Effects of 24-Epibrassinolide, Bikinin, and Brassinazole on Barley Growth under Salinity Stress Are Genotype- and Dose-Dependent

Brassinosteroids (BRs) are involved in the regulation of many plant developmental processes and stress responses. In the presented study, we found a link between plant growth under salinity stress and sensitivity to 24-epibrassinolide (24-EBL, the most active phytohormone belonging to BRs), brassinazole (Brz) and bikinin (inhibitors of BR biosynthesis and signaling pathways, respectively). Plant sensitivity to treatment with active substances and salinity stress was genotype-dependent. Cv. Haruna Nijo was more responsive during the lamina joint inclination test, and improved shoot and root growth at lower concentrations of 24-EBL and bikinin under salinity stress, while cv. Golden Promise responded only to treatments of higher concentration. The use of Brz resulted in significant dose-dependent growth inhibition, greater for cv. Haruna Nijo. The results indicated that BR biosynthesis and/or signaling pathways take part in acclimation mechanisms, however, the regulation is complex and depends on internal (genotypic and tissue/organ sensitivity) and external factors (stress). Our results also confirmed that the lamina joint inclination test is a useful tool to define plant sensitivity to BRs, and to BR-dependent salinity stress. The test can be applied to manipulate the growth and stress responses of crops in agricultural practice or to select plants that are sensitive/tolerant to salinity stress in the plant breeding projects.

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Transcription Factors Interact with ABA through Gene Expression and Signaling Pathways to Mitigate Drought and Salinity Stress

Biomolecules ◽

10.3390/biom11081159 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1159

Author(s):

Quaid Hussain ◽

Muhammad Asim ◽

Rui Zhang ◽

Rayyan Khan ◽

Saqib Farooq ◽

...

Keyword(s):

Gene Expression ◽

Transcription Factors ◽

Signaling Pathways ◽

Salinity Stress ◽

Stress Responses ◽

Regulation Of Gene Expression ◽

Plant Responses ◽

Biological Processes ◽

Mads Box ◽

Abiotic Stressors

Among abiotic stressors, drought and salinity seriously affect crop growth worldwide. In plants, research has aimed to increase stress-responsive protein synthesis upstream or downstream of the various transcription factors (TFs) that alleviate drought and salinity stress. TFs play diverse roles in controlling gene expression in plants, which is necessary to regulate biological processes, such as development and environmental stress responses. In general, plant responses to different stress conditions may be either abscisic acid (ABA)-dependent or ABA-independent. A detailed understanding of how TF pathways and ABA interact to cause stress responses is essential to improve tolerance to drought and salinity stress. Despite previous progress, more active approaches based on TFs are the current focus. Therefore, the present review emphasizes the recent advancements in complex cascades of gene expression during drought and salinity responses, especially identifying the specificity and crosstalk in ABA-dependent and -independent signaling pathways. This review also highlights the transcriptional regulation of gene expression governed by various key TF pathways, including AP2/ERF, bHLH, bZIP, DREB, GATA, HD-Zip, Homeo-box, MADS-box, MYB, NAC, Tri-helix, WHIRLY, WOX, WRKY, YABBY, and zinc finger, operating in ABA-dependent and -independent signaling pathways.

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Genome-Wide Identification of the B-BOX Genes that Respond to Multiple Ripening Related Signals in Sweet Cherry Fruit

International Journal of Molecular Sciences ◽

10.3390/ijms22041622 ◽

2021 ◽

Vol 22 (4) ◽

pp. 1622

Author(s):

Yanyan Wang ◽

Zefeng Zhai ◽

Yueting Sun ◽

Chen Feng ◽

Xiang Peng ◽

...

Keyword(s):

Signaling Pathways ◽

Stress Responses ◽

Fruit Development ◽

Sweet Cherry ◽

Anthocyanin Biosynthesis ◽

Expression Patterns ◽

Light Induction ◽

Promoter Regions ◽

Genome Database ◽

Gene Structures

B-BOX proteins are zinc finger transcription factors that play important roles in plant growth, development, and abiotic stress responses. In this study, we identified 15 PavBBX genes in the genome database of sweet cherry. We systematically analyzed the gene structures, clustering characteristics, and expression patterns of these genes during fruit development and in response to light and various hormones. The PavBBX genes were divided into five subgroups. The promoter regions of the PavBBX genes contain cis-acting elements related to plant development, hormones, and stress. qRT-PCR revealed five upregulated and eight downregulated PavBBX genes during fruit development. In addition, PavBBX6, PavBBX9, and PavBBX11 were upregulated in response to light induction. We also found that ABA, BR, and GA3 contents significantly increased in response to light induction. Furthermore, the expression of several PavBBX genes was highly correlated with the expression of anthocyanin biosynthesis genes, light-responsive genes, and genes that function in multiple hormone signaling pathways. Some PavBBX genes were strongly induced by ABA, GA, and BR treatment. Notably, PavBBX6 and PavBBX9 responded to all three hormones. Taken together, BBX proteins likely play major roles in regulating anthocyanin biosynthesis in sweet cherry fruit by integrating light, ABA, GA, and BR signaling pathways.

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Oxidative Stress-Induced Alteration of Plant Central Metabolism

Life ◽

10.3390/life11040304 ◽

2021 ◽

Vol 11 (4) ◽

pp. 304

Author(s):

Tatyana Savchenko ◽

Konstantin Tikhonov

Keyword(s):

Oxidative Stress ◽

Stress Responses ◽

Tricarboxylic Acid Cycle ◽

Strong Dependence ◽

Plant Stress ◽

Metabolite Profile ◽

Agricultural Practice ◽

Central Metabolism ◽

Metabolic Markers ◽

Sugar Derivatives

Oxidative stress is an integral component of various stress conditions in plants, and this fact largely determines the substantial overlap in physiological and molecular responses to biotic and abiotic environmental challenges. In this review, we discuss the alterations in central metabolism occurring in plants experiencing oxidative stress. To focus on the changes in metabolite profile associated with oxidative stress per se, we primarily analyzed the information generated in the studies based on the exogenous application of agents, inducing oxidative stress, and the analysis of mutants displaying altered oxidative stress response. Despite of the significant variation in oxidative stress responses among different plant species and tissues, the dynamic and transient character of stress-induced changes in metabolites, and the strong dependence of metabolic responses on the intensity of stress, specific characteristic changes in sugars, sugar derivatives, tricarboxylic acid cycle metabolites, and amino acids, associated with adaptation to oxidative stress have been detected. The presented analysis of the available data demonstrates the oxidative stress-induced redistribution of metabolic fluxes targeted at the enhancement of plant stress tolerance through the prevention of ROS accumulation, maintenance of the biosynthesis of indispensable metabolites, and production of protective compounds. This analysis provides a theoretical basis for the selection/generation of plants with improved tolerance to oxidative stress and the development of metabolic markers applicable in research and routine agricultural practice.

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A microbiota–root–shoot circuit favours Arabidopsis growth over defence under suboptimal light

Nature Plants ◽

10.1038/s41477-021-00956-4 ◽

2021 ◽

Author(s):

Shiji Hou ◽

Thorsten Thiergart ◽

Nathan Vannier ◽

Fantin Mesny ◽

Jörg Ziegler ◽

...

Keyword(s):

Stress Responses ◽

Photosynthetically Active Radiation ◽

Bacterial Community Composition ◽

Light Condition ◽

Long Distance ◽

Active Radiation ◽

Light Manipulation ◽

Growth Deficiency ◽

Dependent Growth ◽

Control Light

AbstractBidirectional root–shoot signalling is probably key in orchestrating stress responses and ensuring plant survival. Here, we show that Arabidopsis thaliana responses to microbial root commensals and light are interconnected along a microbiota–root–shoot axis. Microbiota and light manipulation experiments in a gnotobiotic plant system reveal that low photosynthetically active radiation perceived by leaves induces long-distance modulation of root bacterial communities but not fungal or oomycete communities. Reciprocally, microbial commensals alleviate plant growth deficiency under low photosynthetically active radiation. This growth rescue was associated with reduced microbiota-induced aboveground defence responses and altered resistance to foliar pathogens compared with the control light condition. Inspection of a set of A. thaliana mutants reveals that this microbiota- and light-dependent growth–defence trade-off is directly explained by belowground bacterial community composition and requires the host transcriptional regulator MYC2. Our work indicates that aboveground stress responses in plants can be modulated by signals from microbial root commensals.

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The Influence of Irradiation Temperature on U.V. Induced Defect Creation in Dry Silica

MRS Proceedings ◽

10.1557/proc-61-177 ◽

1985 ◽

Vol 61 ◽

Cited By ~ 26

Author(s):

R. A. B. Devine ◽

C. Fiori ◽

J. Robertson

Keyword(s):

Oxygen Vacancy ◽

Peroxy Radical ◽

Irradiation Temperature ◽

Threshold Temperature ◽

Peroxy Radicals ◽

Oxygen Hole ◽

Spin Resonance ◽

Dependent Growth ◽

Dose Dependent ◽

Annealing Curve

ABSTRACTElectron spin resonance measurements have been carried out on samples of Suprasil Wl (dry silica) subjected to ultraviolet laser radiation (λ = 248 nm, E = 5 eV/photon). Studies have been made for fixed irradiation temperature (room) variable accumulated ultraviolet dose and fixed accumulated dose (3000 J/cm2) at various irradiation temperatures in the range 110 K to 335 K. Three principal defect centers are observed. Non-bridging oxygen hole centers are created at all temperatures in the range studied with slightly higher efficiency at room temperature (ration 300 K/150 K ∼ 2.5). Comparison of the dose dependent growth curve of the 4.8 eV absorption and its isochronal annealing curve with those for the oxygen hole center clearly identify the origin of the absorption band with this defect. A threshold temperature ∼ 200 K is found for oxygen vacancy creation consistent with results on single crystalline quartz. Post irradiation annealing at 593 K eliminates the vacancy centers and the peroxy radical resonance appears. Its growth as a function of accumulated ultraviolet dose and irradiation temperature supports the hypothesis that peroxy radicals form by the trapping of diffusing, molecular oxygen at the oxygen vacancy center.

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Antioxidative and Metabolic Contribution to Salinity Stress Responses in Two Rapeseed Cultivars during the Early Seedling Stage

Antioxidants ◽

10.3390/antiox10081227 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1227

Author(s):

Ali Mahmoud El-Badri ◽

Maria Batool ◽

Ibrahim A. A. Mohamed ◽

Zongkai Wang ◽

Ahmed Khatab ◽

...

Keyword(s):

Salt Stress ◽

Salinity Stress ◽

Stress Responses ◽

Antioxidant Activities ◽

Tricarboxylic Acid Cycle ◽

Seedling Stage ◽

Plant Performance ◽

Salt Tolerant ◽

Brassica Napus L ◽

Early Seedling

Measuring metabolite patterns and antioxidant ability is vital to understanding the physiological and molecular responses of plants under salinity. A morphological analysis of five rapeseed cultivars showed that Yangyou 9 and Zhongshuang 11 were the most salt-tolerant and -sensitive, respectively. In Yangyou 9, the reactive oxygen species (ROS) level and malondialdehyde (MDA) content were minimized by the activation of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) for scavenging of over-accumulated ROS under salinity stress. Furthermore, Yangyou 9 showed a significantly higher positive correlation with photosynthetic pigments, osmolyte accumulation, and an adjusted Na+/K+ ratio to improve salt tolerance compared to Zhongshuang 11. Out of 332 compounds identified in the metabolic profile, 225 metabolites were filtrated according to p < 0.05, and 47 metabolites responded to salt stress within tolerant and sensitive cultivars during the studied time, whereas 16 and 9 metabolic compounds accumulated during 12 and 24 h, respectively, in Yangyou 9 after being sown in salt treatment, including fatty acids, amino acids, and flavonoids. These metabolites are relevant to metabolic pathways (amino acid, sucrose, flavonoid metabolism, and tricarboxylic acid cycle (TCA), which accumulated as a response to salinity stress. Thus, Yangyou 9, as a tolerant cultivar, showed improved antioxidant enzyme activity and higher metabolite accumulation, which enhances its tolerance against salinity. This work aids in elucidating the essential cellular metabolic changes in response to salt stress in rapeseed cultivars during seed germination. Meanwhile, the identified metabolites can act as biomarkers to characterize plant performance in breeding programs under salt stress. This comprehensive study of the metabolomics and antioxidant activities of Brassica napus L. during the early seedling stage is of great reference value for plant breeders to develop salt-tolerant rapeseed cultivars.

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The Dose-dependent Dual Effects of Corticosterone on Spatial Memory Ability After Traumatic Brain Injury Are Mediated by Two Corticosteroid Receptor Systems

10.21203/rs.3.rs-520614/v1 ◽

2021 ◽

Author(s):

Bin Zhang ◽

Mengshi Yang ◽

Qiongyu Yan ◽

Xiaojian Xu ◽

Fei Niu ◽

...

Keyword(s):

Traumatic Brain Injury ◽

Brain Injury ◽

Spatial Memory ◽

Signaling Pathways ◽

Hippocampal Neurons ◽

High Dose ◽

Short Term ◽

Memory Ability ◽

Neurotoxic Effects ◽

Dose Dependent

Abstract Background: Our recent studies reported the opposite effects of mineralocorticoid receptor (MR) and glucocorticoid receptor (GR) on neuron survival after traumatic brain injury (TBI). However, as a mixed agonist for MR and GR, whether short term use of high-dose endogenous glucocorticoids exerts neurotoxic effects by excessive activation of GR, what is the set-point, and the possible signaling pathways remain unclear. This study examined the dose-dependent dual effects of corticosterone (CORT) on the spatial memory, the survival of hippocampal neurons and the possible receptor-mediated downstream signaling pathways after TBI.Methods: Based on controlled cortical impact (CCI) and CORT treatments, Sprague-Dawley rats (n=168) were randomly divided into the sham, CCI, CCI + CORT1 (0.3 mg/kg), CCI + CORT2 (3 mg/kg), CCI + CORT3 (30 mg/kg), CCI + CORT1 + spirolactone (spirolactone: 50 mg/kg/d), and CCI + CORT3 + RU486 (RU486: 50 mg/kg/d) groups. Brain tissues were collected on postinjury day 3 and processed for histology and western blot analysis.Results: On postinjury day 3, we tested the learning and memory ability, neuronal apoptosis in the hippocampus, activation levels of MR and GR, Bcl-2 family proteins, and apoptosis-related intracellular signaling pathways. We found that different doses of CORT exhibited dual effects on the survival of hippocampal neurons and the spatial memory. Lower doses of CORT (0.3, 3 mg/kg) significantly increased the activation of MR, upregulated the phosphorylation of Akt/CREB/Bad and the Bcl-2 expression, reduced the number of apoptotic neurons, and subsequently improved the spatial memory. In contrast, higher dose of CORT (30 mg/kg) exerted opposite effect by over activating GR, upregulating the expressions of P53/Bax, and inhibiting the Erk/CREB activities. Conclusion: The results suggest that there is a threshold between the neuroprotective and neurotoxic effects of endogenous GC, higher dose of which, even for short-term use, should also be avoided after TBI.

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N6-methyladenosine modification modulate in the heat stress of sheep (Ovis aries)

10.21203/rs.2.9885/v1 ◽

2019 ◽

Author(s):

Zengkui Lu ◽

Huihua Wang ◽

Youji Ma ◽

Mingxing Chu ◽

Kai Quan ◽

...

Keyword(s):

Heat Stress ◽

Signaling Pathways ◽

Stress Responses ◽

Large Scale ◽

Ovis Aries ◽

Stop Codons ◽

Coding Regions ◽

Mrna Methylation ◽

Response To Stress ◽

And Control

Abstract Background: Intensive and large-scale development of the sheep industry and increases in global temperature are increasingly exposing sheep to heat stress. N6-methyladenosine (m6A) mRNA methylation varies in response to stress, and can link external stress with complex transcriptional and post-transcriptional processes. However, no m6A mRNA methylation map has been obtained for sheep, nor is it known what effect this has on regulating heat stress in sheep. Results: A total of 8,306 and 12,958 m6A peaks were detected in heat stress and control groups, respectively, with 2,697 and 5,494 genes associated with each. Peaks were mainly enriched in coding regions and near stop codons with classical RRACH motifs. Methylation levels of heat stress and control sheep were higher near stop codons, although methylation was significantly lower in heat stress sheep. GO revealed that differential m6A-containing genes were mainly enriched in the nucleus and were involved in several stress responses and substance metabolism processes. KEGG pathway analysis found that differential m6A-containing genes were significantly enriched in Rap1, FoxO, MAPK, and other signaling pathways of the stress response, and TGF-beta, AMPK, Wnt, and other signaling pathways involved in fat metabolism. These m6A-modified genes were moderately expressed in both heat stress and control sheep, and the enrichment of m6A modification was significantly negatively correlated with gene expression. Conclusions: Our results showed that m6A mRNA methylation modifications regulate heat stress in sheep, and it also provided a new way for the study of animal response to heat stress.

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Emodin promotes apoptosis of human endometrial cancer through regulating the MAPK and PI3K/ AKT pathways

Open Life Sciences ◽

10.1515/biol-2018-0058 ◽

2019 ◽

Vol 13 (1) ◽

pp. 489-496 ◽

Cited By ~ 2

Author(s):

Jun Jiang ◽

Nanyang Zhou ◽

Pian Ying ◽

Ting Zhang ◽

Ruojia Liang ◽

...

Keyword(s):

Endometrial Cancer ◽

Signaling Pathways ◽

Tumor Development ◽

Mapk Signaling ◽

Dependent Manner ◽

Western Blot Assay ◽

Anti Oxidant ◽

Underlying Mechanisms ◽

Induced Apoptosis ◽

Dose Dependent

AbstractEmodin, a major component of rhubarb, has anti-tumor effects in a variety of cancers, influencing multiple steps of tumor development through modulating several signaling pathways. The aim of this study is to examine the effect of emodin on cell apoptosis and explore the underlying mechanisms in human endometrial cancer cells. Here we report that emodin can inhibit KLE cell proliferation and induce apoptosis in a time- and dose-dependent manner. Western blot assay found that emodin was involved in MAPK and PI3K/Akt signaling pathways. Specifically, emodin significantly suppressed the phosphorylation of AKT, and enhanced the phosphorylation of MAPK pathways. Furthermore, the generation of reactive oxygen species (ROS) was up-regulated in KLE cells upon treatment with emodin, while the anti-oxidant agent N-acetyl cysteine (NAC) can inhibit emodin-induced apoptosis and promote the activation of AKT and Bcl-2. Taken together, we revealed that emodin may induce apoptosis in KLE cells through regulating the PI3K/AKT and MAPK signaling pathways, indicating the importance of emodin as an anti-tumor agent.

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The Impact of Drosophila Awd/NME1/2 Levels on Notch and Wg Signaling Pathways

International Journal of Molecular Sciences ◽

10.3390/ijms21197257 ◽

2020 ◽

Vol 21 (19) ◽

pp. 7257

Author(s):

Giulia Serafini ◽

Giorgia Giordani ◽

Luca Grillini ◽

Davide Andrenacci ◽

Giuseppe Gargiulo ◽

...

Keyword(s):

Cell Death ◽

Notch Signaling ◽

Signaling Pathways ◽

Target Genes ◽

Wing Disc ◽

Amino Terminal ◽

Disc Cells ◽

Function Blocks ◽

The Impact ◽

Dose Dependent

Awd, the Drosophila homologue of NME1/2 metastasis suppressors, plays key roles in many signaling pathways. Mosaic analysis of the null awdJ2A4 allele showed that loss of awd gene function blocks Notch signaling and the expression of its target genes including the Wingless (Wg/Wnt1) morphogen. We also showed that RNA interference (RNAi)-mediated awd silencing (awdi) in larval wing disc leads to chromosomal instability (CIN) and to Jun amino-terminal kinases (JNK)-mediated cell death. Here we show that this cell death is independent of p53 activity. Based on our previous finding showing that forced survival of awdi-CIN cells leads to aneuploidy without the hyperproliferative effect, we investigated the Wg expression in awdi wing disc cells. Interestingly, the Wg protein is expressed in its correct dorso-ventral domain but shows an altered cellular distribution which impairs its signaling. Further, we show that RNAi-mediated knock down of awd in wing discs does not affect Notch signaling. Thus, our analysis of the hypomorphic phenotype arising from awd downregulation uncovers a dose-dependent effect of Awd in Notch and Wg signaling.

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