The NAC-type transcription factor CaNAC46 regulates the salt and drought tolerance of transgenic Arabidopsis thaliana

Abstract Background The NAC (NAM, ATAF1/ATAF2, and CUC2) transcription factors belong to a large family of plant-specific transcription factors in monocot and dicot species. These transcription factors regulate the expression of stress tolerance-related genes that protect plants from various abiotic stresses, including drought, salinity, and low temperatures. Results In this study, we identified the CaNAC46 transcription factor gene in Capsicum annuum. Its open reading frame was revealed to comprise 921 bp, encoding a protein consisting of 306 amino acids, with an isoelectric point of 6.96. A phylogenetic analysis indicated that CaNAC46 belongs to the ATAF subfamily. The expression of CaNAC46 was induced by heat, cold, high salt, drought, abscisic acid, salicylic acid, and methyl jasmonate treatments. Thus, CaNAC46 may be important for the resistance of dry pepper to abiotic stresses. A subcellular localization analysis confirmed that CaNAC46 is localized in the nucleus. The overexpression of CaNAC46 improved the tolerance of transgenic Arabidopsis thaliana plants to drought and salt stresses. The CaNAC46-overexpressing lines had longer roots and more lateral roots than wild-type lines under prolonged drought and high salt stress conditions. Additionally, CaNAC46 affected the accumulation of reactive oxygen species (ROS). Moreover, CaNAC46 promoted the expression of SOD, POD, RD29B, RD20, LDB18, ABI, IAA4, and P5CS. The malondialdehyde contents were higher in TRV2-CaNAC46 lines than in wild-type plants in response to drought and salt stresses. Furthermore, the expression levels of stress-responsive genes, such as ABA2, P5CS, DREB, RD22, CAT, and POD, were down-regulated in TRV2-CaNAC46 plants. Conclusions Under saline and drought conditions, CaNAC46 is a positive regulator that activates ROS-scavenging enzymes and enhances root formation. The results of our study indicate CaNAC46 is a transcriptional regulator responsible for salinity and drought tolerance and suggest the abiotic stress-related gene regulatory mechanisms controlling this NAC transcription factor are conserved between A. thaliana and pepper.

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Maize WRKY Transcription Factor ZmWRKY79 Positively Regulates Drought Tolerance through Elevating ABA Biosynthesis

International Journal of Molecular Sciences ◽

10.3390/ijms221810080 ◽

2021 ◽

Vol 22 (18) ◽

pp. 10080

Author(s):

Faiza Gulzar ◽

Jingye Fu ◽

Chenying Zhu ◽

Jie Yan ◽

Xinglin Li ◽

...

Keyword(s):

Transcription Factors ◽

Drought Stress ◽

Drought Tolerance ◽

Lateral Roots ◽

Antioxidant Enzyme Activities ◽

Gene Promoters ◽

Abiotic Stress Response ◽

Ros Scavenging ◽

Aba Biosynthesis ◽

Phytoalexin Biosynthesis

Drought stress causes heavy damages to crop growth and productivity under global climatic changes. Transcription factors have been extensively studied in many crops to play important roles in plant growth and defense. However, there is a scarcity of studies regarding WRKY transcription factors regulating drought responses in maize crops. Previously, ZmWRKY79 was identified as the regulator of maize phytoalexin biosynthesis with inducible expression under different elicitation. Here, we elucidated the function of ZmWRKY79 in drought stress through regulating ABA biosynthesis. The overexpression of ZmWRKY79 in Arabidopsis improved the survival rate under drought stress, which was accompanied by more lateral roots, lower stomatal aperture, and water loss. ROS scavenging was also boosted by ZmWRKY79 to result in less H2O2 and MDA accumulation and increased antioxidant enzyme activities. Further analysis detected more ABA production in ZmWRKY79 overexpression lines under drought stress, which was consistent with up-regulated ABA biosynthetic gene expression by RNA-seq analysis. ZmWRKY79 was observed to target ZmAAO3 genes in maize protoplast through acting on the specific W-boxes of the corresponding gene promoters. Virus-induced gene silencing of ZmWRKY79 in maize resulted in compromised drought tolerance with more H2O2 accumulation and weaker root system architecture. Together, this study substantiates the role of ZmWRKY79 in the drought-tolerance mechanism through regulating ABA biosynthesis, suggesting its broad functions not only as the regulator in phytoalexin biosynthesis against pathogen infection but also playing the positive role in abiotic stress response, which provides a WRKY candidate gene to improve drought tolerance for maize and other crop plants.

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Overexpression of OsERF83, a Vascular Tissue-Specific Transcription Factor Gene, Confers Drought Tolerance in Rice

International Journal of Molecular Sciences ◽

10.3390/ijms22147656 ◽

2021 ◽

Vol 22 (14) ◽

pp. 7656

Author(s):

Se Eun Jung ◽

Seung Woon Bang ◽

Sung Hwan Kim ◽

Jun Sung Seo ◽

Ho-Bin Yoon ◽

...

Keyword(s):

Transcription Factor ◽

Transcription Factors ◽

Drought Tolerance ◽

Biotic Stress ◽

Abiotic Stresses ◽

Molecular Mechanisms ◽

Vascular Tissue ◽

Photochemical Efficiency ◽

Lignin Biosynthesis ◽

Pathogenesis Related Protein

Abiotic stresses severely affect plant growth and productivity. To cope with abiotic stresses, plants have evolved tolerance mechanisms that are tightly regulated by reprogramming transcription factors (TFs). APETALA2/ethylene-responsive factor (AP2/ERF) transcription factors are known to play an important role in various abiotic stresses. However, our understanding of the molecular mechanisms remains incomplete. In this study, we identified the role of OsERF83, a member of the AP2/ERF transcription factor family, in response to drought stress. OsERF83 is a transcription factor localized to the nucleus and induced in response to various abiotic stresses, such as drought and abscisic acid (ABA). Overexpression of OsERF83 in transgenic plants (OsERF83OX) significantly increased drought tolerance, with higher photochemical efficiency in rice. OsERF83OXwas also associated with growth retardation, with reduced grain yields under normal growth conditions. OsERF83 is predominantly expressed in the vascular tissue of all organs. Transcriptome analysis revealed that OsERF83 regulates drought response genes, which are related to the transporter (OsNPF8.10, OsNPF8.17, OsLH1), lignin biosynthesis (OsLAC17, OsLAC10, CAD8D), terpenoid synthesis (OsTPS33, OsTPS14, OsTPS3), cytochrome P450 family (Oscyp71Z4, CYP76M10), and abiotic stress-related genes (OsSAP, OsLEA14, PCC13-62). OsERF83 also up-regulates biotic stress-associated genes, including pathogenesis-related protein (PR), wall-associated kinase (WAK), cellulose synthase-like protein E1 (CslE1), and LysM receptor-like kinase (RLK) genes. Our results provide new insight into the multiple roles of OsERF83 in the cross-talk between abiotic and biotic stress signaling pathways.

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The AML-associated K313 mutation enhances C/EBPα activity by leading to C/EBPα overexpression

Cell Death and Disease ◽

10.1038/s41419-021-03948-6 ◽

2021 ◽

Vol 12 (7) ◽

Author(s):

Ian Edward Gentle ◽

Isabel Moelter ◽

Mohamed Tarek Badr ◽

Konstanze Döhner ◽

Michael Lübbert ◽

...

Keyword(s):

Gene Expression ◽

Cell Culture ◽

Transcription Factor ◽

Transcription Factors ◽

Transcriptional Activity ◽

Target Gene ◽

Wild Type ◽

Elevated Expression ◽

Factor C ◽

Acute Myeloid

AbstractMutations in the transcription factor C/EBPα are found in ~10% of all acute myeloid leukaemia (AML) cases but the contribution of these mutations to leukemogenesis is incompletely understood. We here use a mouse model of granulocyte progenitors expressing conditionally active HoxB8 to assess the cell biological and molecular activity of C/EBPα-mutations associated with human AML. Both N-terminal truncation and C-terminal AML-associated mutations of C/EBPα substantially altered differentiation of progenitors into mature neutrophils in cell culture. Closer analysis of the C/EBPα-K313-duplication showed expansion and prolonged survival of mutant C/EBPα-expressing granulocytes following adoptive transfer into mice. C/EBPα-protein containing the K313-mutation further showed strongly enhanced transcriptional activity compared with the wild-type protein at certain promoters. Analysis of differentially regulated genes in cells overexpressing C/EBPα-K313 indicates a strong correlation with genes regulated by C/EBPα. Analysis of transcription factor enrichment in the differentially regulated genes indicated a strong reliance of SPI1/PU.1, suggesting that despite reduced DNA binding, C/EBPα-K313 is active in regulating target gene expression and acts largely through a network of other transcription factors. Strikingly, the K313 mutation caused strongly elevated expression of C/EBPα-protein, which could also be seen in primary K313 mutated AML blasts, explaining the enhanced C/EBPα activity in K313-expressing cells.

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The intron of the Arabidopsis thaliana COX5c gene is able to improve the drought tolerance conferred by the sunflower Hahb-4 transcription factor

Planta ◽

10.1007/s00425-007-0560-9 ◽

2007 ◽

Vol 226 (5) ◽

pp. 1143-1154 ◽

Cited By ~ 19

Author(s):

Julieta V. Cabello ◽

Carlos A. Dezar ◽

Pablo A. Manavella ◽

Raquel L. Chan

Keyword(s):

Arabidopsis Thaliana ◽

Transcription Factor ◽

Drought Tolerance

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GBF3 transcription factor imparts drought tolerance in Arabidopsis thaliana

Scientific Reports ◽

10.1038/s41598-017-09542-1 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 22

Author(s):

Venkategowda Ramegowda ◽

Upinder Singh Gill ◽

Palaiyur Nanjappan Sivalingam ◽

Aarti Gupta ◽

Chirag Gupta ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Transcription Factor ◽

Drought Tolerance

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‘Garnem’ and Myrobalan ‘P.2175’: Two Different Drought Responses and Their Implications in Drought Tolerance

Horticulturae ◽

10.3390/horticulturae7090299 ◽

2021 ◽

Vol 7 (9) ◽

pp. 299

Author(s):

Beatriz Bielsa ◽

María Ángeles Sanz ◽

María José Rubio-Cabetas

Keyword(s):

Transcription Factor ◽

Drought Tolerance ◽

Abiotic Stresses ◽

Interspecific Hybrids ◽

Drought Response ◽

Breeding Programs ◽

Wide Range ◽

Relative Water ◽

Aba Content ◽

Rootstock Breeding

One of the challenges in rootstock breeding programs is the combination of tolerances to different abiotic stresses in new interspecific hybrids adapted to a wide range of environmental conditions. In this work, two Prunus L. rootstocks: Myrobalan ‘P.2175’ (P. cerasifera Ehrh.) and the almond × peach hybrid ‘Garnem’ (P. amygdalus Batsch × P. persica (L.) Batsch) were subjected to drought during 24 h to understand their drought response mechanisms. The study was conducted monitoring leaf water potential (LWP), stomatal conductance (gs), relative water content (RWC), and electrolyte leakage (EL); as well as the abscisic acid (ABA) content in roots. The relative expression of five drought-relative genes was also studied. The obtained results allowed examining the drought tolerance potential of ‘Garnem’ and Myrobalan ‘P.2175’, demonstrating the great potential of ‘Garnem’ as drought tolerance source in future selections in breeding. Furthermore, based on the obtained data, the transcription factor Myb25-like could be a good biomarker of drought sensitivity for use in Prunus rootstock breeding programs.

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CsCYT75B1, a Citrus CYTOCHROME P450 Gene, Is Involved in Accumulation of Antioxidant Flavonoids and Induces Drought Tolerance in Transgenic Arabidopsis

Antioxidants ◽

10.3390/antiox9020161 ◽

2020 ◽

Vol 9 (2) ◽

pp. 161 ◽

Cited By ~ 2

Author(s):

Muhammad Junaid Rao ◽

Yuantao Xu ◽

Xiaomei Tang ◽

Yue Huang ◽

Jihong Liu ◽

...

Keyword(s):

Cytochrome P450 ◽

Drought Stress ◽

Drought Tolerance ◽

Transgenic Arabidopsis ◽

Wild Type ◽

Ros Scavenging ◽

Cytochrome P450 Gene ◽

P450 Gene ◽

Large Gene ◽

Transgenic Lines

CYTOCHROME P450s genes are a large gene family in the plant kingdom. Our earlier transcriptome data revealed that a CYTOCHROME P450 gene of Citrus sinensis (CsCYT75B1) was associated with flavonoid metabolism and was highly induced after drought stress. Here, we characterized the function of CsCYT75B1 in drought tolerance by overexpressing it in Arabidopsis thaliana. Our results demonstrated that the overexpression of the CsCYT75B1 gene significantly enhanced the total flavonoid contents with increased antioxidant activity in transgenic Arabidopsis. The gene expression results showed that several genes that are responsible for the biosynthesis of antioxidant flavonoids were induced by 2–12 fold in transgenic Arabidopsis lines. After 14 days of drought stress, all transgenic lines displayed an enhanced tolerance to drought stress along with accumulating antioxidant flavonoids with lower superoxide radicals and reactive oxygen species (ROS) than wild type plants. In addition, drought-stressed transgenic lines possessed higher antioxidant enzymatic activities than wild type transgenic lines. Moreover, the stressed transgenic lines had significantly lower levels of electrolytic leakage than wild type transgenic lines. These results demonstrate that the CsCYT75B1 gene of sweet orange functions in the metabolism of antioxidant flavonoid and contributes to drought tolerance by elevating ROS scavenging activities.

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Class I TCP transcription factors regulate trichome branching and cuticle development in Arabidopsis

Journal of Experimental Botany ◽

10.1093/jxb/eraa257 ◽

2020 ◽

Vol 71 (18) ◽

pp. 5438-5453

Author(s):

Alejandra Camoirano ◽

Agustín L Arce ◽

Federico D Ariel ◽

Antonela L Alem ◽

Daniel H Gonzalez ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Transcription Factor ◽

Transcription Factors ◽

Regulatory Network ◽

Class I ◽

Branch Number ◽

Plant Organ ◽

Cuticle Formation ◽

Cuticle Development ◽

Different Levels

Abstract Trichomes and the cuticle are two specialized structures of the aerial epidermis that are important for plant organ development and interaction with the environment. In this study, we report that Arabidopsis thaliana plants affected in the function of the class I TEOSINTE BRANCHED 1, CYCLOIDEA, PCF (TCP) transcription factors TCP14 and TCP15 show overbranched trichomes in leaves and stems and increased cuticle permeability. We found that TCP15 regulates the expression of MYB106, a MIXTA-like transcription factor involved in epidermal cell and cuticle development, and overexpression of MYB106 in a tcp14 tcp15 mutant reduces trichome branch number. TCP14 and TCP15 are also required for the expression of the cuticle biosynthesis genes CYP86A4, GPAT6, and CUS2, and of SHN1 and SHN2, two AP2/EREBP transcription factors required for cutin and wax biosynthesis. SHN1 and CUS2 are also targets of TCP15, indicating that class I TCPs influence cuticle formation acting at different levels, through the regulation of MIXTA-like and SHN transcription factors and of cuticle biosynthesis genes. Our study indicates that class I TCPs are coordinators of the regulatory network involved in trichome and cuticle development.

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Exacerbating Autoimmune Disease with Salt

Science Signaling ◽

10.1126/scisignal.2004284 ◽

2013 ◽

Vol 6 (273) ◽

pp. ec97-ec97 ◽

Cited By ~ 1

Author(s):

Annalisa M. VanHook

Keyword(s):

T Cells ◽

Transcription Factor ◽

Autoimmune Disease ◽

Normal Diet ◽

High Salt ◽

Wild Type ◽

High Salt Diet ◽

Salt Diet ◽

Link Type

In addition to contributing to the immune response against pathogens, helper T (TH ) cells that produce the cytokine interleukin-17 (IL-17) also contribute to autoimmune diseases. Maintenance of both normal and pathogenic TH17 cell activities depends on activation of the IL-23 receptor (IL-23R). By performing transcriptional profiling and network analysis of transcriptional changes in wild-type and Il23r–/– mouse T cells that were activated and induced to differentiate into TH17 cells, Wu et al. identified serum glucocorticoid kinase 1 (Sgk1) as a key node downstream of IL-23R. In vitro differentiation of naïve T cells from Sgk1–/– mice revealed that SGK1 was not required for primary TH17 cell differentiation but was required for maintenance of TH17 cells and continued signaling through IL-23R. Analysis of experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis, in Sgk1–/– animals showed that these mice had reduced incidence of disease, severity of symptoms, and production of IL-17 compared with EAE in wild-type animals. In vitro experiments were consistent with a model in which SGK1 phosphorylates the transcription factor Foxo1 to repress its ability to indirectly activate Il23r expression. SGK1 mediates sodium (Na+) homeostasis by modulating the activity of epithelial Na+ channels, so the authors tested the effect of Na+ on TH17 cell differentiation. Increasing the concentration of NaCl in the culture medium increased expression of Sgk1, Il23r, Il17, and other genes associated with TH17 differentiation in wild-type, but not Sgk1–/–, T cells that had been activated but not treated with factors to influence their development into a particular type of TH cell. Compared with a normal diet, a high-salt diet increased the number of TH17 cells in the guts of wild-type mice but induced a milder increase in the abundance of TH17 cells in Sgk1–/– mice. In the EAE model, mice on a high-salt diet showed increased severity of disease compared with those fed a normal diet. However, a high-salt diet had a much milder effect on disease symptoms in Sgk1–/– mice. In a related study, Kleinewietfeld etal. differentiated naïve human T cells in culture conditions that mimicked the interstitial fluid of animals fed a high-salt diet and found that the additional NaCl promoted differentiation of TH17 cells that expressed markers consistent with autoimmune activity. Further experiments indicated that this effect was mediated by the kinase p38, the transcription factor and p38 target NFAT5, and the NFAT5 target Sgk1. In vivo experiments performed in this study were consistent with those reported by Wu et al. These studies suggest that production of the pathogenic TH17 cells that contribute to autoimmunity may be exacerbated by dietary salt. Commentary by O’Shea and Jones considers the implications and limitations of these findings in the context of autoimmune disease.C. Wu, N. Yosef, T. Thalhamer, C. Zhu, S. Xiao, Y. Kishi, A. Regev, V. K. Kuchroo, Induction of pathogenic TH17 cells by inducible salt-sensing kinase SGK1. Nature496, 513–517 (2013). [PubMed]M. Kleinewietfeld, A. Manzel, J. Titze, H. Kvakan, N. Yosef, R. A. Linker, D. N. Muller, D. A. Hafler, Sodium chloride drives autoimmune disease by the induction of pathogenic TH17 cells. Nature496, 518–522 (2013). [PubMed]J. J. O’Shea, R. G. Jones, Rubbing salt in the wound. Nature496, 437–439 (2013). [PubMed]

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