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: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:Human acute myeloid leukemia cell lines OCI-AML2 and OCI-AML3 were used in a CRISPR/Cas9-mediated approach to specifically target DDX3X’s gene sequences encoding the RNA binding domain of the helicase. DDX3X RNA binding domain is bipartite in the two halves of the helicase core. sgRNAs were designed to target both halves of the domain (named RNA binding domain A and B – RBDA and RBDB). We performed RNA-seq to observe the gene expression changes in both OCI-AML2 and OCI-AML3 cell lines following the not-combined CRISPR/Cas9 –mediated targeting of both regions of the DDX3X RNA binding domain. Control CRISPR/Cas9 performed with no sgRNA expressing vector (named “empty vector”) was performed in both cell lines. The latter condition was used as a control for gene expression changes analysis, for each cell line.
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:Identifying putative transcription factor target genes by combining CRISPR/Cas9-based transcriptional activation with RNAseq in Drosophila S2R+ cells. This study focuses on the transcription factors Twist and Snail, singly and together. RNA from Drosophila cells following CRISPR/Cas9-based activation of Twist, Snail, or Twist and Snail together, compared with non-targeting sgRNA. Two biological replicates for each experiment
Project description:We sought to characterise how chromatin states affected CRISPR/Cas9 activity and the induced indel profiles. We used two different doses of Trichostatin and two different doses of a EZH2 inhibitor to modulate the chromatin state and then performed targeted DNA-seq of selected sgRNA target regions to identify the indels.
Project description:The CRISPR-Cas9 system enables efficient sequence-specific mutagenesis for creating germline mutants of model organisms. Key constraints in vivo remain the expression and delivery of active Cas9-guideRNA ribonucleoprotein complexes (RNPs) with minimal toxicity, variable mutagenesis efficiencies depending on targeting sequence, and high mutation mosaicism. Here, we established in vitro-assembled, fluorescent Cas9-sgRNA RNPs in stabilizing salt solution to achieve maximal mutagenesis efficiency in zebrafish embryos. Sequence analysis of targeted loci in individual embryos reveals highly efficient bi-allelic mutagenesis that reaches saturation at several tested gene loci. Such virtually complete mutagenesis reveals preliminary loss-of-function phenotypes for candidate genes in somatic mutant embryos for subsequent generation of stable germline mutants. We further show efficient targeting of functional non-coding elements in gene-regulatory regions using saturating mutagenesis towards uncovering functional control elements in transgenic reporters and endogenous genes. Our results suggest that in vitro assembled, fluorescent Cas9-sgRNA RNPs provide a rapid reverse-genetics tool for direct and scalable loss-of-function studies beyond zebrafish applications.
Project description:To determine gene expression changes upon CRISPR/Cas9-mediated WRN knockout in SW48 and OVK18. 72 hours after transduction of sgRNA into Cas9 expressing cells, RNA was harvested and submitted for sequencing.
Project description:To uncover, in an unbiased fashion, which elements of the 18 kb translocated region control EVI1 transcription, we devised a CRISPR/Cas9-based enhancer scanning approach. We considered all possible sgRNA target sites containing a canonical Cas9 PAM site (NGG) on both strands of the minimal 18 kb translocated region. Deep-sequencing libraries were generated by PCR amplification of sgRNA guide strands using primers that tag the product with standard Illumina adapters and a 4 bp sample barcode in a 2 step-PCR protocol.