Project description:By a robust unbiased ChIP-seq approach, we demonstrated that CRISPR/Cas9 had crRNA-specific off-target binding activities in human genome. However, most of those binding off-targets could not be efficiently cleaved both in vivo and in vitro which suggested the cleavage off-target activity of CRISPR/Cas9 in human genome is very limited. We provided a valuable tool to further investigate the molecular mechanism of CRISPR/Cas9 and to optimize its in vivo targeting sgRNA binding sites were identified with ChipSeq by using GFP antibody (there are 2 replicates for egfa-t1 sgRNA,emx1 sgRNA and control without sgRNA in Hek293T cells, one egfa-t1 sgRNA,emx1 sgRNA and control without sgRNA in HeLaS3 cells)
Project description:Estrogen Receptor a (ERa) bindning to DNA was profiled by ChIP-seq in MCF-7 and T47D cells transduced with either control sgRNA, or sgRNA targeting a specific enhancer region (enhancer588). ERa in MCF-7 and T47D control or enhancer588-targeted cells
Project description:Analysis of Cas9/sgRNA mutagenic activity at a variety of loci in zebrafish. Each loci has a control, where no Cas9/sgRNA were injected. This is amplicon sequencing with Illumina, after PCR amplification. Data was processed with ampliCan R package version 1.1.1.
Project description:Analysis of Cas9/sgRNA mutagenic activity at a variety of loci in zebrafish. Each loci has a control, where no Cas9/sgRNA were injected. This is amplicon sequencing with Illumina, after PCR amplification. Data was processed with ampliCan R package version 1.1.1.
Project description:Human cancer cell lines indicated in the file names, with stably overexpressed Cas9 nuclease, were transfected with (C) control sgRNA or (P) TP53-specific sgRNA, (K) KRAS-specific sgRNA or (M) CMYC-specific sgRNA. Each experiment was done by transfection of sgRNA pair - control (C) or causing a NHEJ-mediated knock-out of the target genes (P, K or M). Samples for proteomics were collected 48h post sgRNA transfection without selection, in three biological replicates each (indicated with numbers 1-3). In cell lines with three activated oncogenes, three separate oncogene-targeting transfections were carried out.
Project description:RNA-guided genome editing with the CRISPR-Cas9 system has great potential for basic and clinical research, but the determinants of targeting specificity and the extent of off-target cleavage remain insufficiently understood. Using chromatin immunoprecipitation and high-throughput sequencing (ChIP-seq), we mapped genome-wide binding sites of catalytically inactive Cas9 (dCas9) in HEK293T cells, in combination with 12 different single guide RNAs (sgRNAs). The number of off-target sites bound by dCas9 varied from ~10 to >1,000 depending on the sgRNA. Analysis of off-target binding sites showed the importance of the PAM-proximal region of the sgRNA guiding sequence and that dCas9 binding sites are enriched in open chromatin regions. When targeted with catalytically active Cas9, some off-target binding sites had indels above background levels in a region around the ChIP-seq peak, but generally at lower rates than the on-target sites. Our results elucidate major determinants of Cas9 targeting, and we show that ChIP-seq allows unbiased detection of Cas9 binding sites genome-wide 1.sgRNA1-6 binding sites were identified with ChipSeq by using HA antibody (there are 2 replicates for sgRNA1-3, one sample for sgRNA4-6,one control without sgRNA) 2.PCR products which amplifies " off-target genomic sites" were deep sequenced in the presence of WT Cas9+sgRNA or WT Cas9 alone( unique adaptor was used for each sgRNA and mixed for multiplex run)
Project description:Genome-wide CRISPR-Cas9 knockout screen using TKOv1 sgRNA library performed in isogenic RBM10-proficient and RBM10-deficient HCC827 cells.
Project description:Genome-wide CRISPR-Cas9 knockout screen using TKOv1 sgRNA library was performed in isogenic RBM10-proficient and RBM10-deficient HCC827 cells.
Project description:SARS-CoV-2 lineage B.1.1.7 viruses are more transmissible, may lead to greater clinical severity, and result in modest reductions in antibody neutralization. Subgenomic RNA(sgRNA) is produced by discontinuous transcription of the SARS-CoV-2 genome. Applying our tool(periscope) to ARTIC Network Nanopore genomic sequencing data from 4400 SARS-CoV-2 positive clinical samples, we show that normalised sgRNA is significantly increased in B.1.1.7(alpha) infections(n=879). This increase is seen over the previous dominant circulating UK lineage, B.1.177(n=943), which is independent of genomic reads, E-gene cycle-threshold and days since symptom onset at sampling. A noncanonical sgRNA which could represent ORF9b is found in 98.4% of B.1.1.7 SARS-CoV-2 infections compared with only 13.8% of other lineages, with a 16-fold increase in median sgRNA abundance. We demonstrate that ORF9b protein levels are increased 6-fold in B.1.1.7 compared to a B lineage virus during in vitro culture. We hypothesise that this enhanced presence of ORF9b in B.1.1.7 viruses is a direct consequence of a triple nucleotide mutation in nucleocapsid(28280:GAT>CAT,D3L) creating a transcription regulatory-like sequence complementary to a region 3’ of the genomic leader. These findings provide a unique insight into the biology of B.1.1.7 and support monitoring of sgRNA profiles in sequence data to evaluate emerging potential variants of concern.