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Brazilian Journal of Biology = Revista... 2024Cowpea is a leguminous plant belonging to the fabaceae family cultivated in the North and Northeast regions of Brazil, with productive potential. Among the abiotic...
Cowpea is a leguminous plant belonging to the fabaceae family cultivated in the North and Northeast regions of Brazil, with productive potential. Among the abiotic factors, water deficiency is one of the main environmental limitations that influence agricultural production in the world. The objective of this work was to study the relative water content and osmoregulators of cowpea plants subjected to water stress. The experiment was carried out in a greenhouse at the Universidade Federal Rural da Amazônia (UFRA, Belém, PA), cowpea plants BR-17 Gurguéia Vigna unguiculata (L.) Walp were used. The experimental design was completely randomized (DIC) in a 2 × 2 factorial scheme, two water conditions (control and water deficit) and two times of stress (four and six days of water suspension), with 7 replications, totaling 28 experimental units. The water deficit affected plants, causing a reduction in relative water content (69.98%), starch (12.84% in leaves and 23.48% in roots) and carbohydrates (84.34%), and an increase in glycine-betaine, sucrose (114.11% in leaves and 18.71% in roots) and proline (358.86%) at time 2. The relative water content was negatively affected by water conditions, with a decrease in relation to the interaction of the aerial part and the root system. Therefore, greater metabolic responses were noted in plants that were subjected to stress treatment at time 2 (6 days).
Topics: Vigna; Water; Dehydration; Osmoregulation; Betaine
PubMed: 38896729
DOI: 10.1590/1519-6984.281457 -
BioRxiv : the Preprint Server For... Jun 2024How can a single protein domain encode a conformational landscape with multiple stably-folded states, and how do those states interconvert? Here, we use real-time and...
How can a single protein domain encode a conformational landscape with multiple stably-folded states, and how do those states interconvert? Here, we use real-time and relaxation-dispersion NMR to characterize the conformational landscape of the circadian rhythm protein KaiB from . Unique among known natural metamorphic proteins, this KaiB variant spontaneously interconverts between two monomeric states: the "Ground" and "Fold-switched" (FS) state. KaiB in its FS state interacts with multiple binding partners, including the central KaiC protein, to regulate circadian rhythms. We find that KaiB itself takes hours to interconvert between the Ground and FS state, underscoring the ability of a single sequence to encode the slow process needed for function. We reveal the rate-limiting step between the Ground and FS state is the isomerization of three prolines in the fold-switching region by demonstrating interconversion acceleration by the prolyl isomerase CypA. The interconversion proceeds through a "partially disordered" (PD) state, where the C-terminal half becomes disordered while the N-terminal half remains stably folded. We discovered two additional properties of KaiB's landscape. Firstly, the Ground state experiences cold denaturation: at 4°C, the PD state becomes the majorly populated state. Secondly, the Ground state exchanges with a fourth state, the "Enigma" state, on the millisecond timescale. We combine AlphaFold2-based predictions and NMR chemical shift predictions to predict this "Enigma" state is a beta-strand register shift that eases buried charged residues, and support this structure experimentally. These results provide mechanistic insight in how evolution can design a single sequence that achieves specific timing needed for its function.
PubMed: 38895306
DOI: 10.1101/2024.06.03.597139 -
Differential Diagnosis of OKC and SBC on Panoramic Radiographs: Leveraging Deep Learning Algorithms.Diagnostics (Basel, Switzerland) May 2024This study aims to determine whether it can distinguish odontogenic keratocyst (OKC) and simple bone cyst (SBC) based solely on preoperative panoramic radiographs...
This study aims to determine whether it can distinguish odontogenic keratocyst (OKC) and simple bone cyst (SBC) based solely on preoperative panoramic radiographs through a deep learning algorithm. (1) Methods: We conducted a retrospective analysis of patient data from January 2018 to December 2022 at Pusan National University Dental Hospital. This study included 63 cases of OKC confirmed by histological examination after surgical excision and 125 cases of SBC that underwent surgical curettage. All panoramic radiographs were obtained utilizing the Proline XC system (Planmeca Co., Helsinki, Finland), which already had diagnostic data on them. The panoramic images were cut into 299 × 299 cropped sizes and divided into 80% training and 20% validation data sets for 5-fold cross-validation. Inception-ResNet-V2 system was adopted to train for OKC and SBC discrimination. (2) Results: The classification network for diagnostic performance evaluation achieved 0.829 accuracy, 0.800 precision, 0.615 recall, and a 0.695 F1 score. (4) Conclusions: The deep learning algorithm demonstrated notable accuracy in distinguishing OKC from SBC, facilitated by CAM visualization. This progress is expected to become an essential resource for clinicians, improving diagnostic and treatment outcomes.
PubMed: 38893670
DOI: 10.3390/diagnostics14111144 -
International Journal of Molecular... May 2024The NAC family of transcription factors includes no apical meristem (NAM), transcription activator 1/2 (ATAF1/2), and cup-shaped cotyledon (CUC2) proteins, which are...
The NAC family of transcription factors includes no apical meristem (NAM), transcription activator 1/2 (ATAF1/2), and cup-shaped cotyledon (CUC2) proteins, which are unique to plants, contributing significantly to their adaptation to environmental challenges. In the present study, we observed that the PvNAC52 protein is predominantly expressed in the cell membrane, cytoplasm, and nucleus. Overexpression of in strengthened plant resilience to salt, alkali, osmotic, and ABA stresses. PvNAC52 significantly ( < 0.05) reduced the degree of oxidative damage to cell membranes, proline content, and plant water loss by increasing the expression of , , , , , , and . Moreover, the expression of genes associated with abiotic stress responses, such as , , , , , , and , was enhanced by overexpression. A yeast one-hybrid assay showed that PvNAC52 specifically binds to the cis-acting elements ABRE (abscisic acid-responsive elements, ACGTG) within the promoter. This further suggests that PvNAC52 is responsible for the transcriptional modulation of abiotic stress response genes by identifying the core sequence, ACGTG. These findings provide a theoretical foundation for the further analysis of the targeted cis-acting elements and genes downstream of PvNAC52 in the common bean.
Topics: Arabidopsis; Gene Expression Regulation, Plant; Plants, Genetically Modified; Transcription Factors; Abscisic Acid; Stress, Physiological; Phaseolus; Plant Proteins; Osmotic Pressure; Alkalies; Up-Regulation; Promoter Regions, Genetic
PubMed: 38892008
DOI: 10.3390/ijms25115818 -
International Journal of Molecular... May 2024While research has identified several inhibitors of the main protease (Mpro) of SARS-CoV-2, a significant portion of these compounds exhibit reduced activity in the...
Development of a Biosafety Level 1 Cellular Assay for Identifying Small-Molecule Antivirals Targeting the Main Protease of SARS-CoV-2: Evaluation of Cellular Activity of GC376, Boceprevir, Carmofur, Ebselen, and Selenoneine.
While research has identified several inhibitors of the main protease (Mpro) of SARS-CoV-2, a significant portion of these compounds exhibit reduced activity in the presence of reducing agents, raising concerns about their effectiveness in vivo. Furthermore, the conventional biosafety level 3 (BSL-3) for cellular assays using viral particles poses a limitation for the widespread evaluation of Mpro inhibitor efficacy in a cell-based assay. Here, we established a BSL-1 compatible cellular assay to evaluate the in vivo potential of Mpro inhibitors. This assay utilizes mammalian cells expressing a tagged Mpro construct containing N-terminal glutathione -transferase (GST) and C-terminal hemagglutinin (HA) tags and monitors Mpro autodigestion. Using this method, GC376 and boceprevir effectively inhibited Mpro autodigestion, suggesting their potential in vivo activity. Conversely, carmofur and ebselen did not exhibit significant inhibitory effects in this assay. We further investigated the inhibitory potential of selenoneine on Mpro using this approach. Computational analyses of binding energies suggest that noncovalent interactions play a critical role in facilitating the covalent modification of the C145 residue, leading to Mpro inhibition. Our method is straightforward, cost-effective, and readily applicable in standard laboratories, making it accessible to researchers with varying levels of expertise in infectious diseases.
Topics: Antiviral Agents; Humans; SARS-CoV-2; Organoselenium Compounds; Isoindoles; Coronavirus 3C Proteases; Azoles; Proline; Molecular Docking Simulation; Protease Inhibitors; COVID-19 Drug Treatment; COVID-19; HEK293 Cells; Lactams; Leucine; Sulfonic Acids
PubMed: 38891954
DOI: 10.3390/ijms25115767 -
International Journal of Molecular... May 2024Alzheimer's disease (AD) is characterized by the deposition in the brain of senile plaques composed of amyloid-β peptides (Aβs) that increase inflammation. An...
Reduction in Hippocampal Amyloid-β Peptide (Aβ) Content during Glycine-Proline-Glutamate (Gly-Pro-Glu) Co-Administration Is Associated with Changes in Inflammation and Insulin-like Growth Factor (IGF)-I Signaling.
Alzheimer's disease (AD) is characterized by the deposition in the brain of senile plaques composed of amyloid-β peptides (Aβs) that increase inflammation. An endogenous peptide derived from the insulin-like growth factor (IGF)-I, glycine-proline-glutamate (GPE), has IGF-I-sensitizing and neuroprotective actions. Here, we examined the effects of GPE on Aβ levels and hippocampal inflammation generated by the intracerebroventricular infusion of Aβ25-35 for 2 weeks (300 pmol/day) in ovariectomized rats and the signaling-related pathways and levels of Aβ-degrading enzymes associated with these GPE-related effects. GPE prevented the Aβ-induced increase in the phosphorylation of p38 mitogen-activated protein kinase and the reduction in activation of signal transducer and activator of transcription 3, insulin receptor substrate-1, and Akt, as well as on interleukin (IL)-2 and IL-13 levels in the hippocampus. The functionality of somatostatin, measured as the percentage of inhibition of adenylate cyclase activity and the levels of insulin-degrading enzyme, was also preserved by GPE co-treatment. These findings indicate that GPE co-administration may protect from Aβ insult by changing hippocampal cytokine content and somatostatin functionality through regulation of leptin- and IGF-I-signaling pathways that could influence the reduction in Aβ levels through modulation of levels and/or activity of Aβ proteases.
Topics: Animals; Amyloid beta-Peptides; Hippocampus; Rats; Insulin-Like Growth Factor I; Signal Transduction; Female; Oligopeptides; Inflammation; Peptide Fragments; Rats, Wistar; Alzheimer Disease; p38 Mitogen-Activated Protein Kinases; Proto-Oncogene Proteins c-akt; Insulin-Like Peptides
PubMed: 38891902
DOI: 10.3390/ijms25115716 -
International Journal of Molecular... May 2024One aspect of ovarian tumorigenesis which is still poorly understood is the tumor-stroma interaction, which plays a major role in chemoresistance and tumor progression....
One aspect of ovarian tumorigenesis which is still poorly understood is the tumor-stroma interaction, which plays a major role in chemoresistance and tumor progression. Cancer-associated fibroblasts (CAFs), the most abundant stromal cell type in the tumor microenvironment, influence tumor growth, metabolism, metastasis, and response to therapy, making them attractive targets for anti-cancer treatment. Unraveling the mechanisms involved in CAFs activation and maintenance is therefore crucial for the improvement of therapy efficacy. Here, we report that CAFs phenoconversion relies on the glucose-dependent inhibition of autophagy. We show that ovarian cancer cell-conditioning medium induces a metabolic reprogramming towards the CAF-phenotype that requires the autophagy-dependent glycolytic shift. In fact, 2-deoxy-D-glucose (2DG) strongly hampers such phenoconversion and, most importantly, induces the phenoreversion of CAFs into quiescent fibroblasts. Moreover, pharmacological inhibition (by proline) or autophagy gene knockdown (by siBECN1 or siATG7) promotes, while autophagy induction (by either 2DG or rapamycin) counteracts, the metabolic rewiring induced by the ovarian cancer cell secretome. Notably, the nutraceutical resveratrol (RV), known to inhibit glucose metabolism and to induce autophagy, promotes the phenoreversion of CAFs into normal fibroblasts even in the presence of ovarian cancer cell-conditioning medium. Overall, our data support the view of testing autophagy inducers for targeting the tumor-promoting stroma as an adjuvant strategy to improve therapy success rates, especially for tumors with a highly desmoplastic stroma, like ovarian cancer.
Topics: Humans; Female; Autophagy; Cancer-Associated Fibroblasts; Ovarian Neoplasms; Glucose; Cell Line, Tumor; Tumor Microenvironment; Resveratrol; Culture Media, Conditioned; Deoxyglucose; Glycolysis
PubMed: 38891879
DOI: 10.3390/ijms25115691 -
International Journal of Molecular... May 2024AP2/ERF transcription factor genes play an important role in regulating the responses of plants to various abiotic stresses, such as cold, drought, high salinity, and...
AP2/ERF transcription factor genes play an important role in regulating the responses of plants to various abiotic stresses, such as cold, drought, high salinity, and high temperature. However, less is known about the function of oil palm AP2/ERF genes. We previously obtained 172 AP2/ERF genes of oil palm and found that the expression of was significantly up-regulated under salinity, cold, or drought stress conditions. In the present study, the sequence characterization and expression analysis for were conducted, showing that it was transiently over-expressed in L. The results indicated that transgenic tobacco plants over-expressing could have a stronger tolerance to salinity stress than wild-type tobacco plants. Compared with wild-type plants, the over-expression lines showed a significantly higher germination rate, better plant growth, and less chlorophyll damage. In addition, the improved salinity tolerance of transgenic plants was mainly attributed to higher antioxidant enzyme activities, increased proline and soluble sugar content, reduced HO production, and lower MDA accumulation. Furthermore, several stress-related marker genes, including , , , , , , and , were significantly up-regulated in transgenic tobacco plants subjected to salinity stress. Overall, over-expression of the gene significantly enhanced salinity stress tolerance in transgenic tobacco plants. This study lays a foundation for further exploration of the regulatory mechanism of the gene in conferring salinity tolerance in oil palm.
Topics: Nicotiana; Plants, Genetically Modified; Plant Proteins; Salt Tolerance; Gene Expression Regulation, Plant; Salt Stress; Stress, Physiological; Arecaceae; Germination
PubMed: 38891808
DOI: 10.3390/ijms25115621 -
Plants (Basel, Switzerland) Jun 2024Selenium (Se) is crucial for both plants and humans, with plants acting as the main source for human Se intake. In plants, moderate Se enhances growth and increases...
Selenium (Se) is crucial for both plants and humans, with plants acting as the main source for human Se intake. In plants, moderate Se enhances growth and increases stress resistance, whereas excessive Se leads to toxicity. The physiological mechanisms by which Se influences rice seedlings' growth are poorly understood and require additional research. In order to study the effects of selenium stress on rice seedlings, plant phenotype analysis, root scanning, metal ion content determination, physiological response index determination, hormone level determination, quantitative PCR (qPCR), and other methods were used. Our findings indicated that sodium selenite had dual effects on rice seedling growth under hydroponic conditions. At low concentrations, Se treatment promotes rice seedling growth by enhancing biomass, root length, and antioxidant capacity. Conversely, high concentrations of sodium selenite impair and damage rice, as evidenced by leaf yellowing, reduced chlorophyll content, decreased biomass, and stunted growth. Elevated Se levels also significantly affect antioxidase activities and the levels of proline, malondialdehyde, metal ions, and various phytohormones and selenium metabolism, ion transport, and antioxidant genes in rice. The adverse effects of high Se concentrations may directly disrupt protein synthesis or indirectly induce oxidative stress by altering the absorption and synthesis of other compounds. This study aims to elucidate the physiological responses of rice to Se toxicity stress and lay the groundwork for the development of Se-enriched rice varieties.
PubMed: 38891388
DOI: 10.3390/plants13111580 -
Plants (Basel, Switzerland) Jun 2024Salicylic acid (SA) plays a crucial role in regulating plant growth and development and mitigating the negative effects of various stresses, including salinity. In this...
Salicylic acid (SA) plays a crucial role in regulating plant growth and development and mitigating the negative effects of various stresses, including salinity. In this study, the effect of 50 μM SA on the physiological and biochemical parameters of wheat plants under normal and stress conditions was investigated. The results showed that on the 28th day of the growing season, SA pretreatment continued to stimulate the growth of wheat plants. This was evident through an increase in shoot length and leaf area, with the regulation of leaf blade width playing a significant role in this effect. Additionally, SA improved photosynthesis by increasing the content of chlorophyll a (Chl a) and carotenoids (Car), resulting in an increased TAP (total amount of pigments) index in the leaves. Furthermore, SA treatment led to a balanced increase in the levels of reduced glutathione (GSH) and oxidized glutathione (GSSG) in the leaves, accompanied by a slight but significant accumulation of ascorbic acid (ASA), hydrogen peroxide (HO), proline, and the activation of glutathione reductase (GR) and ascorbate peroxidase (APX). Exposure to salt stress for 28 days resulted in a reduction in length and leaf area, photosynthetic pigments, and GSH and ASA content in wheat leaves. It also led to the accumulation of HO and proline and significant activation of GR and APX. However, SA pretreatment exhibited a long-term growth-stimulating and protective effect under stress conditions. It significantly mitigated the negative impacts of salinity on leaf area, photosynthetic pigments, proline accumulation, lipid peroxidation, and HO. Furthermore, SA reduced the salinity-induced depletion of GSH and ASA levels, which was associated with the modulation of GR and APX activities. In small-scale field experiments conducted under natural growing conditions, pre-sowing seed treatment with 50 μM SA improved the main indicators of grain yield and increased the content of essential amino acids in wheat grains. Thus, SA pretreatment can be considered an effective approach for providing prolonged protection to wheat plants under salinity and improving grain yield and quality.
PubMed: 38891377
DOI: 10.3390/plants13111569