Modulation of DNA double-strand break repair as a strategy to improve precise genome editing

Oncogene. 2020 Oct;39(41):6393-6405. doi: 10.1038/s41388-020-01445-2. Epub 2020 Sep 3.

Abstract

In the present day, it is possible to incorporate targeted mutations or replace a gene using genome editing techniques such as customisable CRISPR/Cas9 system. Although induction of DNA double-strand breaks (DSBs) by genome editing tools can be repaired by both non-homologous end joining (NHEJ) and homologous recombination (HR), the skewness of the former pathway in human and other mammals normally result in imprecise repair. Scientists working at the crossroads of DNA repair and genome editing have devised new strategies for using a specific pathway to their advantage. Refinement in the efficiency of precise gene editing was witnessed upon downregulation of NHEJ by knockdown or using small molecule inhibitors on one hand, and upregulation of HR proteins and addition of HR stimulators, other hand. The exploitation of cell cycle phase differences together with appropriate donor DNA length/sequence and small molecules has provided further improvement in precise genome editing. The present article reviews the mechanisms of improving the efficiency of precise genome editing in several model organisms and in clinics.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • CRISPR-Cas Systems / genetics
  • DNA Breaks, Double-Stranded*
  • DNA End-Joining Repair / drug effects*
  • DNA End-Joining Repair / genetics
  • DNA Repair Enzymes / antagonists & inhibitors*
  • DNA Repair Enzymes / metabolism
  • DNA-Binding Proteins / antagonists & inhibitors
  • DNA-Binding Proteins / metabolism
  • Gene Editing / methods*
  • Gene Knockdown Techniques
  • Homologous Recombination / drug effects*
  • Homologous Recombination / genetics
  • Humans
  • Models, Animal
  • Oligonucleotides, Antisense / pharmacology
  • Pyrimidines / pharmacology
  • Schiff Bases / pharmacology

Substances

  • 5,6-bis(benzylideneamino)-2-mercaptopyrimidin-4-ol
  • DNA-Binding Proteins
  • Oligonucleotides, Antisense
  • Pyrimidines
  • Schiff Bases
  • DNA Repair Enzymes