Ability Of Reactive Oxygen Species Research Articles

Evolutionary studies of the basic helix–loop–helix (bHLH) IVc gene family in plants and the role of AtILR3 in Arabidopsis response to ABA stress

AbstractThe basic helix–loop–helix (bHLH) IVc transcription factors (TFs) play central roles in controlling iron (Fe) homeostasis and biotic stress responses. However, their evolutions and functions in other abiotic stresses are poorly understood. In this study, the IAA‐LEUCINE RESISTANT3 (ILR3) homologs were traced roughly back to before the early origin of land plants and divided into six main clades (Clade A‐F). Further analysis found that the ILR3 orthologs were angiosperm‐specific, suffering from motif‐acquisition events and loose purifying selection. Synteny analysis displayed that the whole genome duplications (WGDs) contributed to the establishment of the IRON DEFICIENCY TOLERANT1 (IDT1, also called bHLH34)/bHLH104 lineage prior to the divergence of angiosperms. Sequence analysis revealed that the ILR3 homologs had some novel and conserved motifs except bHLH and leucine zipper (ZIP) domains. Particularly, Arabidopsis thaliana ILR3 (AtILR3) was a nuclear protein and greatly activated by ABA and CdCl2 stresses. Simultaneously, the molecular and genetic analyses suggested that the AtILR3 acted as a positive regulator in the ABA stress response through enhancing the ability of reactive oxygen species (ROS)‐scavenging, such as the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). The inductively coupled plasma mass spectrometry (ICP‐MS) analyses exhibited that the AtILR3 affected the absorption of nutrient elements, especially iron elements, under ABA stress. Collectively, our findings could shed deep light on the origin and evolution of the plant ILR3s, as well as the functions of the AtILR3 under ABA stress.

PEG-6000 Priming Improves Aged Soybean Seed Vigor via Carbon Metabolism, ROS Scavenging, Hormone Signaling, and Lignin Synthesis Regulation

Seed priming, a valuable seed pretreatment method widely employed in agricultural production, counteracts the decline in seed vigor attributed to aging and deterioration. However, PEG priming effectively enhances the vigor of aged soybean seeds. In this study, “TONGDOU13” soybean seeds were subjected to PEG-6000 priming at varying concentrations (10%, 20%, 30%, 40%) for three different durations (12 h, 24 h, 36 h). The results showed that a 24 h priming with 30% PEG-6000 significantly enhances the vigor of aged soybean seeds. To elucidate the mechanism underlying the heightened vigor resulting from PEG-6000 priming, we employed transcriptome sequencing and physiological–biochemical tests. Transcriptome sequencing analysis showed the significant down-regulation of carbon metabolism-related genes post PEG-6000 priming, which facilitated energetically efficient germination. Five peroxidase-encoding genes displayed significant up-regulation, promoting the conversion of coumaryl alcohol to hydroxy-phenyl lignin, a probable catalyst for augmented seed vigor. SOD and GST genes were significantly up-regulated, enhancing the scavenging ability of reactive oxygen species (ROS). The concurrent up-regulation of brassinolide (BR) and auxin (IAA) signals countered ABA signaling, thereby promoting aged seed germination. Further investigation included the measurements of antioxidant enzyme activity, hormone levels, and lignin content. Notably, primed aged seeds exhibited enhanced ROS scavenging ability, and increased lignin, BR, and IAA contents. Therefore, PEG priming may improve aged soybean seed vigor through the co-regulation of carbon metabolism, ROS scavenging, hormone signaling, and lignin synthesis. This study will be vital for preserving germplasm resources and reutilizing aged soybean seeds.

Genome-wide identification of GTE family proteins in sugarcane (Saccharum spontaneum) reveals that SsGTEL3a confers drought tolerance

The bromodomain is a highly conserved protein domain that specifically binds to acetylated lysine residues in histones, thereby activating transcription of target genes. Although some progress in Global Transcription Factor Group E (GTE) has been achieved in numerous animals and a few plant species, no systematic analysis of GTE gene families has been reported yet in sugarcane. In our study, 37 GTE and GTE-Like (GTEL) genes were characterized in the Saccharum spontaneum. All SsGTE/SsGTEL members were heterogeneously located on all chromosomes of the sugarcane genome and divided into five groups. Transcriptome data showed that SsGTEL3a was expressed at significantly higher levels under drought stress in drought-resistant varieties than in drought-sensitive varieties. Moreover, the overexpression of SsGTEL3a significantly improved the drought tolerance in Arabidopsis through improving the scavenging ability of reactive oxygen species. Additionally, an interaction between ScFAR1 and SsGTEL3a was identified, with ScFAR1 showing a positive response to drought stress in bacterium. In summary, this systematic analysis of GTE gene family in sugarcane and functional research of SsGTEL3a broadened deeper insight into their evolutionary dynamics and functional properties and provided new candidate genes for drought-resistant molecular breeding of sugarcane.

Function identification of miR159a, a positive regulator during poplar resistance to drought stress

Abstract Drought seriously affects the growth and development of plants. MiR159 is a highly conserved and abundant microRNA family that plays a crucial role in plant growth and stress responses. However, studies of its function in woody plants are still lacking. Here, the expression of miR159a was significantly upregulated after drought treatment in poplar, and the overexpression of miR159a (OX159a) significantly reduced the open area of the stomata and improved water-use efficiency in poplar. After drought treatment, OX159a lines had better scavenging ability of reactive oxygen species and damage of the membrane system was less than that in wild-type lines. MYB was the target gene of miR159a, as verified by psRNATarget prediction, RT–qPCR, degradome sequencing, and 5′ rapid amplification of cDNA ends (5′ RACE). Additionally, miR159a–short tandem target mimic suppression (STTM) poplar lines showed increased sensitivity to drought stress. Transcriptomic analysis comparing OX159a lines with wild-type lines revealed upregulation of a series of genes related to response to water deprivation and metabolite synthesis. Moreover, drought-responsive miR172d and miR398 were significantly upregulated and downregulated respectively in OX159a lines. This investigation demonstrated that miR159a played a key role in the tolerance of poplar to drought by reducing stomata open area, increasing the number and total area of xylem vessels, and enhancing water-use efficiency, and provided new insights into the role of plant miR159a and crucial candidate genes for the molecular breeding of trees with tolerance to drought stress.

Improving fresh strawberry shelf life and quality by using the fresh‐keeping paper embedded with oregano essential oil and tea polyphenols

SummaryThe short shelf life of fresh strawberries limits its marketing potential, despite its valuable economic and nutritional benefits. An environmentally friendly fresh‐keeping paper was prepared with oregano essential oil (OEO) and tea polyphenols (TP) and used in the storage of strawberries. Results showed that, during the late storage period, the TP and OEO fresh‐keeping paper treatments reduced malondialdehyde (MDA) content by 29.04% and 34.47%, respectively, compared with the control samples. The treatments also reduced decay incidence, weight loss, epidermal microorganisms and total anthocyanins content (TAC). Furthermore, the treatments reduce polyphenol oxidase (PPO) activity, delay the colour development and maintain better sensory attributes. Notably, OEO fresh‐keeping paper treatment not only increased the titratable acidity (TA) and total soluble solids (TSS) content but also improved the scavenging ability of reactive oxygen species by maintaining high levels of superoxide dismutase (SOD) and catalase (CAT) activity. These results demonstrated that fresh‐keeping paper treatment has the potential to extend the post‐harvest life of strawberries and improve their quality.

A Novel Platform of MOF for Sonodynamic Therapy Advanced Therapies.

Metal-organic frameworks (MOFs) combined with sonodynamic therapy (SDT) have been introduced as a new and efficient treatment method. The critical advantage of SDT is its ability to penetrate deep tissues and concentrate energy on the tumor site to achieve a non-invasive or minimally invasive effect. Using a sonosensitizer to generate reactive oxygen species (ROS) under ultrasound is the primary SDT-related method of killing tumor cells. In the presence of a sonosensitizer, SDT exhibits a more lethal effect on tumors. The fast development of micro/nanotechnology has effectively improved the efficiency of SDT, and MOFs have been broadly evaluated in SDT due to their easy synthesis, easy surface functionalization, high porosity, and high biocompatibility. This article reviews the main mechanism of action of sonodynamic therapy in cancer treatment, and also reviews the applications of MOFs in recent years. The application of MOFs in sonodynamic therapy can effectively improve the targeting ability of SDT and the conversion ability of reactive oxygen species, thus improving their killing ability on cancer cells. This provides new ideas for the application of micro/nano particles in SDT and cancer therapy.

Polyphosphazene nanodrugs for targeting delivery and inflammation responsive release of curcumin to treat acute lung injury by effectively inhibiting cytokine storms

An excessive inflammatory response induced by cytokine storms is the primary reason for the deterioration of patients with acute lung injury (ALI). Though natural polyphenols such as curcumin (CUR) have anti-inflammation activity for ALI treatment, they often have limited efficacy due to their poor solubility in water and oxidising tendency. This study investigates a highly cross-linked polyphosphazene nano-drug (PHCH) developed by copolymerisation of CUR and acid-sensitive units (4-hydroxy-benzoic acid (4-hydroxy-benzylidene)-hydrazide, D-HBD) with hexachlorotripolyphosphonitrile (HCCP) for improved treatment of ALI. PHCH can prolong the blood circulation time and targeted delivery into lung inflammation sites by enhancing CUR's water dispersion and anti-oxidant properties. PHCH also demonstrates the inflammation-responsive release of CUR in an inflammation environment due to the acid-responsive degradation of hydrazine bonds and triphosphonitrile rings in PHCH. Therefore, PHCH has a substantial anti-inflammation activity for ALI treatment by synergistically improving CUR's water-solubility, bioavailability and biocompatibility. As expected, PHCH attenuates the cytokine storm syndrome and alleviates inflammation in the infected cells and tissues by down-regulating several critical inflammatory cytokines (TNF-α, IL-1β, and IL-8). PHCH also decreases the expression of p-p65 and C-Caspase-1, inhibiting NLRP3 inflammasomes and suppressing NF-κB signalling pathways. The administrated mice experiments confirmed that PHCH accumulation was enhanced in lung tissue and showed the efficient scavenging ability of reactive oxygen species (ROS), effectively blocking the cytokine storm and alleviating inflammatory damage in ALI. This smart polyphosphazene nano-drug with targeting delivery property and inflammation-responsive release of curcumin has excellent potential for the clinical treatment of various inflammatory diseases, including ALI.

Continuous NO dual-generation by ZnO nanoparticle conjugated with α-lipoic acid for functional biodegradable vascular stent

Coronary artery diseases are treated with a biodegradable vascular scaffold (BVS) intervention. However, BVS need to be enhanced to avoid post-insertion side effects, which can be done by controlling the nitric oxide (NO) concentration in blood vessels. NO has excellent functions, such as re-endothelialization, inhibition of smooth muscle cells, and prevention of activation and aggregation of platelets, and is essential in maintaining a healthy heart and blood vessels. In this study, a novel nanoparticle with fortified NO-generating ability was synthesized by combining two mechanisms capable of long-term NO production: the decomposition of the NO donor by the redox reaction of zinc oxide and the thiol/disulfide exchange reaction between the NO donor and α-lipoic acid. Next, a poly(L-lactic acid) (PLLA) scaffold containing synthesized nanoparticles was fabricated, and the potent functional recovery ability of unhealthy vessels was demonstrated in vitro and in vivo. The NO generated from scaffolds inhibited platelet adhesion and activation, increased endothelial cell proliferation, and decreased smooth muscle cell proliferation. In addition, the scavenging ability of reactive oxygen species and their inhibition of toxic NO production were investigated. The scaffolds implanted subcutaneously in mice suppressed the inflammatory response and induced healthy blood vessel formation, offering a new tool for designing cardiovascular stents and various biological applications.

Reactive Oxygen Species Produced by 5-Aminolevulinic Acid Photodynamic Therapy in the Treatment of Cancer.

Cancer is the leading cause of death worldwide and several anticancer therapies take advantage of the ability of reactive oxygen species to kill cancer cells. Added to this is the ancient hypothesis that light alone can be used to kill cancer cells. 5-aminolevulinic acid-photodynamic therapy (5-ALA-PDT) is a therapeutic option for a variety of cutaneous and internal malignancies. PDT uses a photosensitizer that, activated by light in the presence of molecule oxygen, forms ROS, which are responsible for the apoptotic activity of the malignant tissues. 5-ALA is usually used as an endogenous pro-photosensitizer because it is converted to Protoporphyrin IX (PpIX), which enters into the process of heme synthesis and contextually becomes a photosensitizer, radiating a red fluorescent light. In cancer cells, the lack of the ferrochelatase enzyme leads to an accumulation of PpIX and consequently to an increased production of ROS. PDT has the benefit of being administered before or after chemotherapy, radiation, or surgery, without impairing the efficacy of these treatment techniques. Furthermore, sensitivity to PDT is unaffected by the negative effects of chemotherapy or radiation. This review focuses on the studies done so far on 5-ALA-PDT and its efficacy in the treatment of various cancer pathologies.

JA-induced TaMPK6 enhanced the freeze tolerance of Arabidopsis thaliana through regulation of ICE-CBF-COR module and antioxidant enzyme system

Mitogen-activated protein kinases (MAPKs) play important roles in the stress response of plants. However, the function of MPK proteins in freeze-resistance in wheat remains unclear. Dongnongdongmai No.1 (Dn1) is a winter wheat variety with a strong freezing resistance at extremely low temperature. In this study, we demonstrated that TaMPK6 is induced by JA signaling and is involved in the modulation of Dn1 freeze resistance. Overexpression of TaMPK6 in Arabidopsis increased the survival rate of plant at −10 ℃. The scavenging ability of reactive oxygen species (ROS) and the expression of cold-responsive genes CBFs and CORs were significantly enhanced in TaMPK6-overexpressed Arabidopsis, suggesting a role of TaMPK6 in activating the ICE-CBF-COR module and antioxidant enzyme system to resist freezing stress. Furthermore, TaMPK6 is localized in the nucleus and TaMPK6 interacts with TaICE41, TaCBF14, and TaMYC2 proteins, the key components in JA signaling and the ICE-CBF-COR pathway. These results suggest that JA-induced TaMPK6 may regulate freezing-resistance in wheat by interacting with the TaICE41, TaCBF14, and TaMYC2 proteins, which in turn enhances the ICE-CBF-COR pathway. Our study revealed the molecular mechanism of TaMPK6 involvement in the cold resistance pathway in winter wheat under cold stress, which provides a basis for enriching the theory of wheat cold resistance.

Electrophysiological microenvironment and site-specific cell behaviors regulated by fibrous aniline trimer-based polyurethanes in bone progressive regeneration

Inspired by the endogenous electric field of natural bone tissue, fibrous aniline trimer (AT)-based polyurethane (FPAT) membranes have been fabricated with good electroactivity through electrospinning, which may serve to restore electrophysiological microenvironment and regulate site-specific cell behaviors to promote osteogenesis. By virtue of the redox activity, the electroactive FPAT membranes exhibited the progressive scavenging ability of reactive oxygen species (ROS) with increasing AT content. Furthermore, a systematic study of specific biomarkers was practiced to draw a comprehensive understanding of the bioelectrical stimulation, including in vitro cell experiments, in vivo RNA-sequencing, subcutaneous implantation, and bone defect repair. Focused on site-specific cell behaviors, both macrophages and mesenchymal stem cells (MSCs)were significantly regulated by the AT-based membranes on electrophysiological microenvironment. For macrophages, the AT-based membranes polarized macrophages to M2 phenotype by efficiently clearing excessive ROS to manipulate the osteoimmune microenvironment in vitro and in vivo. For MSCs, the FPAT membranes scavenged excessive intracellular ROS and elevated intracellular Ca2+ concentration, thereby promoting cell proliferation and driving osteogenesis differentiation. Histology results and gene expression profiles on a rat calvarial bone defect model discovered the efficacy of the AT-based membranes in immunomodulation and osteogenesis. Moreover, the upregulated genes at the RNA level and signaling pathways testified that the electroactive FPAT membranes were strongly involved in regulating macrophage polarization and bone repairing process. This work demonstrated an efficacious therapy of electroactive FPAT membranes from the regulatory mechanism, cellular to tissue levels in bone progressive regeneration, which could provide a legible evaluation system for conductive materials.

SbNAC9 Improves Drought Tolerance by Enhancing Scavenging Ability of Reactive Oxygen Species and Activating Stress-Responsive Genes of Sorghum.

Drought stress severely threatens the yield of cereal crops. Therefore, understanding the molecular mechanism of drought stress response of plants is crucial for developing drought-tolerant cultivars. NAC transcription factors (TFs) play important roles in abiotic stress of plants, but the functions of NAC TFs in sorghum are largely unknown. Here, we characterized a sorghum NAC gene, SbNAC9, and found that SbNAC9 can be highly induced by polyethylene glycol (PEG)-simulated dehydration treatments. We therefore investigated the function of SbNAC9 in drought stress response. Sorghum seedlings overexpressing SbNAC9 showed enhanced drought-stress tolerance with higher chlorophyll content and photochemical efficiency of PSII, stronger root systems, and higher reactive oxygen species (ROS) scavenging capability than wild-type. In contrast, sorghum seedlings with silenced SbNAC9 by virus-induced gene silencing (VIGS) showed weakened drought stress tolerance. Furthermore, SbNAC9 can directly activate a putative peroxidase gene SbC5YQ75 and a putative ABA biosynthesis gene SbNCED3. Silencing SbC5YQ75 and SbNCED3 led to compromised drought tolerance and reduced ABA content of sorghum seedlings, respectively. Therefore, our findings revealed the important role of SbNAC9 in response to drought stress in sorghum and may shed light on genetic improvement of other crop species under drought-stress conditions.

Photoinduced Carbene for Effective Photodynamic Therapy Against Hypoxic Cancer Cells

Photoinduced Carbene for Effective Photodynamic Therapy Against Hypoxic Cancer Cells

Escaping drought: The pectin methylesterase inhibitor gene Slpmei27 can significantly change drought resistance in tomato

Drought stress will lead to a decrease in tomato yield and poor flavour, yield and quality, resulting in economic losses in agricultural production. Mining the key genes regulating tomato drought resistance is of great significance to improve the drought resistance of tomato plants. The cell wall can directly participate in the plant drought stress response as one of the main components of the cell wall, and the regulation of pectin content in plant drought resistance is still unclear. Here, the candidate gene Solyc08g006690 (Slpmei27) was obtained by fine mapping based on genome sequencing technology (BSA-seq) of late-maturing stress-resistant tomato mutants found in the field. Slpmei27 is expressed in the cell wall. The transient silencing of Slpmei27 by VIGS significantly improved the drought resistance of tomato. Meanwhile, Slpmei27 silencing could significantly change the cell wall structure of plants, change the stomatal pass rate, reduce the water loss rate of plants, improve the scavenging ability of reactive oxygen species, change the redox balance in plants, and thus improve the drought resistance of tomato. The promoter region of this gene contains a large number of hormone-response and stress-response binding sites. The promoter region of the Slpmei27 gene in the mutant could lower the expression of downstream genes. Through this study, the mechanism by which Slpmei27 improves tomato drought resistance was revealed, and the relationship between pectin methyl ester metabolism and plant drought resistance was established, providing a theoretical basis for the production of high-quality tomato materials with high drought resistance.

Plant based polyphenol associations with protein: A prospective review

This review discusses the classes of plant polyphenols along with their binding mechanisms with protein molecules. Generally, polyphenols bind in covalent and non-covalent orientations with protein molecules. Their addition to the protein usually results in undesirable flavors and tastes inside the proteins. They also affect the color of the food. Plant polyphenols are found to act in a protective way against cardiovascular disease, neurodegenerative diseases, diabetes, and cancer. In addition to redox activity, their modes of action include the inhibition of key enzymes, modulation of transcription factors or cell receptors, and finally, perturbation of protein aggregates. Dietary polyphenols usually play a key role in protein digestion by forming covalent and non-covalent bonds with proteins. In addition, polyphenols and plant phenolics possess the scavenging ability of reactive oxygen species (ROS), including radical/non-radical oxygen species including HOC•, H2O2, HOCl, 1O2 (singlet oxygen), and oxidatively generated radicals derived from LDL biomolecules such as ROOC• and oligonucleic acids.

Nanozymes-engineered metal–organic frameworks for enhanced microwave thermodynamic therapy in PDX of hepatic carcinoma

Dynamic therapy (DT) has emerged as a promising cancer therapy due to its non-invasive treatment and good spatiotemporal control. However, the efficiency of DT is restricted by several limitations, including insufficient oxygen supply, high expression of pre-tumor factors (e.g., vascular endothelial growth factor, VEGF), and insufficient and relatively weak oxidation ability of reactive oxygen species (ROS) generation. Herein, we propose an in-situ enzyme-like cascade catalysis therapeutic strategy for enhanced MW thermodynamic therapy. The as-prepared nanozymes-engineered metal–organic frameworks (Apatinib@ZIF67@PDA, AZP NCs nanozymes) achieve excellent therapeutic effects in a patient-derived xenograft (PDX) model of hepatic carcinoma. Precisely, after intravenous administration, the ZIF structure of AZP NCs nanozymes is disrupted in the acidic tumor microenvironment, which results in the release of Co (II) and the antiangiogenic agent of Apatinib (AP). Subsequently, Co (II) disproportionates H2O2 into highly oxidizing hydroxyl radicals (•OH) and Co (III). Meanwhile, Co (III) combined with MW can effectively alleviate tumor hypoxia by catalyzing the intratumoral H2O2 to O2, and enhance the generation of ROS. Moreover, the release of AP can downregulate the expression of VEGF, thus effectively inhibiting the tumor angiogenesis after MW thermodynamic therapy. Hence, tumor cells are eliminated completely under the action of MW thermodynamic therapy cooperative combination of AP by AZP NCs nanozymes. This work presents a catalytic strategy for MOF-based nanozymes to improve DT efficiency and provides a new insight for highly efficient anticancer approaches.

EFEK LATIHAN FISIK TERHADAP KADAR MALONDIALDEHID PADA HEWAN MODEL PENUAAN

Aging is a natural process that is characterized by decreased function. In the aging process a decline in the ability of reactive oxygen species. This causes damage to the membrane lipids that cause a decrease in function of the body's organs. Lipid oxidation process in the membrane because free radicals produce lipid peroxidation such as malondialdehyde which is used as a marker of oxidative stress. Regular physical exercise can overcome the negative effects of oxidative stress. To conduct studies on aging, animal models are used. One of the animal models used is the aging induction model by giving D-galactose. Metabolites from d-galactose can induce aging by causing oxidative stress. The purpose of this study was to determine the effect of physical exercise on reducing malondialdehyde levels in an aging animal model induced by D-galactose. This research was experimental in-vivo with a post test only research design. The research sample of 8 weeks old swiss webster mice, consisted of 10 treatment groups. The results of studies on animal models of aging induced D-galactose on malondialdehyde levels after being treated for 6 weeks from the statistical results obtained p value ≥ 0.05 was not significant. However, there was a significant decrease in MDA levels in the D-galactose + physical exercise group

Phytonutrients, Colorant Pigments, Phytochemicals, and Antioxidant Potential of Orphan Leafy Amaranthus Species.

The underutilized Amaranthus leafy vegetables are a unique basis of pigments such as β-cyanins, β-xanthins, and betalains with radical scavenging capacity (RSC). They have abundant phytonutrients and antioxidant components, such as pigments, vitamins, phenolics, and flavonoids. Eight selected genotypes (four genotypes from each species) of underutilized Amaranthus leafy vegetables were evaluated for phytonutrients, pigments, vitamins, phenolics, flavonoids, and antioxidants in a randomized complete block design under ambient field conditions with three replicates. The studied traits showed a wide range of variations across eight genotypes of two species of Amaranthus leafy vegetables. The highest fat, β-xanthins, K, dietary fiber, Mg, β-cyanins, Mn, chlorophyll ab, Zn, TP, TF, betalains, chlorophyll a content, and (RSC) (DPPH) and RSC (ABTS+) were obtained from A. tricolor accessions. Conversely, the highest protein, Cu, carbohydrates, Ca, and chlorophyll b content were obtained from A. lividus accessions. The highest dry matter, carotenoids, Fe, energy, and ash were obtained from A. tricolor and A. lividus. The accession AT2 confirmed the highest vit. C and RSC (DPPH) and RSC (ABTS+); AT5 had the highest TP content; and AT12 had the highest TF content. A. tricolor accessions had high phytochemicals across the two species, such as phytopigments, vitamins, phenolics, antioxidants, and flavonoids, with considerable nutrients and protein. Hence, A. tricolor accessions can be used as high-yielding cultivars comprising ample antioxidants. The correlation study revealed that vitamin C, pigments, flavonoids, β-carotene, and phenolics demonstrated a strong RSC, and showed a substantial contribution to the antioxidant potential (AP) of A. tricolor. The investigation exposed that the accessions displayed a plentiful origin of nutritional values, phytochemicals, and AP with good quenching ability of reactive oxygen species (ROS) that provide enormous prospects for nourishing the mineral-, antioxidant-, and vitamin-threatened community.

The DREB A-5 Transcription Factor ScDREB5 From Syntrichia caninervis Enhanced Salt Tolerance by Regulating Jasmonic Acid Biosynthesis in Transgenic Arabidopsis.

Salinity is a major limiting factor in crop productivity. Dehydration-responsive element-binding protein (DREB) transcription factors have been widely identified in a variety of plants and play important roles in plant stress responses. Studies on DREBs have primarily focused on the A-1 and A-2 DREB groups, while few have focused on the A-5 group. In this study, we concentrated on ScDREB5, an A-5b type DREB gene from the desiccation-tolerant moss Syntrichia caninervis. ScDREB5 is a transcription factor localized to the nucleus that exhibits transactivation activity in yeast. Ectopic ScDREB5 expression in Arabidopsis thaliana increased seed germination and improved seedling tolerance under salt stress. ScDREB5-overexpression transgenic Arabidopsis lines showed lower methane dicarboxylic aldehyde (MDA) and hydrogen peroxide (H2O2) contents, but higher peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) activities compared to wild plants. Moreover, the transcriptional levels of stress marker genes, including RD29B, COR47, LEA6, LEA7, ERD1, P5CS1, and salt overly sensitive (SOS) genes (SOS1, SOS2, and SOS3), were upregulated in the transgenic lines when subjected to salt treatment. Transcriptome and real-time quantitative PCR (RT-qPCR) analyses indicated that transgenic lines were accompanied by an increased expression of jasmonic acid (JA) biosynthesis genes, as well as a higher JA content under salt stress. Our results suggest that ScDREB5 could improve salt tolerance by enhancing the scavenging abilities of reactive oxygen species (ROS), increasing JA content by upregulating JA synthesis gene expression, regulating ion homeostasis by up-regulating stress-related genes, osmotic adjustment, and protein protection, making ScDREB5 a promising candidate gene for crop salt stress breeding.

Near‐infrared chemiluminescent carbon nanogels for oncology imaging and therapy

AbstractCarbon nanogels (CNGs) with dual ability of reactive oxygen species (ROS) imaging and photodynamic therapy have been designed with self‐assembled chemiluminescent carbonized polymer dots (CPDs). With efficient deep‐red/near‐infrared chemiluminescence (CL) emission and distinctive photodynamic capacity, the H2O2‐driven chemiluminescent CNGs are further designed by assembling the polymeric conjugate and CL donors, enabling an in vitro and in vivo ROS bioimaging capability in animal inflammation models and a high‐performance therapy for xenograft tumors. Mechanistically, ROS generated in inflammatory sites or tumor microenvironment can trigger the chemically initiated electron exchange luminescence in the chemical reaction of peroxalate and H2O2, enabling in vivo CL imaging. Meanwhile, part of the excited‐state electrons will transfer to the ambient H2O or dissolved oxygen and in turn lead to the type I and type II photochemical ROS production of hydroxyl radicals or singlet oxygen, endowing the apoptosis of tumor cells and thus enabling cancer therapy. These results open up a new avenue for the design of multifunctional nanomaterials for bioimaging and antienoplastic agents.