A new look at adenovirus splicing
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE54583 | GEO | 2014/03/25
REPOSITORIES: GEO
Similar Datasets
Project description:Adenovirus type 2 RNA splicing sites were mapped by using deep cDNA sequencing. The majority of the previously identified splice sites were detected. In addition, novel splicing sites were identified Total RNA obtained from four time stages of human primary lung fibroblast cells IMR-90 infected by adenovirus type 2 compared to the control mock-infected by adenovirus type 2.
2014-03-25 | E-GEOD-54583 | biostudies-arrayexpress
Project description:Adenovirus is a common human pathogen that relies on host cell processes for transcription and processing of viral RNA and protein production. Although adenoviral promoters, splice junctions, and cleavage and polyadenylation sites have been characterized using low-throughput biochemical techniques or short read cDNA-based sequencing, these technologies do not fully capture the complexity of the adenoviral transcriptome. By combining Illumina short-read and nanopore long-read direct RNA sequencing approaches, we mapped transcription start sites and cleavage and polyadenylation sites across the adenovirus genome. In addition to confirming the known canonical viral early and late RNA cassettes, our analysis of splice junctions within long RNA reads revealed an additional 35 novel viral transcripts. These RNAs include fourteen new splice junctions which lead to expression of canonical open reading frames (ORF), six novel ORF-containing transcripts, and fifteen transcripts encoding for messages that potentially alter protein functions through truncations or fusion of canonical ORFs. In addition, we also detect RNAs that bypass canonical cleavage sites and generate potential chimeric proteins by linking separate gene transcription units. Of these, an evolutionary conserved protein was detected containing the N-terminus of E4orf6 fused to the downstream DBP/E2A ORF. Loss of this novel protein, E4orf6/DBP, was associated with aberrant viral replication center morphology and poor viral spread. Our work highlights how long-read sequencing technologies can reveal further complexity within viral transcriptomes.
2022-08-30 | PXD034464 | Pride
Project description:All lentiviral vectors derived from HIV-1 have the major splice donor (SD1) in the 5’ leader region and splice acceptor 7 (SA7) within the env region. Splicing events decrease the amount of full-length RNA available for packaging into virions and could lead to packaging of genomes containing internal deletions. Because there are splice sites or splicing enhancer/silencer elements in both gag and env, we compared how deleting each region affected intracellular genomic RNA splicing in RNA isolated from transfected HEK293Tsa cells. Oxford Nanopore direct cDNA sequencing was used to characterize the splice variants because the long-read length allows full-length transcripts to be analyzed. We show that deleting 507 nt of env, including the SA7, decreased the number of splicing events per transcript and increased the proportion of unspliced genomic RNAs ~3-fold in the cell.
2021-01-30 | GSE165829 | GEO
Project description:Alternative splicing of pre-mRNAs increases the potential for regulation and complexity of gene expression. The exon junction complex (EJC) and its associated splicing factor RNPS1 were recently shown to suppress mis-splicing resulting from the usage of cryptic and reconstituted 5’ and 3’ splice sites in the vicinity of the EJC. Here, we aimed to further investigate the mechanisms underlying splicing regulation by RNPS1. A transcriptome-wide analysis identified hundreds of splice events affected by the knockdown (KD) of RNPS1 in HeLa cells. These included alternative splice site usage as well as intron retention, exon skipping and inclusion. However, only a fraction of these RNPS1-dependent splice events was fully or partially rescued by the expression of the RNPS1 RRM. These results indicated that another domain of RNPS1 is involved in the regulation of the majority of splicing events. Deletion experiments revealed that the N-terminus and S-domain, and in particular the C-terminus of RNPS1 strongly regulate these events. Several splicing factors, including SR proteins and U1 snRNP components, were strongly reduced in the interactome of RNPS1 lacking the C terminus. We conclude that RNPS1 interacts with many splicing factors to direct the assembly of EJC-dependent and-independent splicing complexes.
2022-05-31 | PXD027251 | Pride
Project description:RBFOX2 controls the splicing of a large number of transcripts implicated in cell differentiation and development. Parsing RNA-binding protein datasets, we uncover that RBFOX2 can interact with hnRNPC, hnRNPM and SRSF1 to regulate splicing of a broad range of splicing events using different sequence motifs and binding modes. Using immunoprecipitation, specific RBP knockdown, RNA-seq and splice-sensitive PCR, we show that RBFOX2 can target splice sites using three binding configurations: single, multiple or secondary modes. In the single binding mode RBFOX2 is recruited to its target splice sites through a single canonical binding motif, while in the multiple binding mode RBFOX2 binding sites include the adjacent binding of at least one other RNA binding protein partner. Finally, in the secondary binding mode RBFOX2 likely does not bind the RNA directly but is recruited to splice sites lacking its canonical binding motif through the binding of one of its protein partners. These dynamic modes bind distinct sets of transcripts at different positions and distances relative to alternative splice sites explaining the heterogeneity of RBFOX2 targets and splicing outcomes.
2021-06-23 | GSE140679 | GEO
Project description:RBM10 is an RNA binding protein that was identified as a component of spliceosome complex, suggesting its potential role in splicing regulation. However, the direct experimental evidence for this function has been lacking. Here we characterized in vivo RBM10-RNA interactions and investigated the role of RBM10 in splicing regulation at the global level. We observed significant RBM10-RNA interactions in the vicinity of splice sites and identified hundreds of splicing changes following perturbation of cellular RBM10 abundance. A RNA splicing map integrating the binding pattern and splicing profiles revealed a significant correlation between RBM10-enhanced exon skipping events and its binding close to the splicing sites of both upstream and downstream introns. Furthermore, we demonstrated the splicing defects in a patient carrying a RBM10 mutation. Overall, our data provided insights into the mechanistic model of RBM10-mediated splicing regulation and established genomic resources for future studies on its function in different pathophysiological contexts. We sequenced the mRNA of HEK293 cells and LCL cells, and we determined the RBM10 binding sites using PARCLIP in HEK293 cells. In total we sequenced four mRNA-Seq libraries for KD and two for OE in HEK293 cells; for each of these libraries, we also sequenced one control library. We also sequenced the mRNA of one patient LCL and two normal LCL libraries. Two replicates of PARCLIP sequencing were perfomed.
2013-09-03 | E-GEOD-44976 | biostudies-arrayexpress
Project description:Gene splicing requires three basal genetic elements; the 3M-bM-^@M-^Y and 5M-bM-^@M-^Y splice sites and the branchpoint to which the 5M-bM-^@M-^Y intron termini is ligated to form a closed lariat during the splicing reaction. The 5M-bM-^@M-^Y and 3M-bM-^@M-^Y splice sites that define exon boundaries have been widely identified, revealing pervasive transcription and splicing of human genes. However, the locations of the third requisite element, the branchpoint, are still largely unknown. Here we employ two complementary approaches, targeted RNA sequencing and exoribonuclease digestion, to distil sequenced reads that traverse the lariat junction and, via non-conventional alignment, locate human branchpoint nucleotides. Alignments identify 88,748 branchpoints that correspond to 20% of known introns, with 76% supported by diagnostic sequence mismatch errors. This affords a first genome-wide analysis of branchpoints, describing their distribution, selection, and the existence of a diverse array of overlapping sequence motifs with distinct usage, evolutionary histories, and co-variation with distal splicing elements. The overlap of branchpoints with noncoding human genetic variation also indicates a notable contribution to disease. This annotation and analysis incorporates branchpoints into transcriptomic research and reflects a core role for this element in the regulatory code that governs gene splicing and expression. CaptureSeq identification of branchpoint nucleotides
2014-10-01 | E-GEOD-53326 | biostudies-arrayexpress
Project description:Gene splicing requires three basal genetic elements; the 3M-bM-^@M-^Y and 5M-bM-^@M-^Y splice sites and the branchpoint to which the 5M-bM-^@M-^Y intron termini is ligated to form a closed lariat during the splicing reaction. The 5M-bM-^@M-^Y and 3M-bM-^@M-^Y splice sites that define exon boundaries have been widely identified, revealing pervasive transcription and splicing of human genes. However, the locations of the third requisite element, the branchpoint, are still largely unknown. Here we employ two complementary approaches, targeted RNA sequencing and exoribonuclease digestion, to distil sequenced reads that traverse the lariat junction and, via non-conventional alignment, locate human branchpoint nucleotides. Alignments identify 88,748 branchpoints that correspond to 20% of known introns, with 76% supported by diagnostic sequence mismatch errors. This affords a first genome-wide analysis of branchpoints, describing their distribution, selection, and the existence of a diverse array of overlapping sequence motifs with distinct usage, evolutionary histories, and co-variation with distal splicing elements. The overlap of branchpoints with noncoding human genetic variation also indicates a notable contribution to disease. This annotation and analysis incorporates branchpoints into transcriptomic research and reflects a core role for this element in the regulatory code that governs gene splicing and expression. RNaseR validation of branchpoint nucleotides
2014-10-01 | E-GEOD-53327 | biostudies-arrayexpress
Project description:Analysis of splicing defects in Schizosaccharomyces pombe upon chemical genetic inhibition of splicing kinases dsk1, lkh1, and prp4, as well as alanine-mutation of phosphorylated residues in the splicing factors bpb1, prp2, rsd1, srp1, srp2, usp101, usp103, sum3, prp22, cdc5, and cwf22. This study shows the splicing kinase dsk1 modulates splicing efficiency of introns with non-consensus splice sites, likely through phosphorylation of bpb1. Modulation of splicing efficiency of transcripts through kinase signaling pathways may afford the necessary flexibility to tune the gene expression profile in response to environmental and developmental cues. Experiments were conducted as direct two-color designs with 2-3 biological replicates per genotype pairing. Raw microarray data was normalized with loess normalization using the R package limma. Log2-fold changes (perturbation over reference) are reported. Each splicing event on the custom-designed splicing microarray was monitored with an exon probe reading out mRNA changes, an intron probe for unspliced pre-mRNA, and a splice junction probe spanning the junction between two spliced exons. For the analysis of the splicing efficiency for a given intron, a score was calculated as exon*intron/junction.
2015-07-13 | E-GEOD-62752 | biostudies-arrayexpress
Project description:Alternative splicing diversifies mRNA transcripts in human cells. While the spliceosome pairs exons with a high degree of accuracy, the rates of rare aberrant and non-canonical pre-mRNA splicing have not been evaluated at the nucleotide level to determine the quantity and identity of these events across splice junctions. Using ultra-deep sequencing the frequency of aberrant and non-canonical splicing events for three splice junctions flanking exon 7 of SMN1 were determined at single nucleotide resolution. After correction for background noise introduced by PCR amplification and sequencing steps, pre-mRNA splicing was shown to maintain a low overall rate of aberrant and non-canonically spliced events. Several previously unannotated splicing events across 3 exon|intron junctions in SMN1 were identified. Mutations within SMN exon 7 were shown to affect splicing fidelity by modulating RNA secondary structures, by altering the binding site of regulatory proteins and by changing the 5’ splice site strength. Mutations also create a truncated SMN1 exon 7 through the introduction of a de novo non-canonical 5’ splice site. The results from the ultra-deep sequencing approach highlight the impressive fidelity of pre-mRNA splicing and demonstrate that the immediate sequence context around splice sites is the main driving force behind non-canonical splice site pairing.
2019-09-24 | GSE137883 | GEO