Project description:tau circular RNAs undergo Adenosine to inosine editing, which promotes their translation. To map editing sites,we cotransfected expression constructs for tau 7->12 and 10->12 circRNAs with expression constructs for GFP, ADAR1, ADAR2 and ADAR3 in HEK293 cells. RNA from these transfected cells was isolated and A>I editing was identified by A>G changes in the cDNA.
Project description:A validation experiment performed on HEK293 cell lines after genome editing. The design contains three duplicate runs consisted of: HEK293 wild type cell line HEK293 with MIR484 gene knockdown using CRISPR-Cas9 HEK293 with MIR185 gene knockout using CRISPR-Cas9
Project description:Double-stranded RNA (dsRNA) can enter different pathways in mammalian cells, including sequence-specific RNA interference, sequence-independent interferon response and editing by adenosine deaminases. To assess the potential of expressed dsRNA to induce interferon stimulated genes in somatic cells, we performed microarray analysis of HEK293 and HeLa cells transfected with a MosIR plasmid expressing an mRNA with a long inverted repeat structure in its 3’UTR (MosIR) or with a parental MosIR plasmid (without inverted repeat) as a control. Clustering analysis based on differentially expressed genes suggested that there was no common transcriptome signature in cells expressing dsRNA. Overall, the number of genes with altered expression upon transfection of the MosIR plasmid was rather small and only 19 probe sets, corresponding to 17 genes, were changed more than two-fold in both cell lines. Total RNA from cultured HEK293 or HeLa cells was used in each sample. Two independent biological replicates were analyzed for each condition.
Project description:Double-stranded RNA (dsRNA) can enter different pathways in mammalian cells, including sequence-specific RNA interference, sequence-independent interferon response and editing by adenosine deaminases. To assess the potential of expressed dsRNA to induce interferon stimulated genes in somatic cells, we performed microarray analysis of HEK293 and HeLa cells transfected with a MosIR plasmid expressing an mRNA with a long inverted repeat structure in its 3’UTR (MosIR) or with a parental MosIR plasmid (without inverted repeat) as a control. Clustering analysis based on differentially expressed genes suggested that there was no common transcriptome signature in cells expressing dsRNA. Overall, the number of genes with altered expression upon transfection of the MosIR plasmid was rather small and only 19 probe sets, corresponding to 17 genes, were changed more than two-fold in both cell lines.
Project description:To validate role of REST (RE-1 silencing transcription factor) in glioblastoma (GBM) growth, we used CRISPR/Cas9 gene editing to generate REST-null single-cell clonal lines from GBM cell line (T98G) and non-neural HEK293 cells. We then performed gene expression profiling using data obtained from Tag-Seq of 8 cell lines: T98G CRISRP Control and 4 T98G REST-KO clones (C10, F7, G2, D4); HEK293 CRISPR Control and 2 HEK293 REST-KO clones (D10, E6).
Project description:Alu element is a major contributor to lineage-specific new exons in the primate and human genomes. Recent studies indicate that some Alu exons have high transcript inclusion levels or tissue-specific splicing profiles, and may play important regulatory roles in modulating mRNA degradation or translational efficiency. However, the contribution of Alu exons to the human proteome remains unclear and controversial. The prevailing view is that exons derived from young repetitive elements (such as Alu) are restricted to regulatory functions but do not have adequate evolutionary time to be incorporated into stable, functional proteins. In this work, we adopt a proteotranscriptomics approach to systematically assess the contribution of Alu exons to the human proteome. Using RNA sequencing, ribosome profiling, and mass spectrometry data of diverse human tissues and cell lines, we provide evidence for the translational activities of Alu exons and the presence of Alu exon derived peptides in human proteins. These Alu exon peptides represent species-specific protein differences between primates and other mammals, and in certain instances even between humans and closely related nonhuman primates. In the RNA editing enzyme ADARB1, which contains an Alu exon peptide in its catalytic domain, RNA editing analyses of RNA-sequencing data demonstrate that both the Alu exon skipping and inclusion isoforms encode active RNA editing enzymes, while the Alu exon peptide may fine tune the editing activities of the ADARB1 protein products . Together, our data indicate that Alu elements have contributed to the acquisition of novel protein sequences during primate and human evolution. Comparing the A-I RNA editing levels during HEK293 (control), ADARB1 long isoform (with Alu exon) transfected, and short isoform (without Alu exon) transfected cells, each group has 3 replicates.
Project description:A549 cells were co-transfected with CRISPR/Cas9 (containing sgRNA and GFP) and HDR donor plasmids (containing RFP and puromycin). The genetic editing cells were selected by puromycin. And then, we performed RNA sequencing for transcription profiling of A549 RB1 RB1 wild-type/knockout cell lines. The raw data were processed with Tophat and cuffdiff for gene expression analysis.
Project description:Alternative mRNA splicing is a major mechanism for gene regulation and transcriptome diversity. Despite the extent of the phenomenon, the regulation and specificity of the splicing machinery are only partially understood. Adenosine-to-inosine (A-to-I) RNA editing of pre-mRNA by ADAR enzymes has been linked to splicing regulation in several cases. Here we used bioinformatics approaches, RNA-seq and exon-specific microarray of ADAR knockdown cells to globally examine how ADAR and its A-to-I RNA editing activity influence alternative mRNA splicing. Although A-to-I RNA editing only rarely targets canonical splicing acceptor, donor, and branch sites, it was found to affect splicing regulatory elements (SREs) within exons. Cassette exons were found to be significantly enriched with A-to-I RNA editing sites compared with constitutive exons. RNA-seq and exon-specific microarray revealed that ADAR knockdown in hepatocarcinoma and myelogenous leukemia cell lines leads to global changes in gene expression, with hundreds of genes changing their splicing patterns in both cell lines. This global change in splicing pattern cannot be explained by putative editing sites alone. Genes showing significant changes in their splicing pattern are frequently involved in RNA processing and splicing activity. Analysis of recently published RNA-seq data from glioblastoma cell lines showed similar results. Our global analysis reveals that ADAR plays a major role in splicing regulation. Although direct editing of the splicing motifs does occur, we suggest it is not likely to be the primary mechanism for ADAR-mediated regulation of alternative splicing. Rather, this regulation is achieved by modulating trans-acting factors involved in the splicing machinery. HepG2 and K562 cell lines were stably transfected with plasmids containing siRNA designed to specifically knock down ADAR expression (ADAR KD). This in order to examine how ADAR affects alternative splicing globally.
Project description:Alternative mRNA splicing is a major mechanism for gene regulation and transcriptome diversity. Despite the extent of the phenomenon, the regulation and specificity of the splicing machinery are only partially understood. Adenosine-to-inosine (A-to-I) RNA editing of pre-mRNA by ADAR enzymes has been linked to splicing regulation in several cases. Here we used bioinformatics approaches, RNA-seq and exon-specific microarray of ADAR knockdown cells to globally examine how ADAR and its A-to-I RNA editing activity influence alternative mRNA splicing. Although A-to-I RNA editing only rarely targets canonical splicing acceptor, donor, and branch sites, it was found to affect splicing regulatory elements (SREs) within exons. Cassette exons were found to be significantly enriched with A-to-I RNA editing sites compared with constitutive exons. RNA-seq and exon-specific microarray revealed that ADAR knockdown in hepatocarcinoma and myelogenous leukemia cell lines leads to global changes in gene expression, with hundreds of genes changing their splicing patterns in both cell lines. This global change in splicing pattern cannot be explained by putative editing sites alone. Genes showing significant changes in their splicing pattern are frequently involved in RNA processing and splicing activity. Analysis of recently published RNA-seq data from glioblastoma cell lines showed similar results. Our global analysis reveals that ADAR plays a major role in splicing regulation. Although direct editing of the splicing motifs does occur, we suggest it is not likely to be the primary mechanism for ADAR-mediated regulation of alternative splicing. Rather, this regulation is achieved by modulating trans-acting factors involved in the splicing machinery. HepG2 and K562 cell lines were stably transfected with plasmids containing siRNA designed to specifically knock down ADAR expression (ADAR KD). This in order to examine how ADAR affects alternative splicing globally.