by the expression of the corresponding transcript) between cases and controls had higher inclusion in cases and corresponded to exons that were shorter than average, AT-rich, located towards the 5' end of the gene and flanked by long introns. Introns flanking affected probesets were particularly depleted for the shortest category of introns, associated with splicing via intron definition. Conclusions: Our results show that a mutation in a splicing factor, with a phenotype that is restricted to retinal tissue, acts as a trans-sQTL cluster in whole blood samples. Characteristics of the affected exons suggest that they are spliced co-transcriptionally and via exon definition.
2012-12-25 | GSE43134 | GEO
Project description:Regulation of mRNA splicing is a critical and tightly regulated cellular function, underlying the majority of proteomic diversity in our genomes. While disruption of this process is common in disease, the basic genetic complexity of alternative splicing in vivo remains poorly understood. To delineate the splicing landscape in disease, we used an integrative genomics approach and combined both genome and exon level transcriptome data in two somatic tissues (cerebella and peripheral ganglia) from a transgenic mouse model of neuroblastoma, a tumor that arises from peripheral ganglia. These data identify splicing quantitative trait loci (sQTL) that modulate differential splicing across the genome. Among these, an sQTL at FUBP1 revealed a splicing event that modulated levels of the MYC oncoprotein in human neuroblastoma-derived cell lines and correlated with outcome in neuroblastoma. Through this unbiased sQTL analysis, we also define de novo splicing motifs that serve as sites for recurrent mutations in cancer and lead to functional changes in exon expression, enhancing our understanding of the cancer genome. Exon expression from Superior Cervical Ganglia and Cerebellum from 102 backcrossed mice (TH-MYCN, FVB/NJ and 129/SvJ) were correlated with 349 genotyping markers to identify putative sQTL The mice were the N1 generation of a backcross between TH-MYCN (FVB/NJ background) and wild-type 129/SvJ: TH-MYCN (FVB/NJ) + 129/SvJ -> F1 (TH-MYCN FVB/NJ,129/SVJ) F1 (TH-MYCN FVB/NJ,129/SVJ) + 129/SvJ -> N1
2015-04-03 | E-GEOD-55248 | biostudies-arrayexpress
Project description:The diversity of peptides displayed by class I HLA plays an essential role in T cell immunity. The peptide repertoire is extended by various post-translational modifications, including cis-splicing of peptides from the same protein. Here, we have applied a novel bioinformatic workflow and demonstrate that spliced-peptides are also generated through trans-splicing (fusion of peptide segments from distinct antigens) and their abundance challenges current models of proteasomal-splicing that predict cis-splicing as the most probable outcome. These trans-spliced peptides display canonical HLA binding motif sequence features. These results highlight the unanticipated diversity of the immunopeptidome and have important implications for autoimmunity, vaccine design and immunotherapy.
2021-12-06 | PXD017922 | Pride
Project description:The diversity of peptides displayed by class I HLA plays an essential role in T cell immunity. The peptide repertoire is extended by various post-translational modifications, including cis-splicing of peptides from the same protein. Here, we have applied a novel bioinformatic workflow and demonstrate that spliced-peptides are also generated through trans-splicing (fusion of peptide segments from distinct antigens) and their abundance challenges current models of proteasomal-splicing that predict cis-splicing as the most probable outcome. These trans-spliced peptides display canonical HLA binding motif sequence features. These results highlight the unanticipated diversity of the immunopeptidome and have important implications for autoimmunity, vaccine design and immunotherapy.
2018-10-16 | PXD009660 | Pride
Project description:Individuals from different populations vary considerably in their susceptibility to immune-related diseases. To understand how genetic variation and natural selection contribute to these differences, we tested for the effects of African versus European ancestry on the transcriptional response of primary macrophages to live bacterial pathogens. 12% of macrophage-expressed genes show ancestry-associated differences in the gene regulatory response to infection, and African ancestry specifically predicts a stronger inflammatory response and reduced intracellular bacterial growth. A large proportion of these differences are under genetic control: for 569 genes, more than 75% of ancestry effects on the immune response can be explained by a single cis- or trans-acting eQTL. Finally, we show that genetic effects on the immune response are strongly enriched for recent, population-specific signatures of adaptation. Together, our results demonstrate how historical selective events continue to shape human phenotypic diversity today, including for traits that are central to coping with infection. Transcriptomic profiles of 503 infected (Listeria and Salmonella) and non-infected samples at 2hr time point.
2016-09-06 | E-GEOD-81046 | biostudies-arrayexpress