Project description:Noncoding RNAs (ncRNAs) comprise an important class of natural regulators that mediate a vast array of biological processes, including the modulation of chromatin architecture. Moreover, artificial ncRNAs have revealed that the functional capabilities of RNA are extremely broad. To further investigate and harness these capabilities, we developed CRISPR-Display ("CRISP-Disp"), a targeted localization strategy that uses Cas9 to deploy large RNA cargos to specific DNA loci. We demonstrate that exogenous RNA domains can be functionally appended onto the CRISPR scaffold at multiple insertion points, allowing the construction of Cas9 complexes with RNAs nearing one kilobase in length, with structured RNAs, protein-binding cassettes, artificial aptamers and pools of random sequences. CRISP-Disp also allows the simultaneous multiplexing of disparate functions at multiple targets. We anticipate that this technology will provide a powerful method with which to ectopically localize functional RNAs and ribonuceloprotein complexes at specified genomic loci. RNA Immunoprecipitation (RIP) against FLAG-tagged Cas9 protein, coexpressed with a large pool of CRISPR RNAs bearing random internal insertions
Project description:Noncoding RNAs (ncRNAs) comprise an important class of natural regulators that mediate a vast array of biological processes, including the modulation of chromatin architecture. Moreover, artificial ncRNAs have revealed that the functional capabilities of RNA are extremely broad. To further investigate and harness these capabilities, we developed CRISPR-Display ("CRISP-Disp"), a targeted localization strategy that uses Cas9 to deploy large RNA cargos to specific DNA loci. We demonstrate that exogenous RNA domains can be functionally appended onto the CRISPR scaffold at multiple insertion points, allowing the construction of Cas9 complexes with RNAs nearing one kilobase in length, with structured RNAs, protein-binding cassettes, artificial aptamers and pools of random sequences. CRISP-Disp also allows the simultaneous multiplexing of disparate functions at multiple targets. We anticipate that this technology will provide a powerful method with which to ectopically localize functional RNAs and ribonuceloprotein complexes at specified genomic loci. Whole cell poly(A) selected RNA seq, from HEK293FT cells bearing lentivirally-integrated Gaussia and Cypridina luciferase reporter loci. Cells were transiently transfected with dCas9~VP64 alone, or with dCas9~VP and one of several modified sgRNAs,each targeting the Gaussia reporter.
Project description:Large-scale analyses have revealed that 60-90% of the mammalian genome is transcriptionally active. Because <2% of sequences have protein-coding potential, why so much cellular energy is expended on RNA synthesis is a major question in the post-genomic era. The hypothesis that RNA may serve as recruiting platforms for chromatin modifiers has gained ground with discoveries linking long ncRNAs, such as RepA, Xist, and Tsix, to locus-specific targeting of Polycomb proteins to the X-chromosome. Long ncRNAs have also been associated with Polycomb proteins at human HOX loci. Here, we ask if RNA targeting may be a general feature of regulation for mouse Polycomb repressive complex 2 (PRC2). We develop a method to capture the 'PRC2 transcriptome' by combining RNA immunoprecipitation (RIP) with deep sequencing (seq). RIP-seq of mouse embryonic stem cells identifies >3000 RNAs in the PRC2 transcriptome. Approximately 14% of RNAs originate from previously described PRC2-binding sites and many are promoter-associated. The transcriptome includes a large number of unannotated noncoding and antisense RNAs, with the X-chromosome exhibiting a high density of PRC2 RNAs. Imprinted genes and other disease genes, including those involved in cancer, are also well-represented. Functional validation of select candidates confirms RNA-PRC2 interactions in vivo and recruitment of Polycomb proteins in cis. Thus, RNA cofactors may be one general mechanism, among others, for targeting mammalian PRC2. Given PRC2's essential roles during stem cell renewal, development, and cancer, the PRC2 transcriptome described herein will provide a valuable resource for regenerative medicine and cancer biology. Identification and characterization of RNAs associated with PRC2 complex in mouse embryoinc stem cells
Project description:Noncoding RNAs (ncRNAs) comprise an important class of natural regulators that mediate a vast array of biological processes, including the modulation of chromatin architecture. Moreover, artificial ncRNAs have revealed that the functional capabilities of RNA are extremely broad. To further investigate and harness these capabilities, we developed CRISPR-Display ("CRISP-Disp"), a targeted localization strategy that uses Cas9 to deploy large RNA cargos to specific DNA loci. We demonstrate that exogenous RNA domains can be functionally appended onto the CRISPR scaffold at multiple insertion points, allowing the construction of Cas9 complexes with RNAs nearing one kilobase in length, with structured RNAs, protein-binding cassettes, artificial aptamers and pools of random sequences. CRISP-Disp also allows the simultaneous multiplexing of disparate functions at multiple targets. We anticipate that this technology will provide a powerful method with which to ectopically localize functional RNAs and ribonuceloprotein complexes at specified genomic loci.
Project description:Noncoding RNAs (ncRNAs) comprise an important class of natural regulators that mediate a vast array of biological processes, including the modulation of chromatin architecture. Moreover, artificial ncRNAs have revealed that the functional capabilities of RNA are extremely broad. To further investigate and harness these capabilities, we developed CRISPR-Display ("CRISP-Disp"), a targeted localization strategy that uses Cas9 to deploy large RNA cargos to specific DNA loci. We demonstrate that exogenous RNA domains can be functionally appended onto the CRISPR scaffold at multiple insertion points, allowing the construction of Cas9 complexes with RNAs nearing one kilobase in length, with structured RNAs, protein-binding cassettes, artificial aptamers and pools of random sequences. CRISP-Disp also allows the simultaneous multiplexing of disparate functions at multiple targets. We anticipate that this technology will provide a powerful method with which to ectopically localize functional RNAs and ribonuceloprotein complexes at specified genomic loci.
Project description:Long noncoding RNAs (lncRNAs) are a major transcriptional output of the mammalian genome, and their cellular roles are typically assayed by a variety of loss-of-function approaches. This study aims to identify the best current method to deplete nuclear lncRNAs. Small interfering RNAs (RNAi), antisense oligonucleotides (LNAs) and CRISPR interference (CRISPRi) were applied to knock down loc100289019 (a typical nuclear lncRNA, referred to as lnc289) in HeLa cells. We generated sequencing libraries after performing each step of each method, up to and including depletion of lnc289. Differential expression analyses between libraries generated before and after each step allowed us to evaluate the effect of that step on gene expression. The transcriptional effect of lncRNA depletion was then compared to the magnitude of off-target effects inherent to each method.
Project description:Here we present Perturb-ATAC, a method which combines multiplexed CRISPR interference or knockout with genome-wide chromatin accessibility profiling in single cells, based on the simultaneous detection of CRISPR guide RNAs and open chromatin sites by Assay of Transposase-accessible Chromatin with sequencing (ATAC-seq). We applied Perturb-ATAC to transcription factors (TFs), chromatin-modifying factors, and noncoding RNAs (ncRNAs) in ~3,700 single cells, encompassing more than 75 unique genotype-phenotype relationships.
Project description:Here we present Perturb-ATAC, a method which combines multiplexed CRISPR interference or knockout with genome-wide chromatin accessibility profiling in single cells, based on the simultaneous detection of CRISPR guide RNAs and open chromatin sites by Assay of Transposase-accessible Chromatin with sequencing (ATAC-seq). We applied Perturb-ATAC to transcription factors (TFs), chromatin-modifying factors, and noncoding RNAs (ncRNAs) in ~3,700 single cells, encompassing more than 75 unique genotype-phenotype relationships.