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CRISPR-based targeting of DNA methylation in Arabidopsis thaliana by a bacterial CG specific DNA methyltransferase.

ABSTRACT: CRISPR-based targeted modification of epigenetic marks is an important strategy to regulate the expression of genes and their associated phenotypes in plants and animals. The manipulation of DNA cytosine methylation is particularly attractive in plants since DNA methylation changes are often heritable in subsequent plant generations. Although plants have DNA methylation in all sequence contexts (CG, CHG, CHH, where H can be any nucleotide but G), methylation at symmetrical CG sites is the most important for gene silencing, and is also the most efficiently maintained through miotic and meiotic cell divisions. Thus, DNA methylation targeting tools that directly install CG methylation are highly desirable. Here we have developed two CRISPR-based CG specific targeted DNA methylation systems for plants using the DNA methyltransferase MQ1 (SssI) from the bacterium Mollicutes spiroplasma. To reduce off-target effects, we used a variant of the enzyme with reduced catalytic activity. We demonstrate that methylation added by MQ1 is highly target-specific and can be heritably maintained in the absence of the effector. These tools should be valuable both in crop engineering and in plant genetic research.

ORGANISM(S): Arabidopsis thaliana

PROVIDER: GSE149840 | GEO | 2021/05/19

REPOSITORIES: GEO

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