CRISPR/Cas9 Platforms for Genome Editing in Plants: Developments and Applications

Abstract

The clustered regularly interspaced short palindromic repeat (CRISPR)-associated protein9 (Cas9) genome editing system (CRISPR/Cas9) is adapted from the prokaryotic type II adaptive immunity system. The CRISPR/Cas9 tool surpasses other programmable nucleases, such as ZFNs and TALENs, for its simplicity and high efficiency. Various plant-specific CRISPR/Cas9 vector systems have been established for adaption of this technology to many plant species. In this review, we present an overview of current advances on applications of this technology in plants, emphasizing general considerations for establishment of CRISPR/Cas9 vector platforms, strategies for multiplex editing, methods for analyzing the induced mutations, factors affecting editing efficiency and specificity, and features of the induced mutations and applications of the CRISPR/Cas9 system in plants. In addition, we provide a perspective on the challenges of CRISPR/Cas9 technology and its significance for basic plant research and crop genetic improvement.

Risk associated with off-target plant genome editing and methods for its limitation

“…Therefore, genome-wide characterization for off-target edits serves as an indicator of potential undesired phenotypic changes in genome-edited crops. In order that there is integrity in the use of comparative assessments to evaluate off-target effects in genome-edited crops, research must focus on how to alleviate off-target edits and how to assess the frequency and nature of those off-target edits that do occur [41].…”

Recessive Resistance to Plant Viruses: Potential Resistance Genes Beyond Translation Initiation Factors

“…The applications of these genome editing technologies in plants are well summarized elsewhere (Araki and Ishii, 2015; Luo et al, 2016; Ma et al, 2016). Importantly, genome editing technologies have been employed not only in model plants but also in several crop species, and they are now being applied even more widely.…”

Revolutionize Genetic Studies and Crop Improvement with High-Throughput and Genome-Scale CRISPR/Cas9 Gene Editing Technology

“…CRISPR/Cas9 (Clustered Regulatory Interspaced Short Palindromic Repeat/CRISPR associated protein 9) gene editing technology has made targeted mutagenesis easy, and the technology has successfully edited various targets in many organisms including all major crops (Ma et al, 2016). Cas9 binds to the DNA target, which is complementary to the first 20-bp sequence of the guide RNA (gRNA), and generates a double strand break (DSB) within the target site.…”

“…In rice, targeted mutagenesis by CRISPR/Cas9 is extremely efficient. It was reported that over 80% of the T 0 rice plants transformed with a CRISPR/Cas9 construct contain mutations at the intended target site (Ma et al, 2016). More importantly, the percentage of T 0 mutants that are either homozygous or bi-allelic can be as high as 90% (Ma et al, 2016).…”

“…It was reported that over 80% of the T 0 rice plants transformed with a CRISPR/Cas9 construct contain mutations at the intended target site (Ma et al, 2016). More importantly, the percentage of T 0 mutants that are either homozygous or bi-allelic can be as high as 90% (Ma et al, 2016). The observed high mutagenic efficiency and high percentage of homozygous/bi-allelic mutations makes it feasible to complete three key genetic tasks within a single generation in rice: (1) generate a CRISPR/Cas9 mutant library; (2) conduct high-throughput forward genetic screens for desired traits; (3) identify and confirm the causal mutations for the observed phenotypes.…”