Kckout of the Entire Family of AITR Genes in Arabidopsis Leads to Enhanced Abiotic Stress Tolerance Without Fitness Costs

Abstract Backgorund Environmental stresses including abiotic stresses and biotic stresses limit yield of plants. Stress-tolerant breeding is an efficient way to improve plant yield under stress conditions. Genome editing by CRISPR/Cas9 can be used in molecular breeding to improve agronomic traits in crops, but in most cases, with fitness costs. The plant hormone ABA regulates plant responses to abiotic stresses via signaling transduction. We previously identified AITRs as a family of novel transcription factors that play a role in regulating plant responses to ABA and abiotic stresses. We found that abiotic stress tolerance was increased in the single, double and triple aitr mutants. However, it is unclear if the increased abiotic stress tolerance in the mutants may have fitness costs. Results We report here the characterization of AITRs as suitable candidate genes for CRISPR/Cas9 editing to improve plant stress tolerance. By using CRISPR/Cas9 to target AITR3 and AITR4 simultaneously in the aitr256 triple and aitr1256 quadruple mutants respectively, we generated Cas9-free aitr23456 quintuple and aitr123456 sextuple mutants. We found that reduced sensitivities to ABA and enhanced tolerance to drought and salt were observed in these mutants. Most importantly, plant growth and development was not affected even in the aitr123456 sextuple mutants, in whom the entire AITR family genes have been knocked out, and the aitr123456 sextuple mutants also showed a wild type response to the pathogen infection. Conclusions Our results suggest that knockout of the AITR family genes in Arabidopsis enhanced abiotic stress tolerance without fitness costs. Considering that knock-out a few AITRs will lead to enhanced abiotic stress tolerance, that AITRs are widely distributed in angiosperms with multiple encoding genes, AITRs may be targeted for molecular breeding to improve abiotic stress tolerance in plants including crops.

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Mutation of GmAITR Genes by CRISPR/Cas9 Genome Editing Results in Enhanced Salinity Stress Tolerance in Soybean

Frontiers in Plant Science ◽

10.3389/fpls.2021.779598 ◽

2021 ◽

Vol 12 ◽

Author(s):

Tianya Wang ◽

Hongwei Xun ◽

Wei Wang ◽

Xiaoyang Ding ◽

Hainan Tian ◽

...

Keyword(s):

Abiotic Stress ◽

Stress Tolerance ◽

Genome Editing ◽

Salinity Tolerance ◽

Field Experiments ◽

Agronomic Traits ◽

Abiotic Stress Tolerance ◽

Pcr Analysis ◽

Aba Signaling ◽

Entire Family

Breeding of stress-tolerant plants is able to improve crop yield under stress conditions, whereas CRISPR/Cas9 genome editing has been shown to be an efficient way for molecular breeding to improve agronomic traits including stress tolerance in crops. However, genes can be targeted for genome editing to enhance crop abiotic stress tolerance remained largely unidentified. We have previously identified abscisic acid (ABA)-induced transcription repressors (AITRs) as a novel family of transcription factors that are involved in the regulation of ABA signaling, and we found that knockout of the entire family of AITR genes in Arabidopsis enhanced drought and salinity tolerance without fitness costs. Considering that AITRs are conserved in angiosperms, AITRs in crops may be targeted for genome editing to improve abiotic stress tolerance. We report here that mutation of GmAITR genes by CRISPR/Cas9 genome editing leads to enhanced salinity tolerance in soybean. By using quantitative RT-PCR analysis, we found that the expression levels of GmAITRs were increased in response to ABA and salt treatments. Transfection assays in soybean protoplasts show that GmAITRs are nucleus proteins, and have transcriptional repression activities. By using CRISPR/Cas9 to target the six GmAITRs simultaneously, we successfully generated Cas9-free gmaitr36 double and gmaitr23456 quintuple mutants. We found that ABA sensitivity in these mutants was increased. Consistent with this, ABA responses of some ABA signaling key regulator genes in the gmaitr mutants were altered. In both seed germination and seedling growth assays, the gmaitr mutants showed enhanced salt tolerance. Most importantly, enhanced salinity tolerance in the mutant plants was also observed in the field experiments. These results suggest that mutation of GmAITR genes by CRISPR/Cas9 is an efficient way to improve salinity tolerance in soybean.

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Calcium-Dependent Protein Kinases (CDPK) in Abiotic Stress Tolerance

THE JOURNAL OF PLANT SCIENCE RESEARCH ◽

10.32381/jpsr.2018.34.02.15 ◽

2018 ◽

Vol 34 (2) ◽

pp. 259-265 ◽

Cited By ~ 2

Author(s):

Hemant B Kardile ◽

◽

Vikrant ◽

Nirmal Kant Sharma ◽

Ankita Sharma ◽

...

Keyword(s):

Abiotic Stress ◽

Stress Tolerance ◽

Protein Kinases ◽

Abiotic Stress Tolerance ◽

Calcium Dependent ◽

Dependent Protein ◽

Calcium Dependent Protein Kinases

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Roles of Nitric Oxide in Conferring Multiple Abiotic Stress Tolerance in Plants and Crosstalk with Other Plant Growth Regulators

Journal of Plant Growth Regulation ◽

10.1007/s00344-021-10446-8 ◽

2021 ◽

Author(s):

Rajesh Kumar Singhal ◽

Hanuman Singh Jatav ◽

Tariq Aftab ◽

Saurabh Pandey ◽

Udit Nandan Mishra ◽

...

Keyword(s):

Nitric Oxide ◽

Abiotic Stress ◽

Plant Growth ◽

Stress Tolerance ◽

Plant Growth Regulators ◽

Growth Regulators ◽

Abiotic Stress Tolerance

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Genome-Wide Identification and Expression Profiling of the PDI Gene Family Reveals Their Probable Involvement in Abiotic Stress Tolerance in Tomato (Solanum lycopersicum L.)

Genes ◽

10.3390/genes12010023 ◽

2020 ◽

Vol 12 (1) ◽

pp. 23

Author(s):

Antt Htet Wai ◽

Muhammad Waseem ◽

A B M Mahbub Morshed Khan ◽

Ujjal Kumar Nath ◽

Do Jin Lee ◽

...

Keyword(s):

Abiotic Stress ◽

Gene Family ◽

Stress Tolerance ◽

Solanum Lycopersicum ◽

Expression Profiling ◽

Abiotic Stress Tolerance ◽

Dependent Manner ◽

Solanum Lycopersicum L ◽

Genome Wide ◽

Protein Disulfide

Protein disulfide isomerases (PDI) and PDI-like proteins catalyze the formation and isomerization of protein disulfide bonds in the endoplasmic reticulum and prevent the buildup of misfolded proteins under abiotic stress conditions. In the present study, we conducted the first comprehensive genome-wide exploration of the PDI gene family in tomato (Solanum lycopersicum L.). We identified 19 tomato PDI genes that were unevenly distributed on 8 of the 12 tomato chromosomes, with segmental duplications detected for 3 paralogous gene pairs. Expression profiling of the PDI genes revealed that most of them were differentially expressed across different organs and developmental stages of the fruit. Furthermore, most of the PDI genes were highly induced by heat, salt, and abscisic acid (ABA) treatments, while relatively few of the genes were induced by cold and nutrient and water deficit (NWD) stresses. The predominant expression of SlPDI1-1, SlPDI1-3, SlPDI1-4, SlPDI2-1, SlPDI4-1, and SlPDI5-1 in response to abiotic stress and ABA treatment suggested they play regulatory roles in abiotic stress tolerance in tomato in an ABA-dependent manner. Our results provide new insight into the structure and function of PDI genes and will be helpful for the selection of candidate genes involved in fruit development and abiotic stress tolerance in tomato.

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Citric Acid-Mediated Abiotic Stress Tolerance in Plants

International Journal of Molecular Sciences ◽

10.3390/ijms22137235 ◽

2021 ◽

Vol 22 (13) ◽

pp. 7235

Author(s):

Md. Tahjib-Ul-Arif ◽

Mst. Ishrat Zahan ◽

Md. Masudul Karim ◽

Shahin Imran ◽

Charles T. Hunter ◽

...

Keyword(s):

Abiotic Stress ◽

Citric Acid ◽

Stress Tolerance ◽

Metabolic Networks ◽

Abiotic Stress Tolerance ◽

Heavy Metal Stress ◽

Stress Conditions ◽

Growth And Yield ◽

Antioxidant Defense Systems ◽

Physiological Outcomes

Several recent studies have shown that citric acid/citrate (CA) can confer abiotic stress tolerance to plants. Exogenous CA application leads to improved growth and yield in crop plants under various abiotic stress conditions. Improved physiological outcomes are associated with higher photosynthetic rates, reduced reactive oxygen species, and better osmoregulation. Application of CA also induces antioxidant defense systems, promotes increased chlorophyll content, and affects secondary metabolism to limit plant growth restrictions under stress. In particular, CA has a major impact on relieving heavy metal stress by promoting precipitation, chelation, and sequestration of metal ions. This review summarizes the mechanisms that mediate CA-regulated changes in plants, primarily CA’s involvement in the control of physiological and molecular processes in plants under abiotic stress conditions. We also review genetic engineering strategies for CA-mediated abiotic stress tolerance. Finally, we propose a model to explain how CA’s position in complex metabolic networks involving the biosynthesis of phytohormones, amino acids, signaling molecules, and other secondary metabolites could explain some of its abiotic stress-ameliorating properties. This review summarizes our current understanding of CA-mediated abiotic stress tolerance and highlights areas where additional research is needed.

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Utilization of genes encoding osmoprotectants in transgenic plants for enhanced abiotic stress tolerance

Electronic Journal of Biotechnology ◽

10.1016/j.ejbt.2015.04.002 ◽

2015 ◽

Vol 18 (4) ◽

pp. 257-266 ◽

Cited By ~ 49

Author(s):

Mohammad Sayyar Khan ◽

Dawood Ahmad ◽

Muhammad Adil Khan

Keyword(s):

Abiotic Stress ◽

Transgenic Plants ◽

Stress Tolerance ◽

Abiotic Stress Tolerance ◽

Genes Encoding

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Enhanced Abiotic Stress Tolerance of Vicia faba L. Plants Heterologously Expressing the PR10a Gene from Potato

Plants ◽

10.3390/plants10010173 ◽

2021 ◽

Vol 10 (1) ◽

pp. 173

Author(s):

Abeer F. Desouky ◽

Ahmed H. Ahmed ◽

Hartmut Stützel ◽

Hans-Jörg Jacobsen ◽

Yi-Chen Pao ◽

...

Keyword(s):

Salt Stress ◽

Abiotic Stress ◽

Stress Tolerance ◽

Vicia Faba ◽

Faba Bean ◽

Abiotic Stress Tolerance ◽

Wild Type ◽

Stress Injury ◽

Bean Plants ◽

Vicia Faba L

Pathogenesis-related (PR) proteins are known to play relevant roles in plant defense against biotic and abiotic stresses. In the present study, we characterize the response of transgenic faba bean (Vicia faba L.) plants encoding a PR10a gene from potato (Solanum tuberosum L.) to salinity and drought. The transgene was under the mannopine synthetase (pMAS) promoter. PR10a-overexpressing faba bean plants showed better growth than the wild-type plants after 14 days of drought stress and 30 days of salt stress under hydroponic growth conditions. After removing the stress, the PR10a-plants returned to a normal state, while the wild-type plants could not be restored. Most importantly, there was no phenotypic difference between transgenic and non-transgenic faba bean plants under well-watered conditions. Evaluation of physiological parameters during salt stress showed lower Na+-content in the leaves of the transgenic plants, which would reduce the toxic effect. In addition, PR10a-plants were able to maintain vegetative growth and experienced fewer photosystem changes under both stresses and a lower level of osmotic stress injury under salt stress compared to wild-type plants. Taken together, our findings suggest that the PR10a gene from potato plays an important role in abiotic stress tolerance, probably by activation of stress-related physiological processes.

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