Roles of Arabidopsis WRKY3 and WRKY4 Transcription Factors in Plant Responses to Pathogens

The Brassicaceae plant family contains many economically important crops such as Brassica napus L., Brassica rapa L., Brassica oleracea L., Brassica juncea L., Eruca sativa Mill., Camelina sativa L. and Raphanus sativus L. Insufficient data on the genetic regulation of agronomic traits in these species complicates the editing of their genomes. In recent years, the attention of the academic community has been drawn to anthocyanin hyperaccumulation. This trait is not only beneficial for human health, but can also increase plant resistance to stress. MYB transcription factors are the main regulators of flavonoid biosynthesis in plants. Some of them are well studied in Arabidopsis thaliana. The AtMYB60 gene is a transcriptional repressor of anthocyanin biosynthesis, and it also negatively impacts plant responses to drought stress. Myb60 is one of the least studied transcription factors with similar functions in Brassicaceae. There is a high degree of homology between predicted MYB60 genes of A. thaliana and related plant species. However, functions of these homologous genes have never been studied. Gene knockout by CRISPR/Cas technology remains the easiest way to perform genome editing in order to discover the role of individual plant genes. Disruption of genes acting as negative regulators of anthocyanin biosynthesis could result in color staining of plant tissues and an increase in stress tolerance. In the present study, we investigated the AtMYB60 gene and its homologs in Brassicaceae plants and suggested universal gRNAs to knockout these genes. Keywords: CRISPR, Brassicaceae, MYB60, knockout, anthocyanin

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Light spectra trigger divergent gene expression in barley cultivars

10.1101/2021.02.03.429565 ◽

2021 ◽

Author(s):

Arantxa Monteagudo ◽

Álvaro Rodríguez del Río ◽

Bruno Contreras-Moreira ◽

Tibor Kiss ◽

Marianna Mayer ◽

...

Keyword(s):

Transcription Factors ◽

Light Quality ◽

Frost Tolerance ◽

Early Spring ◽

Plant Responses ◽

Genotypic Differences ◽

Light Sources ◽

Diverse Range ◽

Barley Cultivars ◽

Light Spectra

AbstractLight spectra influence barley development, causing a diverse range of responses among cultivars that are poorly understood. Here, we exposed three barley genotypes with different light sensitivities to two light sources: fluorescent bulbs, over-representing green and red wavebands, and metal halide lamps, with a more balanced spectrum. We used RNA sequencing to identify the main genes and pathways involved in the different responses, and RT-qPCR to validate the expression values. Different grades of sensitivity to light spectra were associated with transcriptional reprogramming, plastid signals, and photosynthesis. The genotypes were especially divergent in the expression of genes regulated by transcription factors from MADS-box, WRKY, and NAC families, and in specific photoreceptors such as phytochromes and cryptochromes. Variations in light spectra also affected the expression of circadian clock, flowering time, and frost tolerance genes, among others, resembling plant responses to temperature. The relation between PPD-H1, HvVRN1, and HvFT1 expression might explain genotypic differences. Light-sensitive genotypes experienced a partial reversion of the vernalization process and senescence-related stress under the less favorable light quality conditions. The observed light-quality sensitivities reveal a complex mechanism of adaptation to regions with specific light quality features and/or possible regulation of light spectra in plant development during early spring.HighlightDevelopment genes were affected by light quality in the barley varieties tested. Different grades of sensitivity were related to the expression of transcription factors, senescence, light signaling and cold-regulated genes.

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TGA transcription factors and jasmonate-independent COI1 signalling regulate specific plant responses to reactive oxylipins

Journal of Experimental Botany ◽

10.1093/jxb/ers389 ◽

2013 ◽

Vol 64 (4) ◽

pp. 963-975 ◽

Cited By ~ 53

Author(s):

Henrik U. Stotz ◽

Stefan Mueller ◽

Maria Zoeller ◽

Martin J. Mueller ◽

Susanne Berger

Keyword(s):

Transcription Factors ◽

Plant Responses ◽

Tga Transcription Factors

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The Role of Stress-Responsive Transcription Factors in Modulating Abiotic Stress Tolerance in Plants

Agronomy ◽

10.3390/agronomy10060788 ◽

2020 ◽

Vol 10 (6) ◽

pp. 788 ◽

Cited By ~ 4

Author(s):

Youngdae Yoon ◽

Deok Hyun Seo ◽

Hoyoon Shin ◽

Hui Jin Kim ◽

Chul Min Kim ◽

...

Keyword(s):

Transcription Factors ◽

Abiotic Stress ◽

Stress Tolerance ◽

Stress Responses ◽

Abiotic Stresses ◽

Crop Production ◽

Global Climate ◽

Abiotic Stress Tolerance ◽

Plant Responses ◽

Plant Tolerance

Abiotic stresses, such as drought, high temperature, and salinity, affect plant growth and productivity. Furthermore, global climate change may increase the frequency and severity of abiotic stresses, suggesting that development of varieties with improved stress tolerance is critical for future sustainable crop production. Improving stress tolerance requires a detailed understanding of the hormone signaling and transcriptional pathways involved in stress responses. Abscisic acid (ABA) and jasmonic acid (JA) are key stress-response hormones in plants, and some stress-responsive transcription factors such as ABFs and MYCs function as direct components of ABA and JA signaling, playing a pivotal role in plant tolerance to abiotic stress. In addition, extensive studies have identified other stress-responsive transcription factors belonging to the NAC, AP2/ERF, MYB, and WRKY families that mediate plant response and tolerance to abiotic stress. These suggest that transcriptional regulation of stress-responsive genes is an essential step to determine the mechanisms underlying plant stress responses and tolerance to abiotic stress, and that these transcription factors may be important targets for development of crops with enhanced abiotic stress tolerance. In this review, we briefly describe the mechanisms underlying plant abiotic stress responses, focusing on ABA and JA metabolism and signaling pathways. We then summarize the diverse array of transcription factors involved in plant responses to abiotic stress, while noting their potential applications for improvement of stress tolerance.

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Jasmonic Acid-dependent MYC Transcription Factors Bind to a Tandem G-box Motif in the YUCCA8 and YUCCA9 Promoters to Regulate Biotic Stress Responses

10.20944/preprints202107.0142.v1 ◽

2021 ◽

Author(s):

Marta-Marina Pérez-Alonso ◽

Betriz Sánchez-Parra ◽

Paloma Ortiz-García ◽

Estrella Santamaría ◽

Isabel Díaz ◽

...

Keyword(s):

Transcription Factors ◽

Jasmonic Acid ◽

Stress Responses ◽

Pyruvic Acid ◽

Biotic Stress ◽

De Novo ◽

Higher Plants ◽

Plant Responses ◽

Mechanical Wounding ◽

Promoter Regions

The indole-3-pyruvic acid pathway is the major route for auxin biosynthesis in higher plants. Tryptophan aminotransferases (TAA1/TAR) and members of the YUCCA family of flavin-containing monooxygenases catalyze the conversion of L-tryptophan via indole-3-pyruvic acid into indole-3-acetic acid (IAA). It has been described that locally produced jasmonic acid (JA) in response to mechanical wounding, triggers de novo-formation of IAA through the induction of two YUCCA genes, YUC8 and YUC9. Here, we report the direct involvement of a small number of basic helix-loop-helix transcription factors of the MYC family in this process. We show that the JA-mediated regulation of YUC8 and YUC9 gene expression depends on the abundance of MYC2, MYC3, and MYC4. In support of this observation, seedlings of myc knockout mutants displayed a strongly reduced response to JA-mediated IAA formation. In addition, transactivation assays provided experimental evidence for the binding of the MYC transcription factors to a particular tandem G-box motif abundant in the promoter regions of YUC8 and YUC9, but not in those of the other YUCCA genes. Moreover, we clearly demonstrate that YUC8ox and YUC9ox overexpressing plants show less damage after spider mite infestation, thereby underlining a role of auxin in plant responses toward biotic stress cues.

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Valine-Glutamine Proteins in Plant Responses to Oxygen and Nitric Oxide

Frontiers in Plant Science ◽

10.3389/fpls.2020.632678 ◽

2021 ◽

Vol 11 ◽

Author(s):

José León ◽

Beatriz Gayubas ◽

Mari-Cruz Castillo

Keyword(s):

Nitric Oxide ◽

Transcription Factors ◽

Transcriptional Regulators ◽

Plant Responses ◽

Extreme Temperatures ◽

Transcriptome Data ◽

Wrky Transcription Factors ◽

Regulate Gene Expression ◽

Encoding Genes ◽

Wrky Proteins

Multigene families coding for valine-glutamine (VQ) proteins have been identified in all kind of plants but chlorophytes. VQ proteins are transcriptional regulators, which often interact with WRKY transcription factors to regulate gene expression sometimes modulated by reversible phosphorylation. Different VQ-WRKY complexes regulate defense against varied pathogens as well as responses to osmotic stress and extreme temperatures. However, despite these well-known functions, new regulatory activities for VQ proteins are still to be explored. Searching public Arabidopsis thaliana transcriptome data for new potential targets of VQ-WRKY regulation allowed us identifying several VQ protein and WRKY factor encoding genes that were differentially expressed in oxygen-related processes such as responses to hypoxia or ozone-triggered oxidative stress. Moreover, some of those were also differentially regulated upon nitric oxide (NO) treatment. These subsets of VQ and WRKY proteins might combine into different VQ-WRKY complexes, thus representing a potential regulatory core of NO-modulated and O2-modulated responses. Given the increasing relevance that gasotransmitters are gaining as plant physiology regulators, and particularly considering the key roles exerted by O2 and NO in regulating the N-degron pathway-controlled stability of transcription factors, VQ and WRKY proteins could be instrumental in regulating manifold processes in plants.

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Transcriptional integration of plant responses to iron availability

Journal of Experimental Botany ◽

10.1093/jxb/eraa556 ◽

2020 ◽

Author(s):

Fei Gao ◽

Christian Dubos

Keyword(s):

Transcription Factors ◽

Regulatory Networks ◽

Iron Homeostasis ◽

Future Research ◽

Plant Responses ◽

Transcriptional Regulatory Networks ◽

Helix Loop Helix ◽

Regulatory Cascade ◽

Transcriptional Regulatory ◽

Electron Transport Chains

Abstract Iron is one of the most important micronutrients for plant growth and development. It functions as the enzyme cofactor or component of electron transport chains in various vital metabolic processes, including photosynthesis, respiration, and amino acid biosynthesis. To maintain iron homeostasis, and therefore prevent any deficiency or excess that could be detrimental, plants have evolved complex transcriptional regulatory networks to tightly control iron uptake, translocation, assimilation, and storage. These regulatory networks are composed of various transcription factors; among them, members of the basic helix-loop-helix (bHLH) family play an essential role. Here, we first review recent advances in understanding the roles of bHLH transcription factors involved in the regulatory cascade controlling iron homeostasis in the model plant Arabidopsis, and extend this understanding to rice and other plant species. The importance of other classes of transcription factors will also be discussed. Second, we elaborate on the post-translational mechanisms involved in the regulation of these regulatory networks. Finally, we provide some perspectives on future research that should be conducted in order to precisely understand how plants control the homeostasis of this micronutrient.

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Strawberry FaNAC2 Enhances Tolerance to Abiotic Stress by Regulating Proline Metabolism

Plants ◽

10.3390/plants9111417 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1417

Author(s):

Jiahui Liang ◽

Jing Zheng ◽

Ze Wu ◽

Hongqing Wang

Keyword(s):

Gene Expression ◽

Transcription Factors ◽

Abiotic Stress ◽

Plant Responses ◽

Drought Treatment ◽

Abscisic Acid Biosynthesis ◽

Positive Role ◽

Transgenic Lines ◽

Response To Stress ◽

Simulated Drought

The quality and yields of strawberry plants are seriously affected by abiotic stress every year. NAC (NAM, ATAF, CUC) transcription factors are plant-specific, having various functions in plant development and response to stress. In our study, FaNAC2 from strawberry (Fragaria × ananassa, cultivar “Benihoppe”) was isolated and found to be a member of the ATAF sub-family, belonging to the NAC family of transcription factors. FaNAC2 was strongly expressed in the shoot apical meristem and older leaves of strawberries, and was induced by cold, high salinity, and drought stress. To investigate how FaNAC2 functions in plant responses to abiotic stress, transgenic Nicotiana benthamiana plants ectopically overexpressing FaNAC2 were generated. The transgenic plants grew better under salt and cold stress, and, during simulated drought treatment, these transgenic lines not only grew better, but also showed higher seed germination rates than wild-type plants. Gene expression analysis revealed that key genes in proline biosynthesis pathways were up-regulated in FaNAC2 overexpression lines, while its catabolic pathway genes were down-regulated and proline was accumulated more with the overexpression of FaNAC2 after stress treatments. Furthermore, the gene expression of abscisic acid biosynthesis was also promoted. Our results demonstrate that FaNAC2 plays an important positive role in response to different abiotic stresses and may be further utilized to improve the stress tolerance of strawberry plants.

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CDF transcription factors: plant regulators to deal with extreme environmental conditions

Journal of Experimental Botany ◽

10.1093/jxb/eraa088 ◽

2020 ◽

Vol 71 (13) ◽

pp. 3803-3815 ◽

Cited By ~ 4

Author(s):

Begoña Renau-Morata ◽

Laura Carrillo ◽

Jose Dominguez-Figueroa ◽

Jesús Vicente-Carbajosa ◽

Rosa V Molina ◽

...

Keyword(s):

Transcription Factors ◽

Plant Species ◽

Stress Responses ◽

Environmental Conditions ◽

Functional Characterization ◽

Plant Responses ◽

Large Set ◽

Cell Integrity ◽

Wide Range ◽

Adverse Environmental Conditions

Abstract In terrestrial environments, water and nutrient availabilities and temperature conditions are highly variable, and especially in extreme environments limit survival, growth, and reproduction of plants. To sustain growth and maintain cell integrity under unfavourable environmental conditions, plants have developed a variety of biochemical and physiological mechanisms, orchestrated by a large set of stress-responsive genes and a complex network of transcription factors. Recently, cycling DOF factors (CDFs), a group of plant-specific transcription factors (TFs), were identified as components of the transcriptional regulatory networks involved in the control of abiotic stress responses. The majority of the members of this TF family are activated in response to a wide range of adverse environmental conditions in different plant species. CDFs regulate different aspects of plant growth and development such as photoperiodic flowering-time control and root and shoot growth. While most of the functional characterization of CDFs has been reported in Arabidopsis, recent data suggest that their diverse roles extend to other plant species. In this review, we integrate information related to structure and functions of CDFs in plants, with special emphasis on their role in plant responses to adverse environmental conditions.

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