Lariat mapping of a DBR1 CRISPR KO cell line
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA801289 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:We constructed a DBR1 knockout cell line (C22) using CRISPR in HEK293T cells. Through mapping of lariat reads, lariat levels in the DBR1 - samples are shown to increase dramatically (~20x) relative to wild type cells. Over 60% of this increase in lariat levels is abrogated upon rescue of DBR1 - cells with a DBR1 expression vector
2022-01-29 | GSE195469 | GEO
Project description:We used CRISPR in HEK293T cells to create two DBR1 knockout cell lines (C19 and C22). After high-throughput sequencing of total RNA extracted from these cells, we performed lariat read mapping using the method described in "Large-scale mapping of branchpoints in human pre-mRNA transcripts in vivo" (Taggart et al, 2012). We found lariats in the two DBR1- cell lines to be ~20-fold enriched relative to the levels observed in the HEK293T control samples.
2022-02-03 | GSE195586 | GEO
Project description:Using wild type HEK293T cells and our DBR1 CRISPR knockout cell line (C22), we investigated the effect of AQR knockdown on cellular lariat levels. Samples were taken after transfection with either one of two AQR-targeting siRNAs or a non-targeting control siRNA. After sequencing the samples, lariat mapping of the reads revealed that AQR knockdown increased the lariat recovery rate by ~50% relative to the level observed in the negative control samples.
2022-01-31 | GSE195668 | GEO
Project description:Lariat mapping of DBR1 KO and DBR1 KO+DBR1 addback cells
| PRJNA800759 | ENA
Project description:Lariat mapping of wild type and DBR1 KO cells after knockdown of AQR
| PRJNA801683 | ENA
Project description:The majority of genic transcription is intronic. Introns are removed by splicing as branched lariat RNAs which require rapid recycling. The branch site is recognized during splicing catalysis and later debranched by Dbr1 in the rate-limiting step of lariat turnover. Through generation of the first viable DBR1 knockout cell line, we find the predominantly nuclear Dbr1 enzyme to encode the sole debranching activity in human cells. Dbr1 preferentially debranches substrates that contain canonical U2 binding motifs, suggesting that branchsites discovered through sequencing do not necessarily represent those favored by the spliceosome. We find that Dbr1 also exhibits specificity for particular 5' splice site sequences. We identify Dbr1 interactors through co-immunoprecipitation mass spectroscopy. We present a mechanistic model for Dbr1 recruitment to the branchpoint through the intron-binding protein AQR. In addition to a 20-fold increase in lariats, Dbr1 depletion increases exon skipping. Using ADAR fusions to timestamp lariats, we demonstrate a defect in spliceosome recycling. In the absence of Dbr1, spliceosomal components remain associated with the lariat for a longer period of time. As splicing is co-transcriptional, slower recycling increases the likelihood that downstream exons will be available for exon skipping.
2023-06-26 | MSV000092263 | MassIVE
Project description:Lariat is formed by excised intron, in which the 5' splice site joints with the branchpoint (BP) during splicing. Although lariat RNAs are usually degraded by DBR1 (RNA debranching enzyme 1), recent findings in animals showed that many lariat RNAs were widely detected under physiological conditions. In contrast, the features of BPs and to what extent lariat RNAs accumulate naturally are largely unexplored in plants. Here, we analyzed 948 RNA sequencing datasets to document plant BPs and lariat RNAs on a genome-wide scale. In total, we identified 13872, 5199, 29582, and 13478 BPs in Arabidopsis, tomato, rice, and maize, respectively. Features of plant BPs are highly similar to those in yeast and human, in that BPs are adenine-preferred and flanked by uracil-enriched sequences. Intriguingly, ~20% of introns harbor multiple BPs, and BP usage is tissue-specific. Furthermore, 10580 lariat RNAs accumulate in wild type Arabidopsis plants, and most of these lariat RNAs originate from longer or retroelement-depleted introns, and the expression of these lariat RNAs significantly correlated with the incidence of back-splicing of parent exons. Collectively, our results provide the first comprehensive map of intron BPs and lariat RNAs in plants, and uncover a novel link between lariat turnover and splicing.
2019-04-17 | GSE117416 | GEO
Project description:Here we describe a lariat-sequencing approach, which offers high sensitivity for detecting splicing events, and its application to the unicellular fungus, Schizosaccharomyces pombe, an organism that shares many of the hallmarks of alternative splicing in mammalian systems but for which no previous examples of exon-skipping had been demonstrated. Over 200 previously unannotated splicing events were identified, including examples of regulated alternative splicing. Total RNA from ∆dbr1 S. pombe grown under 41 different conditions, pooled, then run under two-dimensional gel electrophoresis to separate linear from circular RNA. Circular RNA was excised and prepared as a single-end barcoded Illumina sequencing library.
2013-07-09 | E-GEOD-48594 | biostudies-arrayexpress
Project description:Both canonical and alternative splicing of RNAs is governed by intronic sequence elements and produces transient lariat structures fastened by branch-points within introns. To map precisely the location of branch-points on a genomic scale, we developed LaSSO (Lariat Sequence Site Origin), a data-driven algorithm which utilizes RNA-seq data. Using fission yeast cells lacking the debranching enzyme Dbr1, LaSSO not only accurately identified canonical splicing events, but also pinpointed novel, but rare, exon-skipping events, which may reflect aberrantly spliced transcripts. Compromised intron turnover perturbed gene regulation at multiple levels, including splicing and protein translation. Notably, Dbr1 function was also critical for the expression of mitochondrial genes, and for the processing of self-spliced mitochondrial introns. LaSSO showed better sensitivity and accuracy than algorithms used for computational branch-point prediction or for empirical branch-point determination. Even when applied to a human data set acquired in the presence of debranching activity, LaSSO identified both canonical and exon skipping branch-points. LaSSO thus provides an effective, accurate and unbiased approach for defining high-resolution maps of branch-site sequences and intronic elements on a genomic scale. LaSSO should be useful to validate introns and uncover branch-point sequences in any eukaryote, and it could be integrated to RNA-seq pipelines. Interrogation of the S. pombe transcriptome using rRNA depleted strand specific RNA sequencing (Illumina HiSeq 2000) in wild type and dbr1.M-NM-^T cultures. A total of 4 samples were analyzed: two biological repeates of wild-type strain and two biological repeats of dbr1.M-NM-^T
2014-03-18 | E-GEOD-50246 | biostudies-arrayexpress
Project description:Immortalised HaCaT keratinocytes were transduced with Cas9 and the CRISPR-KO v1.1 genome-wide gRNA library. The gRNA library was prepared from genomic DNA isolated 14 days post library transduction. gRNA representation will be compared to the original CRISPR-KO v1.1 library to reveal genes essential for HaCaT survival and growth.
| EGAS00001002714 | EGA