CRISPR/Cas9-Mediated SlMYBS2 Mutagenesis Reduces Tomato Resistance to Phytophthora infestans

Niu

et al. 2023

IJMS

Group Ⅲ WRKY transcription factors (TFs) play pivotal roles in responding to the diverse abiotic stress and secondary metabolism of plants. However, the evolution and function of WRKY66 remains unclear. Here, WRKY66 homologs were traced back to the origin of terrestrial plants and found to have been subjected to both motifs’ gain and loss, and purifying selection. A phylogenetic analysis showed that 145 WRKY66 genes could be divided into three main clades (Clade A–C). The substitution rate tests indicated that the WRKY66 lineage was significantly different from others. A sequence analysis displayed that the WRKY66 homologs had conserved WRKY and C2HC motifs with higher proportions of crucial amino acid residues in the average abundance. The AtWRKY66 is a nuclear protein, salt- and ABA- inducible transcription activator. Simultaneously, under salt stress and ABA treatments, the superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities, as well as the seed germination rates of Atwrky66-knockdown plants generated by the clustered, regularly interspaced, short palindromic repeats/CRISPR-associated 9 (CRISPR/Cas9) system, were all lower than those of wild type (WT) plants, but the relative electrolyte leakage (REL) was higher, indicating the increased sensitivities of the knockdown plants to the salt stress and ABA treatments. Moreover, RNA-seq and qRT-PCR analyses revealed that several regulatory genes in the ABA-mediated signaling pathway involved in stress response of the knockdown plants were significantly regulated, being evidenced by the more moderate expressions of the genes. Therefore, the AtWRKY66 likely acts as a positive regulator in the salt stress response, which may be involved in an ABA-mediated signaling pathway.

Section: Introductionmentioning

confidence: 99%

Evolution of the WRKY66 Gene Family and Its Mutations Generated by the CRISPR/Cas9 System Increase the Sensitivity to Salt Stress in Arabidopsis

Niu

et al. 2023

IJMS

“…Independent studies showing CRISPR/Cas9-targeted mutagenesis of five potato susceptibility genes, Defense, No Death1, CIB1/HBI1-like 1, DMR6-1, Caffeoyl-CoA O-methyltransferase and Signal Responsive 4, conferred resistance to late blight disease (Hegde et al, 2021;Kieu et al, 2021;Moon et al, 2022). However, knocking-out of MYB transcription factor S2 by CRISPR/Cas9 produced tomato mutants susceptible to P. infestans with increased necrotic cells, lesion sizes, disease index, and reduced expression of defense-related genes, indicating that SlMYBS2 acts as a positive regulator of resistance to P. infestans (Liu et al, 2021). CRISPR/Cas9-engineered cacao plants for the susceptible gene, Non-Expressor of Pathogenesis-Related 3, exhibited enhanced resistance to Phytophthora tropicalis (Fister et al, 2018).…”

Section: Crispr/cas Mediated Resistance Against Oomycetesmentioning

confidence: 99%

Genetic amelioration of fruit and vegetable crops to increase biotic and abiotic stress resistance through CRISPR Genome Editing

Sardar

2023

Front. Plant Sci.

Environmental changes and increasing population are major concerns for crop production and food security as a whole. To address this, researchers had focussed on the improvement of cereals and pulses and have made considerable progress till the beginning of this decade. However, cereals and pulses together, without vegetables and fruits, are inadequate to meet the dietary and nutritional demands of human life. Production of good quality vegetables and fruits is highly challenging owing to their perishable nature and short shelf life as well as abiotic and biotic stresses encountered during pre- and post-harvest. Genetic engineering approaches to produce good quality, to increase shelf life and stress-resistance, and to change the time of flowering and fruit ripening by introducing foreign genes to produce genetically modified crops were quite successful. However, several biosafety concerns, such as the risk of transgene-outcrossing, limited their production, marketing, and consumption. Modern genome editing techniques, like the CRISPR/Cas9 system, provide a perfect solution in this scenario, as it can produce transgene-free genetically edited plants. Hence, these genetically edited plants can easily satisfy the biosafety norms for crop production and consumption. This review highlights the potential of the CRISPR/Cas9 system for the successful generation of abiotic and biotic stress resistance and thereby improving the quality, yield, and overall productivity of vegetables and fruits.

“…For example, Li et al [ 42 ] found that SlMYB28 , which encodes an R2R3-MYB transcription factor, is a negative regulator of the response to tomato yellow leaf curl virus (TYLCV) infection in the tomato. Liu et al [ 43 ] knocked out the SlMYBS2 gene in the tomato using CRISPR/Cas9 technology, and the number of necrotic cells, the severity of lesions, and the disease index were higher, and the resistance to Phytophthora infestation was lower in transgenic plants than in wild-type plants. Yin et al [ 44 ] showed that SlMYB1 is an important multifunctional TF that can regulate the resistance of the tomato to Botrytis cinerea .…”

Section: Discussionmentioning

confidence: 99%

Cloning, Expression, and Functional Analysis of the MYB Transcription Factor SlMYB86-like in Tomato

Chen,

Zhan,

Shao

et al. 2024

Plants

MYB transcription factors (TFs) have been shown to play a key role in plant growth and development and are in response to various types of biotic and abiotic stress. Here, we clarified the structure, expression patterns, and function of a MYB TF, SlMYB86-like (Solyc06g071690) in tomato using an inbred tomato line exhibiting high resistance to bacterial wilt (Hm 2-2 (R)) and one susceptible line (BY 1-2 (S)). The full-length cDNA sequence of this gene was 1226 bp, and the open reading frame was 966 bp, which encoded 321 amino acids; its relative molecular weight was 37.05055 kDa; its theoretical isoelectric point was 7.22; it was a hydrophilic nonsecreted protein; and it had no transmembrane structures. The protein also contains a highly conserved MYB DNA-binding domain and was predicted to be localized to the nucleus. Phylogenetic analysis revealed that SlMYB86-like is closely related to SpMYB86-like in Solanum pennellii and clustered with other members of the family Solanaceae. Quantitative real-time PCR (qRT-PCR) analysis revealed that the expression of the SlMYB86-like gene was tissue specific and could be induced by Ralstonia solanacearum, salicylic acid, and jasmonic acid. The results of virus-induced gene silencing (VIGS) revealed that SlMYB86-like silencing decreased the resistance of tomato plants to bacterial wilt, suggesting that it positively regulates the resistance of tomatoes to bacterial wilt. Overall, these findings indicate that SlMYB86-like plays a key role in regulating the resistance of tomatoes to bacterial wilt.