Targeted DNA methylation in vivo using an engineered dCas9-MQ1 fusion protein
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE90692 | GEO | 2017/08/11
SECONDARY ACCESSION(S): PRJNA355391
REPOSITORIES: GEO
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Project description:Comprehensive studies have shown that DNA methylation plays vital roles in both loss of pluripotency and governance of the transcriptome during embryogenesis and subsequent developmental processes. Aberrant DNA methylation patterns have been widely observed in tumorigenesis, ageing and neurodegenerative diseases, highlighting the importance of a systematic understanding of DNA methylation and the dynamic changes of methylomes during disease onset and progression. Here we describe a facile and convenient approach for efficient targeted DNA methylation by fusing inactive Cas9 (dCas9) with an engineered prokaryotic DNA methyltransferase MQ1. Our study presents a rapid and efficient strategy to achieve locus-specific cytosine modifications in the genome without obvious impact on global methylation in 24 h. Finally, we demonstrate our tool can induce targeted CpG methylation in mice by zygote microinjection, thereby demonstrating its potential utility in early development.
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Project description:Comprehensive studies have shown that DNA methylation plays vital roles in both loss of pluripotency and governance of the transcriptome during embryogenesis and subsequent developmental processes. Aberrant DNA methylation patterns have been widely observed in tumorigenesis, aging, and neurodegenerative diseases, highlighting the importance of a systematic understanding of DNA methylation and the dynamic changes of methylomes during disease onset and progression. Here we describe a facile and convenient approach for efficient targeted DNA methylation by fusing inactive Cas9 (dCas9) with an engineered prokaryotic DNA methyltransferase MQ1. Our study presents a lentivirus-free strategy to achieve locus-specific cytosine modifications in the genome within 24 hours. Finally, we demonstrated our tool can induce targeted CpG methylation in mice by zygote microinjection, thereby facilitating the dissection of the functional relevance of specific CpG methylation marks at endogenous loci.
2017-08-11 | GSE90690 | GEO
Project description:Comprehensive studies have shown that DNA methylation plays vital roles in both loss of pluripotency and governance of the transcriptome during embryogenesis and subsequent developmental processes. Aberrant DNA methylation patterns have been widely observed in tumorigenesis, aging, and neurodegenerative diseases, highlighting the importance of a systematic understanding of DNA methylation and the dynamic changes of methylomes during disease onset and progression. Here we describe a facile and convenient approach for efficient targeted DNA methylation by fusing inactive Cas9 (dCas9) with an engineered prokaryotic DNA methyltransferase MQ1. Our study presents a lentivirus-free strategy to achieve locus-specific cytosine modifications in the genome within 24 hours. Finally, we demonstrated our tool can induce targeted CpG methylation in mice by zygote microinjection, thereby facilitating the dissection of the functional relevance of specific CpG methylation marks at endogenous loci.
2017-08-11 | GSE90691 | GEO
Project description:Targeted DNA methylation in vivo using an engineered dCas9-MQ1 fusion protein
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Project description:Mammalian genomes exhibit complex patterns of gene expression regulated, in part, by DNA methylation. The advent of engineered DNA methyltransferases (MTases) to target DNA methylation to specific sites in the genome will accelerate many areas of biological research. However, targeted MTases require clear design rules to direct site-specific DNA methylation and minimize the unintended effects of off-target DNA methylation. Here we report a targeted MTase composed of an artificially split CpG MTase (sMTase) with one fragment fused to a catalytically-inactive Cas9 (dCas9) that directs the functional assembly of sMTase fragments at the targeted CpG site. We precisely map RNA-programmed DNA methylation to targeted CpG sites as a function of distance and orientation from the protospacer adjacent motif (PAM). Expression of the dCas9-sMTase in mammalian cells led to predictable and efficient (up to ~70%) DNA methylation at targeted sites. Multiplexing sgRNAs enabled targeting methylation to multiple sites in a single promoter and to multiple sites in multiple promoters. This programmable de novo MTase tool might be used for studying mechanisms of initiation, spreading and inheritance of DNA methylation, and for therapeutic gene silencing.
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Project description:We engineered m6A methyltransferase with dCas13-M14 to achieve site-specific editing of m6A. The resultant m6A editors can be programmed with a guide RNA, allowing functional comparison of single site methylation in different mRNA regions.
2024-10-12 | GSE185755 | GEO