Ontology highlight
ABSTRACT:
PROVIDER: PRJNA939024 | ENA |
REPOSITORIES: ENA
Similar Datasets
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.
2016-05-01 | E-MTAB-4143 | biostudies-arrayexpress
Project description:Scalable production of uniform and mature organoids in a 3D geometrically-engineered permeable membrane
| PRJNA1057805 | ENA
Project description:RNA-guided nucleases (RGNs) based on CRISPR systems permit installing short and large edits within eukaryotic genomes. However, precise genome editing is often hindered due to nuclease off- target activities and the multiple-copy character of the vast majority of chromosomal sequences. Dual nicking RGNs and high-specificity RGNs both exhibit low off-target activities. Here, we report that high-specificity Cas9 nucleases are convertible into nicking Cas9D10A variants whose precision is superior to that of the commonly used Cas9D10A nickase. Dual nicking RGNs based on a selected group of these Cas9D10A variants can yield gene knockouts and gene knock-ins at frequencies similar to or higher than those achieved by their conventional counterparts. Moreover, high-specificity dual nicking RGNs are capable of distinguishing highly similar sequences by “tiptoeing” over pre-existing single base-pair polymorphisms. Finally, high-specificity RNA-guided nicking complexes generally preserve genomic integrity, as demonstrated by unbiased genome-wide high-throughput sequencing assays. Thus, in addition to substantially enlarging the Cas9 nickase toolkit, we demonstrate the feasibility in expanding the range and precision of genome editing procedures. The herein introduced tools and multi-tier high-specificity genome editing strategies might be particularly beneficial whenever predictability and/or safety of genetic manipulations are paramount.
2020-12-08 | GSE153471 | GEO
Project description:A Scalable Epitope Tagging Approach for High Throughput ChIP-seq Analysis ChIP-seq comparison between CRISPR editing cells using epitope antibody and non-editing cells using endogeneous TF antibody
2016-09-01 | E-GEOD-78064 | biostudies-arrayexpress
Project description:The discovery that enhancers are regulated transcription units, encoding eRNAs, has raised new questions about the mechanisms of their activation. Here, we report an unexpected molecular mechanism that underlies ligand-dependent enhancer activation, based on DNA nicking to relieve torsional stress from eRNA synthesis. Using dihydrotestosterone (DHT)-induced binding of androgen receptor (AR) to prostate cancer cell enhancers as a model, we show rapid recruitment, within minutes, of DNA topoisomerase I (TOP1) to a large cohort of AR-regulated enhancers. Furthermore, we show that the DNA nicking activity of TOP1 is a prerequisite for robust eRNA synthesis and enhancer activation and is kinetically accompanied by the recruitment of ATR and the MRN complex, followed by additional components of DNA damage repair machinery to the AR-regulated enhancers. Together, our studies reveal a linkage between eRNA synthesis and ligand-dependent TOP1-mediated nicking - a strategy exerting quantitative effects on eRNA expression in regulating AR-bound enhancer-dependent transcriptional programs. Genome-wide binding analysis of AR, TOP1, MRE11 in prostate cancer cell line LNCaP with or without 5alpha-dihydrotestosterone (DHT) treatment. Nascent RNA analysis by global nuclear run-on (GRO-seq) in LNCaP cells transfected with siRNA with or without DHT treatment. Distribution of transcriptionally engaged RNA Pol II in LNCaP cells with or without DHT treatment by precision nuclear run-on and sequencing (PRO-seq).
2015-01-22 | E-GEOD-63202 | biostudies-arrayexpress
Project description:Advances in single-cell genomics enable commensurate improvements in methods for uncovering lineage relations among individual cells. Current sequencing based methods for cell lineage analysis depend on low resolution bulk analysis or rely on extensive single cell sequencing which is not scalable and could be biased by functional dependencies. Here we show an integrated biochemical-computational platform for generic single-cell lineage analysis that is retrospective, cost-effective and scalable. It consists of a biochemical-computational pipeline that inputs individual cells, produces targeted single-cell sequencing data and uses it to generate a lineage tree of the input cells. We validated the platform by applying it to cells sampled from an ex vivo grown tree and analyzed its feasibility landscape by computer simulations. We conclude that the platform may serve as a generic tool for lineage analysis and thus pave the way towards large-scale human cell lineage discovery.
2016-04-18 | E-MTAB-4553 | biostudies-arrayexpress
Project description:The discovery that enhancers are regulated transcription units, encoding eRNAs, has raised new questions about the mechanisms of their activation. Here, we report an unexpected molecular mechanism that underlies ligand-dependent enhancer activation, based on DNA nicking to relieve torsional stress from eRNA synthesis. Using dihydrotestosterone (DHT)-induced binding of androgen receptor (AR) to prostate cancer cell enhancers as a model, we show rapid recruitment, within minutes, of DNA topoisomerase I (TOP1) to a large cohort of AR-regulated enhancers. Furthermore, we show that the DNA nicking activity of TOP1 is a prerequisite for robust eRNA synthesis and enhancer activation and is kinetically accompanied by the recruitment of ATR and the MRN complex, followed by additional components of DNA damage repair machinery to the AR-regulated enhancers. Together, our studies reveal a linkage between eRNA synthesis and ligand-dependent TOP1-mediated nicking - a strategy exerting quantitative effects on eRNA expression in regulating AR-bound enhancer-dependent transcriptional programs.
2015-01-22 | GSE63202 | GEO