Homo sapiens
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ABSTRACT:
PROVIDER: PRJNA355620 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Targeted DNA methylation in vivo using an engineered dCas9-MQ1 fusion protein
| PRJNA355391 | ENA
Project description:Targeted DNA methylation in vivo using an engineered dCas9-MQ1 fusion protein (RRBS)
| PRJNA355621 | ENA
Project description:Mammalian DNA methylation is a critical epigenetic mechanism orchestrating gene expression networks in many biological processes. However, investigation of the functions of specific methylation events remains challenging. Here, we demonstrate that fusion of Tet1 or Dnmt3a with a catalytically inactive Cas9 (dCas9) enables targeted DNA methylation editing. Targeting of the dCas9-Tet1 or -Dnmt3a fusion protein to methylated or unmethylated promoter sequences caused activation or silencing, respectively, of an endogenous reporter. Targeted demethylation of the BDNF promoter IV or the MyoD distal enhancer by dCas9-Tet1 induced BDNF expression in post-mitotic neurons or activated MyoD facilitating reprogramming of fibroblasts into myoblasts, respectively. Targeted de novo methylation of a CTCF loop anchor site by dCas9-Dnmt3a blocked CTCF binding and interfered with DNA looping, causing altered gene expression in the neighboring loop. Finally, we show that these tools can edit DNA methylation in mice demonstrating their wide utility for functional studies of epigenetic regulation.
2016-09-23 | GSE83890 | GEO
Project description:Fusion of active protein domains to the nuclease-deficient clustered regularly interspaced short palindromic repeat (CRISPR) associated protein 9 (dCas9) has been widely used for epigenome editing, but the specificities of these engineered proteins have still not been fully investigated. Targeted methylation of specific gene loci offers a direct approach to perturb DNA methylation-associated biological processes. In this study, we generated and validated the global off-target characteristics of CRISPR-guided DNA methyltransferases (CRISPRme) by fusing the catalytic domain of DNMT3A or DNMT3B to the C terminus of the dCas9 protein from S. pyogenes. Using targeted quantitative bisulfite pyrosequencing and whole genome bisulfite sequencing (WGBS), we prove that CRISPRme can efficiently methylate the CpG dinucleotides flanking its target sites in genomic loci (uPA and TGFBR3) in human cells (HEK293T) with CpG-methylation levels exceeding 70% for some target sites. Using qPCR, fluorescent reporter cells, and RNA sequencing, we found that CRISPRme can mediate transient inhibition of gene expression which appears to result from Cas9-mediated interference with transcription rather than de novo DNA methylation. Analyses of whole genome methylation did not identify global methylation changes, however a substantial number of CRISPRme off-target differentially methylated regions (DMR, over 6000) were still identified. The majority of these DMRs were hypermethylated both in cells expressing CRISPRme alone and cells expressing CRISPRme together with gRNAs. These off-target hypermethylated sites were enriched in gene bodies, introns, 5’UTR, CGI shores, Alu sequences, open chromatin and PAM rich regions, but not correlated with off-target binding sites predicted by ChIP-seq. Our results prove that CRISPRme allows for efficient RNA-guided methylation of endogenous CpGs, however with high frequencies of off-target methylation indicating that further improvements of the specificity of CRISPR-dCas9 based DNA methylation modifiers are still required.
2016-12-14 | GSE92310 | GEO
Project description:Fusion of active protein domains to the nuclease-deficient clustered regularly interspaced short palindromic repeat (CRISPR) associated protein 9 (dCas9) has been widely used for epigenome editing, but the specificities of these engineered proteins have still not been fully investigated. Targeted methylation of specific gene loci offers a direct approach to perturb DNA methylation-associated biological processes. In this study, we generated and validated the global off-target characteristics of CRISPR-guided DNA methyltransferases (CRISPRme) by fusing the catalytic domain of DNMT3A or DNMT3B to the C terminus of the dCas9 protein from S. pyogenes. Using targeted quantitative bisulfite pyrosequencing and whole genome bisulfite sequencing (WGBS), we prove that CRISPRme can efficiently methylate the CpG dinucleotides flanking its target sites in genomic loci (uPA and TGFBR3) in human cells (HEK293T) with CpG-methylation levels exceeding 70% for some target sites. Using qPCR, fluorescent reporter cells, and RNA sequencing, we found that CRISPRme can mediate transient inhibition of gene expression which appears to result from Cas9-mediated interference with transcription rather than de novo DNA methylation. Analyses of whole genome methylation did not identify global methylation changes, however a substantial number of CRISPRme off-target differentially methylated regions (DMR, over 6000) were still identified. The majority of these DMRs were hypermethylated both in cells expressing CRISPRme alone and cells expressing CRISPRme together with gRNAs. These off-target hypermethylated sites were enriched in gene bodies, introns, 5’UTR, CGI shores, Alu sequences, open chromatin and PAM rich regions, but not correlated with off-target binding sites predicted by ChIP-seq. Our results prove that CRISPRme allows for efficient RNA-guided methylation of endogenous CpGs, however with high frequencies of off-target methylation indicating that further improvements of the specificity of CRISPR-dCas9 based DNA methylation modifiers are still required.
2016-12-14 | GSE92261 | GEO
Project description:We report the generation of CRISPR-dCas9 DNA methyltransferases to mediate targeted DNA methylation. Using the dCas9-BFP-DNMT3A and dCas9-BFP-DNMT3B methyltransferases, we have demonstrated that these two methyltransferase can mediate targeted methylation in three human genes tested: uPA, TGFBR3, and CDKN2A in human HEK293T cells. We also showed that these methyltransferases could mediate gene inhibition. five samples co-transfected with five uPA sgRNAs and each of the four dCas9 fusions, or control transfection with pUC19 plasmid
2016-06-01 | E-GEOD-74935 | biostudies-arrayexpress
Project description:DNA methyltransferases (DNMTs) are thought to be involved in the cellular response to DNA damage, thus linking DNA repair mechanisms with DNA methylation. This study presents a novel method of targeted DNA methylation that utilizes endogenous DNA double strand break repair pathways and applies it to the neurodegenerative disease gene C9orf72. A double strand break induced by CRISPR/cas9 in the promoter of C9orf72 is sufficient to induce DNA methylation, and methylation can be precisely targeted through the process of homology directed repair (HDR) via delivery of an in vitro methylated exogenous repair template. Long methylated double stranded DNA templates induce more methylation than shorter templates and with higher efficiency than a dCas9-DNMT3a fusion protein construct. Genome-wide methylation analysis reveals no significant off-target methylation changes when inducing methylation via HDR, whereas the dCas9-DNMT3a fusion construct causes significant off-target methylation at over 67,000 sites. This method is applied to generate a patient derived iPSC model of amyotrophic lateral sclerosis and frontotemporal dementia (ALS/FTD) that exhibits stable DNA methylation patterns similar to those seen in patients. Using this model, it’s shown for the first time that DNA methylation of the 5’ regulatory region directly reduces C9orf72 expression and increases histone H3K9 tri-methylation levels.
2019-10-11 | GSE134995 | GEO
Project description:DNA methyltransferases (DNMTs) are thought to be involved in the cellular response to DNA damage, thus linking DNA repair mechanisms with DNA methylation. This study presents a novel method of targeted DNA methylation that utilizes endogenous DNA double strand break repair pathways and applies it to the neurodegenerative disease gene C9orf72. A double strand break induced by CRISPR/cas9 in the promoter of C9orf72 is sufficient to induce DNA methylation, and methylation can be precisely targeted through the process of homology directed repair (HDR) via delivery of an in vitro methylated exogenous repair template. Long methylated double stranded DNA templates induce more methylation than shorter templates and with higher efficiency than a dCas9-DNMT3a fusion protein construct. Genome-wide methylation analysis reveals no significant off-target methylation changes when inducing methylation via HDR, whereas the dCas9-DNMT3a fusion construct causes significant off-target methylation at over 67,000 sites. This method is applied to generate a patient derived iPSC model of amyotrophic lateral sclerosis and frontotemporal dementia (ALS/FTD) that exhibits stable DNA methylation patterns similar to those seen in patients. Using this model, it’s shown for the first time that DNA methylation of the 5’ regulatory region directly reduces C9orf72 expression and increases histone H3K9 tri-methylation levels.
2019-10-11 | GSE134994 | GEO
Project description:We report the generation of CRISPR-dCas9 DNA methyltransferases to mediate targeted DNA methylation. Using the dCas9-BFP-DNMT3A and dCas9-BFP-DNMT3B methyltransferases, we have demonstrated that these two methyltransferase can mediate targeted methylation in three human genes tested: uPA, TGFBR3, and CDKN2A in human HEK293T cells. We also showed that these methyltransferases could mediate gene inhibition.
2016-06-01 | GSE74935 | GEO