Center for Epigenomics and Department of Genetics, Albert Einstein College of Medicine, Bronx, New York, USA.
School of Pharmaceutical Sciences, University of Geneva, Geneva, Switzerland.
CRISPR J. 2020 Jun;3(3):188-197. doi: 10.1089/crispr.2019.0077.
The CRISPR-Cas9 system can be modified to perform "epigenetic editing" by utilizing the catalytically inactive (dead) Cas9 (dCas9) to recruit regulatory proteins to specific genomic locations. In prior studies, epigenetic editing with multimers of the transactivator VP16 and guide RNAs (gRNAs) was found to cause adverse cellular responses. These side effects may confound studies inducing new cellular properties, especially if the cellular responses are maintained through cell divisions-an epigenetic regulatory property. Here, we show how distinct components of this CRISPR-dCas9 activation system, particularly dCas9 with untargeted gRNAs, upregulate genes associated with transcriptional stress, defense response, and regulation of cell death. Our results highlight a previously undetected acute stress response to CRISPR-dCas9 components in human cells, which is transient and not maintained through cell divisions.
CRISPR-Cas9 系统可以通过利用无催化活性（失活）Cas9（dCas9）来招募调节蛋白到特定的基因组位置，从而进行“表观遗传编辑”。在之前的研究中，发现使用转录激活因子 VP16 和向导 RNA（gRNA）的多聚体进行表观遗传编辑会引起细胞的不良反应。这些副作用可能会干扰诱导新的细胞特性的研究，特别是如果细胞反应通过细胞分裂来维持——这是一种表观遗传调节特性。在这里，我们展示了这种 CRISPR-dCas9 激活系统的不同组成部分，特别是靶向非特定 gRNA 的 dCas9，如何上调与转录应激、防御反应和细胞死亡调节相关的基因。我们的结果强调了以前未被发现的人类细胞中对 CRISPR-dCas9 成分的急性应激反应，这种反应是短暂的，不会通过细胞分裂来维持。
