Excessive rainfall provides a favorable condition for field mold infection of plants, which triggers field mold (FM) stress. If FM stress occurs during the late maturation stage of soybean seed, it ...negatively affects seed yield and quality. To investigate the responses of soybean seed against FM stress and identify the underlying biochemical pathways involved, a greenhouse was equipped with an artificial rain producing system to allow the induction of mold growth on soybean seed. The induced quality changes and stress responses were revealed on the levels of both transcriptome and metabolome. The results showed that soybean seeds produced under FM stress conditions had an abnormal and inferior appearance, and also contained less storage reserves, such as protein and polysaccharide. Transcriptional analysis demonstrated that genes involved in amino acid metabolism, glycolysis, tricarboxylic acid, β-oxidation of fatty acids, and isoflavone biosynthesis were induced by FM stress. These results were supported by a multiple metabolic analysis which exhibited increases in the concentrations of a variety of amino acids, sugars, organic acids, and isoflavones, as well as reductions of several fatty acids. Reprogramming of these metabolic pathways mobilized and consumed stored protein, sugar and fatty acid reserves in the soybean seed in order to meet the energy and substrate demand on the defense system, but led to deterioration of seed quality. In general, FM stress induced catabolism of storage reserves and diminished the quality of soybean seed in the field. This study provides a more profound insight into seed deterioration caused by FM stress.
Microalgae are arguably the most abundant single-celled eukaryotes and are widely distributed in oceans and freshwater lakes. Moreover, microalgae are widely used in biotechnology to produce ...bioenergy and high-value products such as polyunsaturated fatty acids (PUFAs), bioactive peptides, proteins, antioxidants and so on. In general, genetic editing techniques were adapted to increase the production of microalgal metabolites. The main genome editing tools available today include zinc finger nucleases (ZFNs), transcriptional activator-like effector nucleases (TALENs), and the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas nuclease system. Due to its high genome editing efficiency, the CRISPR/Cas system is emerging as the most important genome editing method. In this review, we summarized the available literature on the application of CRISPR/Cas in microalgal genetic engineering, including transformation methods, strategies for the expression of Cas9 and sgRNA, the CRISPR/Cas9-mediated gene knock-in/knock-out strategies, and CRISPR interference expression modification strategies.
Lysine crotonylation (Kcr) is a recently discovered post‐translational modification that potentially regulates multiple biological processes. With an objective to expand the available crotonylation ...datasets, LC‐MS/MS is performed using mouse liver samples under normal physiological conditions to obtain in vivo crotonylome. A label‐free strategy is used and 10 034 Class I (localization probabilities > 0.75) crotonylated sites are identified in 2245 proteins. The KcrE, KcrD, and EKcr motifs are significantly enriched in the crotonylated peptides. The identified crotonylated proteins are mostly enzymes and primarily located in the cytoplasm and nucleus. Functional enrichment analysis based on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes shows that the crotonylated proteins are closely related to the purine‐containing compound metabolic process, ribose phosphate metabolic process, carbon metabolism pathway, ribosome pathway, and a series of metabolism‐associated biological processes. To the best of the authors' knowledge, this research provides the first report on the mouse liver crotonylome. Furthermore, it offers additional evidence that crotonylation exists in non‐histone proteins, and is likely involved in various biological processes. The mass spectrometry proteomics data have been deposited in the ProteomeXchange Consortium with the dataset identifiers PXD019145.
The homeostatic link between oxidative stress and autophagy plays an important role in cellular responses to a wide variety of physiological and pathological conditions. However, the regulatory ...pathway and outcomes remain incompletely understood. Here, we show that reactive oxygen species (ROS) function as signaling molecules that regulate autophagy through ataxia‐telangiectasia mutated (ATM) and cell cycle checkpoint kinase 2 (CHK2), a DNA damage response (DDR) pathway activated during metabolic and hypoxic stress. We report that CHK2 binds to and phosphorylates Beclin 1 at Ser90/Ser93, thereby impairing Beclin 1‐Bcl‐2 autophagy‐regulatory complex formation in a ROS‐dependent fashion. We further demonstrate that CHK2‐mediated autophagy has an unexpected role in reducing ROS levels via the removal of damaged mitochondria, which is required for cell survival under stress conditions. Finally, CHK2−/− mice display aggravated infarct phenotypes and reduced Beclin 1 p‐Ser90/Ser93 in a cerebral stroke model, suggesting an in vivo role of CHK2‐induced autophagy in cell survival. Taken together, these results indicate that the ROS‐ATM‐CHK2‐Beclin 1‐autophagy axis serves as a physiological adaptation pathway that protects cells exposed to pathological conditions from stress‐induced tissue damage.
Synopsis
Whether hypoxia and nutrient starvation are coupled to cellular autophagy remains unclear. Here, DNA damage response kinases ATM and CHK2 are shown to trigger autophagy in response to reactive oxygen species (ROS) accumulation, suggesting a novel physiological adaptation pathway toward metabolic stress.
Depletion of CHK2 or ATM impairs oxidative stress‐induced autophagy in MEFs.
CHK2 binds and phosphorylates Beclin1 at Ser90/Ser93, suppressing Beclin1‐Bcl‐2 autophagy regulatory complex formation.
CHK2‐induced autophagy limits intracellular ROS levels by clearing damaged mitochondria.
CHK2‐induced autophagy protects against cell death and tissue damage following cerebral ischemia.
ROS accumulation activates protective autophagy to prevent stress‐induced tissue damage.
Based on the data of the Chinese A-share listed firms in China Shanghai and Shenzhen Stock Exchange from 2014 to 2021, this article explores the relationship between common institutional investors ...and the quality of management earnings forecasts. The study used the multiple linear regression model and empirically found that common institutional investors positively impact the precision of earnings forecasts. This article also uses graph neural networks to predict the precision of earnings forecasts. Our findings have shown that common institutional investors form external supervision over restricting management to release a wide width of earnings forecasts, which helps to improve the risk warning function of earnings forecasts and promote the sustainable development of information disclosure from management in the Chinese capital market. One of the marginal contributions of this paper is that it enriches the literature related to the economic consequences of common institutional shareholding. Then, the neural network method used to predict the quality of management forecasts enhances the research method of institutional investors and the behavior of management earnings forecasts. Thirdly, this paper calls for strengthening information sharing and circulation among institutional investors to reduce information asymmetry between investors and management.
Ribulose-1,5-bisphosphate carboxylase/oxygenase activase (RCA) is a nuclear gene that encodes a chloroplast protein that plays an important role in photosynthesis. Some reports have indicated that it ...may play a role in acclimation to different abiotic stresses. In this paper, we analyzed the stress-responsive elements in the 2.0 kb 5'-upstream regions of the RCA gene promoter and the primary, secondary and tertiary structure of the protein. We identified some cis-elements of multiple stress-related components in the RCA promoter. Amino acid and evolution analyses showed that the RCA protein had conserved regions between different species; however, the size and type varied. The secondary structures, binding sites and tertiary structures of the RCA proteins were also different. This might reflect the differences in the transcription and translation levels of the two RCA isoforms during adaptation to different abiotic stresses. Although both the transcription and translation levels of RCA isoforms in the rice leaves increased under various stresses, the large isoform was increased more significantly in the chloroplast stroma and thylakoid. It can be concluded that RCA, especially RCAL, is also a multiple responder to abiotic stresses in rice, which provides new insights into RCA functions.
Background and Purpose
The cytokine activin C is mainly expressed in small‐diameter dorsal root ganglion (DRG) neurons and suppresses inflammatory pain. However, the effects of activin C in ...neuropathic pain remain elusive.
Experimental Approach
Male rats and wild‐type and TRPV1 knockout mice with peripheral nerve injury ‐ sciatic nerve axotomy and spinal nerve ligation in rats; chronic constriction injury (CCI) in mice – provided models of chronic neuropathic pain. Ipsilateral lumbar (L)4–5 DRGs were assayed for activin C expression. Chronic neuropathic pain animals were treated with intrathecal or locally pre‐administered activin C or the vehicle. Nociceptive behaviours and pain‐related markers in L4–5 DRGs and spinal cord were evaluated. TRPV1 channel modulation by activin C was measured.
Key Results
Following peripheral nerve injury, expression of activin βC subunit mRNA and activin C protein was markedly up‐regulated in L4–5 DRGs of animals with axotomy, SNL or CCI. Correction added on 26 November 2020, after first online publication: The preceding sentence has been corrected in this current version. Intrathecal activin C dose‐dependently inhibited neuropathic pain in spinal nerve ligated rats. Local pre‐administration of activin C decreased neuropathic pain, macrophage infiltration into ipsilateral L4–5 DRGs and microglial reaction in L4–5 spinal cords of mice with CCI. In rat DRG neurons, activin C enhanced capsaicin‐induced TRPV1 currents. Pre‐treatment with activin C reduced capsaicin‐evoked acute hyperalgesia and normalized capsaicin‐evoked persistent hypothermia in mice. Finally, the analgesic effect of activin C was abolished in TRPV1 knockout mice with CCI.
Conclusion and Implications
Activin C inhibits neuropathic pain by modulating TRPV1 channels, revealing potential analgesic applications in chronic neuropathic pain therapy.
This study aimed to develop a new emulsified film based on konjac glucomannan (KGM)/agar/gum Arabic (GA) incorporating virgin coconut oil (VCO). The effects of VCO on the physical, structural, and ...water barrier properties of the film were investigated. The values of the mechanical and water barrier properties were different with statistical significance (p < 0.05), with VCO contents ranging from 0.1% to 0.6% of the film solid weights. The addition of VCO decreased the tensile strength but effectively increased the elongation at the break of the films. Increased VCO concentrations resulted in decreased water vapor permeability, reduced water swelling, solubility, and adsorption, and increased water contact angle. Compared with cucumber without packaging, packed cucumber with emulsified film showed significantly lower weight loss and firmness reduction during storage up to 12 days at 7 ± 1 °C. Fourier transform infrared spectroscopy results indicated intermolecular hydrogen bonds between KGM, agar, and GA occurred, and X-ray diffraction results suggested that all the films were in the amorphous status. Combining all the above results, the mechanism of the water barrier property improvement was proposed. This study offers an alternative emulsion polysaccharide-based edible film with high potential to be used in cucumber packaging.
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•A novel konjac glucomannan-based emulsified film was fabricated and characterized.•Virgin coconut oil addition greatly improved the water barrier property of the film.•Virgin coconut oil addition can positively influence the EAB of the film.•Effect of emulsified film was assessed on the preservation of cucumber.
Global transcriptional activity increases as oocytes grow and is silenced in fully grown oocytes. Thus, the chromatin configuration varies during oocyte growth, but the molecular mechanisms ...regulating these changes remain to be clarified. Here, we studied a susceptibility gene of polycystic ovary syndrome (PCOS), RPS26, which is a ribosomal protein-encoding gene that is highly expressed in the ovary, but the functions of which remain unknown. Specific knockout of Rps26 in mouse oocytes resulted in retarded follicle development from pre-antral follicles to antral follicles, while the chromatin configurations of the oocytes were arrested at the transition from the non-surrounded nucleolus (NSN) to surrounded nucleolus (SN)-type. As a consequence, all oocytes died by postnatal day 84 resulting in premature ovarian failure (POF). Loss of Rps26 in oocytes led to decreased mRNA transcription and low levels of histone trimethylation on H3K4/H3K9 and DNA methylation at 5-cytosine, high levels of which are required for oocytes to transform from NSN to SN-type. Low protein levels of oocyte-derived growth differentiation factor 9, bone morphogenetic protein 15, and the oocyte-granulosa cell gap junction protein connexin 37 inhibited oocyte growth and retarded follicle development. The disruption of the phosphoinositide 3-kinase/protein kinase B/Forkhead box O-3a pathway contributed to oocyte death and follicle atresia. These results provide genetic clues for the clinical diagnosis of POF, especially in PCOS patients without treatment.
Autophagic degradation of the endoplasmic reticulum (ER-phagy) is triggered by ER stress in diverse organisms. However, molecular mechanisms governing ER stress-induced ER-phagy remain insufficiently ...understood. Here we report that ER stress-induced ER-phagy in the fission yeast Schizosaccharomyces pombe requires Epr1, a soluble Atg8-interacting ER-phagy receptor. Epr1 localizes to the ER through interacting with integral ER membrane proteins VAPs. Bridging an Atg8-VAP association is the main ER-phagy role of Epr1, as it can be bypassed by an artificial Atg8-VAP tether. VAPs contribute to ER-phagy not only by tethering Atg8 to the ER membrane, but also by maintaining the ER-plasma membrane contact. Epr1 is upregulated during ER stress by the unfolded protein response (UPR) regulator Ire1. Loss of Epr1 reduces survival against ER stress. Conversely, increasing Epr1 expression suppresses the ER-phagy defect and ER stress sensitivity of cells lacking Ire1. Our findings expand and deepen the molecular understanding of ER-phagy.
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•Epr1 is a soluble ER-phagy receptor critical for ER stress-induced ER-phagy•The main role of Epr1 is to bridge the association between Atg8 and VAPs•VAP-mediated ER-plasma membrane contact is important for ER stress-induced ER-phagy•UPR regulator Ire1 contributes to ER stress-induced ER-phagy by upregulating Epr1
Zhao et al. show that the fission yeast protein Epr1 confers resistance to ER stress by promoting the autophagic degradation of the ER (ER-phagy). Epr1 acts as a bridging molecule to mediate the association between Atg8 on the autophagic membrane and the integral membrane proteins VAPs on the ER.
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