Deep surveying of alternative splicing complexity in the human transcriptome by high-throughput sequencing
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE13652 | GEO | 2008/11/19
SECONDARY ACCESSION(S): PRJNA110203
REPOSITORIES: GEO
Similar Datasets
Project description:We carried out the first analysis of alternative splicing complexity in human tissues using mRNA-Seq data. New splice junctions were detected in 20% of multiexon genes, many of which are tissue specific. By combining mRNA-Seq and EST-cDNA sequence data, we estimate that transcripts from 95% of multiexon genes undergo alternative splicing and that there are 100,000 intermediate- to high-abundance alternative splicing events in major human tissues. From a comparison with quantitative alternative splicing microarray profiling data, we also show that mRNA-Seq data provide reliable measurements for exon inclusion levels. Keywords: mRNA expression 32-nucleotide sequence reads from six human tissues including brain, cerebral cortex, heart, liver, lung and skeletal muscle.
2008-11-19 | E-GEOD-13652 | biostudies-arrayexpress
Project description:Alternative splicing produces multiple, distinct mRNA transcripts from the same gene locus. To explore tissue-type specific gene expression and alternative splicing, we generated mRNA-Seq data from pupal tissues dissected from Drosophila. This allowed us to compare expression between dissected, highly enriched brain and indirect flight muscle (IFM) samples as well as whole legs. Bioinformatic analysis allowed us to characterize tissue-specific differences in gene expression as well as alternative splicing among the three tissues, as well as to identify a multitude of novel splicing events that are not currently contained in the Drosophila annotation. This suggests that tissue or cell-type specific sequencing at multiple timepoints during the fly life cycle will help extend existing annotations, and novel splice junction discovery is an important consideration in mRNA-Seq data analysis.
2022-01-25 | GSE194199 | GEO
Project description:Establishing the functional roles of genetic variants remains a significant challenge in the post-genomic era. Here, we present a method, allele-specific alternative mRNA processing (ASARP), to identify genetically influenced mRNA processing events using transcriptome sequencing (RNA-Seq) data. The method examines RNA-Seq data at both single nucleotide and whole-gene/isoform levels to identify allele-specific expression (ASE) and existence of allele-specific regulation of mRNA processing. We applied the methods to data obtained from the human glioblastoma cell line U87MG and primary breast cancer tissues and found that 26M-bM-^@M-^S45% of all genes with sufficient read coverage demonstrated ASE, with significant overlap between the two cell types. Our methods predicted potential mechanisms underlying ASE due to regulations affecting either whole-gene-level expression or alternative mRNA processing, including alternative splicing, alternative polyadenylation and alternative transcriptional initiation. Allele-specific alternative splicing and alternative polyadenylation may explain ASE in hundreds of genes in each cell type. Reporter studies following these predictions identified the causal single nucleotide variants (SNVs) for several allele-specific alternative splicing events. Finally, many genes identified in our study were also reported as disease/phenotype-associated genes in genome-wide association studies. Future applications of our approach may provide ample insights for a better understanding of the genetic basis of gene regulation underlying phenotypic diversity and disease mechanisms. Examine allele-specific gene expression and alternative RNA processing in U87MG cell line
2012-03-29 | E-GEOD-29738 | biostudies-arrayexpress
Project description:Thousands of human genes contain introns ending in NAGNAG motifs (N any nucleotide), where both NAGs can function as 3' splice sites, yielding isoforms differing by inclusion/exclusion of just three bases. However, the functional importance of NAGNAG alternative splicing is highly controversial. Using very deep RNA-Seq data from sixteen human and eight mouse tissues, we found that approximately half of alternatively spliced NAGNAGs undergo tissue-specific regulation and that regulated events have been selectively retained: alternative splicing of strongly tissue-specific NAGNAGs was ten times as likely to be conserved between species as for non-tissue-specific events. Further, alternative splicing of human NAGNAGs was associated with an order of magnitude increase in the frequency of exon length changes at orthologous mouse/rat exon boundaries, suggesting that NAGNAGs accelerate exon evolution. Together, our analyses show that NAGNAG alternative splicing constitutes a major generator of tissue-specific proteome diversity and accelerates evolution of proteins at exon-exon boundaries. mRNA-Seq of sixteen human and eight mouse tissues. Supplementary files: human.nagnag.junctions.gff and mouse.nagnag.junctions.gff are the annotation files (in GFF3 format) corresponding to the 'bwtout' mapped reads files linked to the Sample records. Raw data files provided for Samples GSM742937-GSM742952 only.
2012-01-05 | E-GEOD-30017 | biostudies-arrayexpress
Project description:Huntingtonâs disease (HD) is an autosomal dominant neurodegenerative disorder caused by a CAG expansion in the gene encoding Huntingtin (HTT). Transcriptome dysregulation is a major feature of HD pathogenesis, as revealed by a large body of work on gene expression profiling of tissues from human HD patients and mouse models. These studies were primarily focused on transcriptional changes affecting steady-state overall gene expression levels using microarray based approaches. A major missing component however has been the study of transcriptome changes at the post-transcriptional level, such as alternative splicing. Alternative splicing is a critical mechanism for expanding regulatory and functional diversity from a limited number of genes, and is particularly complex in the mammalian brain. Here we carried out a deep RNA-seq analysis of 7 human HD brains and 7 controls to systematically discover aberrant alternative splicing events and characterize potential associated splicing factors in HD. We identified 593 differential alternative splicing events between HD and control brains. Using an expanded panel of 54 brain tissues from patients and controls, we also identified 9 splicing factors exhibiting significantly altered expression levels in HD patient brains. Moreover, follow-up molecular analyses of one splicing factor PTBP1 revealed its impact on disease-associated splicing patterns in HD. Collectively, our data provide genomic evidence for widespread splicing dysregulation in HD brains, and suggest the role of aberrant alternative splicing in the pathogenesis of HD RNA-seq analysis of the BA4 motor cortex of 7 control and 7 Huntington's disease patients. 1.5 ug of total RNA was used for RNA-seq library preparation using the TruSeq⢠Stranded mRNA LT Sample Prep Kit (Illumina). 100x2 bp paired-end RNA-seq reads were generated on a HiSeq 2000 sequencer.
2016-06-14 | E-GEOD-79666 | biostudies-arrayexpress
Project description:Co-transcriptional processing of nascent transcripts is coupled with transcription through the carboxy-terminal domain (CTD) of RNA polymerase II (RNAPII). The mRNA modification N6-methyladenosine (m6A) occurs co-transcriptionally and impacts pre-mRNA processing. How alternative splicing of pre-mRNA is co-transcriptionally regulated in an m6A-dependent manner is not well understood. Furthermore, splicing regulation through RNAPII pausing has been frequently suggested but the underlying control mechanism remains unclear. Here, we show that the m6A reader protein hnRNPG directly binds to the phosphorylated CTD of RNAPII using Arg-Gly-Gly (RGG) motifs in its low-complexity region. This RGG-phospho-CTD interaction and nascent RNA binding by hnRNPG enables its co-transcriptional association with RNAPII, resulting in transcriptome-wide regulation of alternative splicing and transcript abundance. m6A sites near exon splice sites in nascent mRNA further modulate hnRNPG binding and exon splicing. Exon inclusion is associated with RNAPII pausing downstream of the m6A site. Our results reveal an integrated nuclear mechanism of m6A-mediated gene regulation, in which an m6A reader protein regulates gene expression by using RGG motifs to co-transcriptionally interact with both RNAPII and m6A-modified nascent pre-mRNA, while the interplay between hnRNPG binding and RNAPII pausing modulates alternative splicing regulation.
2019-09-05 | GSE114311 | GEO
Project description:Abstract: Alternative splicing (AS) plays a major role in the generation of proteomic diversity and in gene regulation. However, the role of the basal splicing machinery in regulating AS remains poorly understood. Here we show that the core snRNP protein SmB/B’ self-regulates its expression by promoting the inclusion of a highly-conserved alternative exon in its own pre-mRNA that targets the spliced transcript for nonsense-mediated mRNA decay (NMD). Depletion of SmB/B’ in human cells results in reduced levels of snRNPs and in a striking reduction in the inclusion levels of hundreds of alternative exons, with comparatively few effects on constitutive exon splicing levels. The affected alternative exons are enriched in genes encoding RNA processing and other RNA binding factors, and a subset of these exons also regulate gene expression by activating NMD. Our results thus demonstrate a role for the core spliceosomal machinery in controlling an exon network that appears to modulate the levels of many RNA processing factors. HeLa cells were transfected with a control non-targeting siRNA pool (siNT), or with siRNA pools designed to knockdown SmB/B' or SRSF1 (also known as SF2/ASF/SFRS1). Sequence reads were aligned to exon-exon junction sequences in a database of EST/cDNA-mined cassette-type alternative splicing events. Processed data files (.bed and .txt) provided as supplementary files on the Series record. Processed data file build information: hg18.
2011-02-01 | E-GEOD-26463 | biostudies-arrayexpress
Project description:Mitosis deregulation is a key event during carcinogenesis. Alternative splicing spectrum alteration plays a critical role during mitosis shift. However, the molecules responsible for dysregulated alternative splicing driving carcinogenetic mitosis remain poorly defined. Here, we demonstrate that cancer metastasis-associated antigen 1 (MTA1), a well-known oncogenic chromatin modifier, broadly interacts and co-expresses with RBPs across cancers, contributes to cancerous mitosis-related alternative splicing. Using developed fCLIP-seq technology, we show that MTA1 binds abundant transcripts, preferentially at splicing-responsible motifs, influencing both the abundance and alternative splicing (AS) of target transcripts. MTA1 is cytoplasmic and extrachromosomal at mitosis. Through the RNA-association activity, MTA1 regulates the mRNA level and guides the AS of a serious of mitosis regulators to control the mitosis. MTA1 deletion abrogated the dynamic AS switches of variants for ATRX and MYBL2 at mitotic stage, which are relevant to mitosis and tumorigenesis. MTA1 dysfunction causes a defective mitotic arrest, leading to aberrant chromosome segregation, and resultantly chromosomal instability (CIN) in cancer cells and tissues, which eventually contributes to tumorigenesis. Currently, little is known about the RNA splicing during mitosis, here, we present MTA1 as a pivotal RNA-binding protein, functioning to orchestrate the dynamic splicing of mitosis regulators linked to mitosis control in tumorigenesis.
2020-03-30 | PXD018242 | iProX