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Enhancement of homology-directed repair with chromatin donor templates in cells.

ABSTRACT: A key challenge in precise genome editing is the low efficiency of homology-directed repair (HDR). Here we describe a strategy for increasing the efficiency of HDR in cells by using a chromatin donor template instead of a naked DNA donor template. The use of chromatin, which is the natural form of DNA in the nucleus, increases the frequency of HDR-edited clones as well as homozygous editing. In addition, transfection of chromatin results in negligible cytotoxicity. These findings suggest that a chromatin donor template should be useful for a wide range of HDR applications such as the precise insertion or replacement of DNA fragments that contain the coding regions of genes.

SUBMITTER: Cruz-Becerra G

PROVIDER: S-EPMC7244325 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Enhancement of homology-directed repair with chromatin donor templates in cells.

Cruz-Becerra Grisel G Kadonaga James T JT

eLife 20200428

A key challenge in precise genome editing is the low efficiency of homology-directed repair (HDR). Here we describe a strategy for increasing the efficiency of HDR in cells by using a chromatin donor template instead of a naked DNA donor template. The use of chromatin, which is the natural form of DNA in the nucleus, increases the frequency of HDR-edited clones as well as homozygous editing. In addition, transfection of chromatin results in negligible cytotoxicity. These findings suggest that a ...[more]

PMID: 32343230

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