Multiplex genome editing technologies for revolutionizing plant biology and crop Improvement

Authors: ABDELRAHMAN, MODAMED - Agricultural Research Center Of Egypt; WEI, ZHENG - Chinese Academy Of Agriculture & Mechanical Sciences; Rohila, Jai; ZHAO, KAIJUN - Chinese Academy Of Agricultural Sciences

Submitted to: Frontiers in Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/1/2021
Publication Date: 10/6/2021
Citation: Abdelrahman, M., Wei, Z., Rohila, J.S., Zhao, K. 2021. Multiplex genome editing technologies for revolutionizing plant biology and crop Improvement. Frontiers in Plant Science. https://doi.org/10.3389/fpls.2021.721203.
DOI: https://doi.org/10.3389/fpls.2021.721203

Interpretive Summary: Gene editing tools are newly developed technology for creating targeted variations in genomic DNA at a locus of interest. CRISPR-Cas9 system is one of the latest gene editing tools that is comprised of clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein (Cas) components. Recently, this technology has become a choice of researchers owing to its relative ease of use and precision. CRISPR-Cas system uses sequence complementarity of the specifically designed guide RNA (gRNA). Over the past two-to-three years the CRISPR-Cas technology has advanced tremendously. One such advancement is from using a single guide approach to a multiplex strategy commonly known as ‘multiplex genome editing’ (MGE). MGE takes advantage of expressing multiple gRNAs for editing multiple loci at once. Research has shown that MGE can be extremely useful for understanding complex biological mechanisms and for improving plant traits that were difficult to modify/edit by conventional plant breeding tools. In this review article, we briefly describe MGE tools and discuss recent progress made towards their development and utilization by highlighting updates on advancements of CRISPR/Cas applications for editing multiple loci and/or genes for crop improvement programs.

Technical Abstract: Multiplex genome editing (MGE) technologies are recently developed versatile bioengineering tools for modifying two or more specific DNA loci in a genome with high precision. These genome editing tools have greatly increased the feasibility of introducing desired changes at multiple nucleotide levels into a target genome. Particularly, the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas) [CRISPR/Cas] system-based MGE tools allow generating direct mutations precisely in multiple genes simultaneously in a single event. MGE is nourishing the field of plant molecular biology as well as providing capabilities for revolutionizing the modern crop breeding methods as it was virtually impossible to edit genomes so precisely at single base pair level with prior genome editing tools such as zinc-finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs). Recently, researchers have not only started using the multiplex genome editing tools to advance the genome editing applications in certain plant science fields, but also trying to decipher and answer basic questions related to plant biology. In this review, we discuss current progress made towards the development and utilization of MGE tools with greater emphasis on the enhancement of plant biology following the discovery of CRISPR/Cas9. Further, updates on advancements of CRISPR/Cas applications for editing multiple genes are described. Finally, insights on the strengths and importance of the MGE technology in advancing crop improvement programs are presented.