HDBR1 OVEREXPRESSED CALU6 AND 293T CELLS VS. CONTROL CELLS
Ontology highlight
ABSTRACT:
INSTRUMENT(S): Illumina HiScanSQ
ORGANISM(S): Homo sapiens
SUBMITTER: BING HAN
PROVIDER: E-MTAB-5347 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
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2019-04-17 | GSE117416 | GEO
Project description:Introns in pre-mRNAs must be spliced out prior to their translation. During splicing, introns are removed in the form of a lariat, in which the 5' end is linked to the 2' hydroxyl of an internal adenosine. Lariat degradation is initiated by an 2'-5' phosphodiester-specific RNA endonuclease which debranches these lariat RNAs to linear form. Deletion of the debranching enzyme is yeast results in the accumulation of lariat introns. We used this accumulation to identify spliced lariat introns on a genome-wide scale in S. cerevisiae using tiling microarrays. Keywords: two sample comparison, 3 biological replicates
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Project description:Transciptional profiling of Calu6 tumors comparing 4 pooled untreated tumors to 5-azacytodine or 5-azacytodine + MS-275 (combined therapy) treated tumors Three-condition experiment, untreated vs. 5-Azacytodine tumors, and untreated vs. 5-azacytodine + MS-275 tumors: 4 pooled untreated tumors; 4 5-Azacytodine treated, 4 5-Azacytodine + MS-275 treated. Study used a loop design with dye-swap.
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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
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