美国普林斯顿大学Britt Adamson和加州大学Jonathan S. Weissman研究组合作绘制DNA 双链断裂 (DSB)修复的遗传图谱。该研究于2021年10月20日发表于国际一流学术期刊《细胞》杂志上。

为了系统地绘制这些通路，他们开发了一种称为 Repair-seq 的高通量筛选方法，该方法可以测量数千种遗传扰动对在目标 DNA 损伤处引入突变的影响。使用 Repair-seq，他们分析了在存在或不存在用于同源定向修复 (HDR) 的寡核苷酸的情况下，在敲除参与 DSB 修复或相关过程的 476 个基因后，由两种可编程核酸酶（Cas9 和 Cas12a）诱导的 DSB 修复产物。由此产生的数据支持对 DSB 末端连接和 HDR 路径进行有原则的、数据驱动的推理。

对这些数据的系统询问揭示了 DSB 修复基因之间意外关系，并证明了具有表面相似序列结构的修复结果可能具有明显不同的遗传依赖性。这项工作为绘制 DNA 修复途径和优化跨不同模式的基因组编辑奠定了基础。

据介绍，细胞通过一系列对维持基因组完整性至关重要的复杂途径修复DSB。

附：英文原文

Title: Mapping the genetic landscape of DNA double-strand break repair

Author: Jeffrey A. Hussmann, Jia Ling, Purnima Ravisankar, Jun Yan, Ann Cirincione, Albert Xu, Danny Simpson, Dian Yang, Anne Bothmer, Cecilia Cotta-Ramusino, Jonathan S. Weissman, Britt Adamson

Issue&Volume: 2021-10-20

Abstract: Cells repair DNA double-strand breaks (DSBs) through a complex set of pathways critical for maintaining genomic integrity. To systematically map these pathways, we developed a high-throughput screening approach called Repair-seq that measures the effects of thousands of genetic perturbations on mutations introduced at targeted DNA lesions. Using Repair-seq, we profiled DSB repair products induced by two programmable nucleases (Cas9 and Cas12a) in the presence or absence of oligonucleotides for homology-directed repair (HDR) after knockdown of 476 genes involved in DSB repair or associated processes. The resulting data enabled principled, data-driven inference of DSB end joining and HDR pathways. Systematic interrogation of this data uncovered unexpected relationships among DSB repair genes and demonstrated that repair outcomes with superficially similar sequence architectures can have markedly different genetic dependencies. This work provides a foundation for mapping DNA repair pathways and for optimizing genome editing across diverse modalities.

DOI: 10.1016/j.cell.2021.10.002

Source: https://www.cell.com/cell/fulltext/S0092-8674(21)01176-4