CRISPR-Based Genetic Switches and Other Complex Circuits: Research and Application.

Pei Du,Weijia Wei,Chunbo Lou,Xuejin Zhao,Xiangyu Ji,Qihui Wang

doi:10.3390/life11111255

Abstract

CRISPR-based enzymes have offered a unique capability to the design of genetic switches, with advantages in designability, modularity and orthogonality. CRISPR-based genetic switches operate on multiple levels of life, including transcription and translation. In both prokaryotic and eukaryotic cells, deactivated CRISPR endonuclease and endoribonuclease have served in genetic switches for activating or repressing gene expression, at both transcriptional and translational levels. With these genetic switches, more complex circuits have been assembled to achieve sophisticated functions including inducible switches, non-linear response and logical biocomputation. As more CRISPR enzymes continue to be excavated, CRISPR-based genetic switches will be used in a much wider range of applications.

Highlights

IntroductionPublisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations
The nearly infinite number of possible oligonucleotide sequences offers unrivaled potential for orthogonality. Conventional genetic switches, such as the transcription factors (TFs)-based switches, operate only on a transcription level, but the diverse nature of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) systems allows the development of genetic switches that control gene expression through both transcription and translation, which greatly expands the territory of gene regulation
The first widely used CRISPR-based genetic switches functioning at transcription level are the CRISPR/dCas9 systems designed based on the Cas9 endonuclease, an RNAguided DNA endonuclease originating from subtype II of the class 2 CRISPR system [57]

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Conventional genetic switches, such as the TF-based switches, operate only on a transcription level, but the diverse nature of CRISPR systems allows the development of genetic switches that control gene expression through both transcription and translation, which greatly expands the territory of gene regulation By harnessing these unique features, a large number of highly modular and orthogonal CRISPR-based genetic switches have been developed in recent years (Table 1).

CRISPR-Based Genetic Switches in Transcription Level

CRISPR-Based in Translation

Schematic of CRISPR-based genetic switches in translational

Application of CRISPR-Based Switches in Genetic Circuits

Conclusions