Development of Improved Fruit, Vegetable, and Ornamental Crops Using the CRISPR/Cas9 Genome Editing Technique

Abstract

Horticultural crops, including fruit, vegetable, and ornamental plants are an important component of the agriculture production systems and play an important role in sustaining human life. With a steady growth in the world's population and the consequent need for more food, sustainable and increased fruit and vegetable crop production is a major challenge to guarantee future food security. Although conventional breeding techniques have significantly contributed to the development of important varieties, new approaches are required to further improve horticultural crop production. Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) has emerged as a valuable genome-editing tool able to change DNA sequences at precisely chosen loci. The CRISPR/Cas9 system was developed based on the bacterial adaptive immune system and comprises of an endonuclease guided by one or more single-guide RNAs to generate double-strand breaks. These breaks can then be repaired by the natural cellular repair mechanisms, during which genetic mutations are introduced. In a short time, the CRISPR/Cas9 system has become a popular genome-editing technique, with numerous examples of gene mutation and transcriptional regulation control in both model and crop plants. In this review, various aspects of the CRISPR/Cas9 system are explored, including a general presentation of the function of the CRISPR/Cas9 system in bacteria and its practical application as a biotechnological tool for editing plant genomes, particularly in horticultural crops.

Development of a Highly Efficient Multiplex Genome Editing System in Outcrossing Tetraploid Alfalfa (Medicago sativa)

“…CRISPR/Cas9 has become a cutting-edge technology to provide an opportunity for more effective crop improvement than other commonly used methods ( Cong et al, 2013 ; Mali et al, 2013 ; Xie et al, 2015 ; Wang et al, 2016 ; Park et al, 2017 ; Zhang et al, 2018 ; Erpen-Dalla et al, 2019 ; Jiang et al, 2019 ; Johansen et al, 2019 ; Tofazzal, 2019 ; Oh et al, 2020 ; Niu et al, 2020 ; Zhang et al, 2020 ). Regardless of substantial achievements in several crops, the efficiency of the CRISPR/Cas9 system in alfalfa is still challenging ( Meng et al, 2017 ; Gao et al, 2018 ), which necessitate the development of a robust and effective CRISPR/Cas9 genome editing system.…”

“…Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) has become the most preferred genome editing tool, enabling continuous success in genetic manipulation of many crops ( Voytas and Gao, 2014 ; Ma et al, 2016 ; Wang et al, 2016 ; Meng et al, 2017 ; Barry et al, 2018 ; Zhang et al, 2018 ; Erpen-Dalla et al, 2019 ; Jiang et al, 2019 ; Johansen et al, 2019 ; Tofazzal, 2019 ; Oh et al, 2020 ; Niu et al, 2020 ; Zhang et al, 2020 ). To date, several polyploid crops have been successfully edited by the gRNA-CRISPR/Cas9 genome editing system, including wheat ( Triticum aestivum ), cotton ( Gossypium hirsutum ), rapeseed ( Brassica napus ), and potato ( Solanum tuberosum ) ( Wang et al, 2014 ; Sun et al, 2015 ; Wang et al, 2016 ; Andersson et al, 2017 ; Cai et al, 2017 ; Zhang et al, 2017 ; Kanazashi et al, 2018 ; Kusano et al, 2018 ; Johansen et al, 2019 ).…”

A Revolution toward Gene-Editing Technology and Its Application to Crop Improvement

“…CRISPR/Cas9 Maize ARGOS8 Drought tolerance [157] CRISPR/Cas9 Rice OsNAC041 Salinity tolerance [158] CRISPR/Cas9 Tomato NPRI Drought tolerance [159] CRISPR/Cas9 Soybean Drb2a and Drb2b Salt and drought tolerance [153] CRISPR/Cas9 Tomato SIMAPK3 Drought tolerance [154] CRISPR/Cas9 Tomato SIAGL6 Heat stress [123] CRISPR/Cas9 Grapes WRKY52, Biotic stress responses [155] CRISPR/Cas9 Soybean SAPK1 and SAPK2 Salinity tolerance [160] CRISPR/Cas9 Maize ZmHKT1 Salinity tolerance [161] CRISPR/Cas9 Rice OsMPK2, OsPDS, OsBADH2…”

CRISPR/Cas9 high-throughput screening in cancer research

“…When DNA is broken, cells undergo homology directed repair (HDR) or non-homologous end joining (NHEL) to repair themselves [28]. HDR uses another homologous chromosome as a template to repair gene; normally, it does not cause mutations [29]. However, NHEL has a false-prone tendency and causes unexpected base insertion of deletion at the fracture site, resulting in transcoding mutation and functional loss of the target base.9 Now, CRISPR/Cas9 technology mainly uses this feature to knock out specific DNA fragments [30].…”