Centre for Molecular Medicine Norway, University of Oslo, Oslo, Norway.
Department of Informatics, Computational Biology Unit, University of Bergen, Bergen, Norway.
Elife. 2021 Dec 13;10:e75415. doi: 10.7554/eLife.75415.
Precision CRISPR gene editing relies on the cellular homology-directed DNA repair (HDR) to introduce custom DNA sequences to target sites. The HDR editing efficiency varies between cell types and genomic sites, and the sources of this variation are incompletely understood. Here, we have studied the effect of 450 DNA repair protein-Cas9 fusions on CRISPR genome editing outcomes. We find the majority of fusions to improve precision genome editing only modestly in a locus- and cell-type specific manner. We identify Cas9-POLD3 fusion that enhances editing by speeding up the initiation of DNA repair. We conclude that while DNA repair protein fusions to Cas9 can improve HDR CRISPR editing, most need to be optimized to the cell type and genomic site, highlighting the diversity of factors contributing to locus-specific genome editing outcomes.
精确的 CRISPR 基因编辑依赖于细胞同源定向 DNA 修复 (HDR) 将自定义 DNA 序列引入靶位点。HDR 编辑效率在细胞类型和基因组位置之间存在差异，并且这种差异的来源尚不完全清楚。在这里，我们研究了 450 种 DNA 修复蛋白-Cas9 融合物对 CRISPR 基因组编辑结果的影响。我们发现大多数融合物仅以局部和细胞类型特异性的方式适度改善精确基因组编辑。我们鉴定出 Cas9-POLD3 融合物通过加速 DNA 修复的起始来增强编辑。我们得出结论，虽然 Cas9 的 DNA 修复蛋白融合可以改善 HDR CRISPR 编辑，但大多数融合物需要针对细胞类型和基因组位置进行优化，这突出了导致特定基因座基因组编辑结果的多样性因素。
