Mitochondria-mediated ferroptosis contributes to the inflammatory responses of bovine viral diarrhea virus (BVDV) in vitro.

Bovine viral diarrhea virus (BVDV) belongs to the family Flaviviridae and includes two biotypes in cell culture: cytopathic (CP) or non-cytopathic (NCP) effects. Ferroptosis is a non-apoptotic form of programmed cell death that contributes to inflammatory diseases. However, whether BVDV induces ferroptosis and the role of ferroptosis in viral infection remain unclear. Here, we provide evidence that both CP and NCP BVDV can induce ferroptosis in Madin-Darby bovine kidney cells at similar rate. Mechanistically, biotypes of BVDV infection downregulate cytoplasmic and mitochondrial GPX4 via Nrf2-GPX4 pathway, thereby resulting in lethal lipid peroxidation and promoting ferroptosis. In parallel, BVDV can degrade ferritin heavy chain and mitochondrial ferritin via NCOA4-mediated ferritinophagy to promote the accumulation of Fe2+ and initiate ferroptosis. Importantly, CP BVDV-induced ferroptosis is tightly associated with serious damage of mitochondria and hyperactivation of inflammatory responses. In contrast, mild or unapparent damage of mitochondria and slight inflammatory responses were detected in NCP BVDV-infected cells. More importantly, different mitophagy pathways in response to mitochondria damage by both biotypes of BVDV are involved in inflammatory responses. Overall, this study is the first to show that mitochondria may play key roles in mediating ferroptosis and inflammatory responses induced by biotypes of BVDV in vitro.IMPORTANCEBovine viral diarrhea virus (BVDV) threatens a wide range of domestic and wild cattle population worldwide. BVDV causes great economic loss in cattle industry through its immunosuppression and persistent infection. Despite extensive research, the mechanism underlying the pathogenesis of BVDV remains elusive. Our data provide the first direct evidence that mitochondria-mediated ferroptosis and mitophagy are involved in inflammatory responses in both biotypes of BVDV-infected cells. Importantly, we demonstrate that the different degrees of injury of mitochondria and inflammatory responses may attribute to different mitophagy pathways induced by biotypes of BVDV. Overall, our findings uncover the interaction between BVDV infection and mitochondria-mediated ferroptosis, which shed novel light on the physiological impacts of ferroptosis on the pathogenesis of BVDV infection, and provide a promising therapeutic strategy to treat this important infectious disease with a worldwide distribution.

Disruption of BG14 results in enhanced callose deposition in developing seeds and decreases seed longevity and seed dormancy in Arabidopsis.

Seed longevity is an important trait for agriculture and the conservation of genetic resources. ß-1,3-Glucanases were first recognized as pathogenesis-related proteins involved in plant defense, but their roles in seeds are largely unknown. Here, we report a glycosylphosphatidylinositol-anchored ß-1,3-glucanase, BG14, that degrades callose in seed embryos and functions in seed longevity and dormancy in Arabidopsis. The loss of function of BG14 significantly decreased seed longevity, whereas functional reversion (RE) and overexpression (OE) lines reversed and increased the impaired phenotype, respectively. The loss of function of BG14 enhanced callose deposition in the embryos of mature seeds, confirmed by quantitative determination and the decreased callose degrading ability in bg14. The drop-and-see (DANS) assay revealed that the fluorescence signal in bg14 was significantly lower than that observed in the other three genotypes. BG14 is located on the periphery of the cell wall and can completely merge with callose at the plasmodesmata of epidermal cells. BG14 was highly expressed in developing seeds and was induced by aging and abscisic acid (ABA). The loss of function of BG14 led to a variety of phenotypes related to ABA, including reduced seed dormancy and reduced responses to treatment with ABA or pacolblltrazol, whereas OE lines showed the opposite phenotype. The reduced ABA response is because of the decreased level of ABA and the lowered expression of ABA synthesis genes in bg14. Taken together, this study demonstrated that BG14 is a bona fide BG that mediates callose degradation in the plasmodesmata of embryo cells, transcriptionally influences ABA synthesis genes in developing seeds, and positively affects seed longevity and dormancy in Arabidopsis.

Brain Stimulation of Dorsolateral Prefrontal Cortices Influences Impulsivity in Delay Discounting Choices.

Intertemporal decision-making is pivotal for human interests and health. Recently, studies instructed participants to make intertemporal choices for both themselves and others, but the specific mechanisms are still debated. To address the issue, in the current study, the cost-unneeded conditions (i.e., "Self Immediately - Self Delay" and "Other Immediately - Other Delay" conditions) and the cost-needed conditions (i.e., "Self Immediately - Other Delay" and "Self delay - Other immediately" conditions) were set with the identity of OTHER being a stranger. We manipulated the magnitude of reward (Experiment 1) and disrupted the activation of the dorsolateral prefrontal cortex with repetitive transcranial magnetic stimulation (rTMS; Experiment 2). We found that both the behavioral and rTMS manipulations increased smaller but sooner choice probability via reducing self-control function. The reduced self-control function elicited by rTMS affected both self- and other-related intertemporal choices via increasing the choice preference for SS options, which may help people deeply understand the relationship between self- and other-related intertemporal choices in processing mechanism, especially when the "OTHER" condition is set as a stranger.

Extracellular vesicles derived from PPRV-infected cells enhance signaling lymphocyte activation molecular (SLAM) receptor expression and facilitate virus infection.

Peste des petits ruminants virus (PPRV) is an important pathogen that seriously influences the productivity of small ruminants worldwide. PPRV is lymphotropic in nature and SLAM was identified as the primary receptor for PPRV and other Morbilliviruses. Many viruses have been demonstrated to engage extracellular vesicles (EVs) to facilitate their replication and pathogenesis. Here, we provide evidence that PPRV infection significantly induced the secretion levels of EVs from goat PBMC, and that PPRV-H protein carried in EVs can enhance SLAM receptor expression in the recipient cells via suppressing miR-218, a negative miRNA directly targeting SLAM gene. Importantly, EVs-mediated increased SLAM expression enhances PPRV infectivity as well as the expression of various cytokines related to SLAM signaling pathway in the recipient cells. Moreover, our data reveal that PPRV associate EVs rapidly entry into the recipient cells mainly through macropinocytosis pathway and cooperated with caveolin- and clathrin-mediated endocytosis. Taken together, our findings identify a new strategy by PPRV to enhance virus infection and escape innate immunity by engaging EVs pathway.

Prognostic significance of collagen signatures in pancreatic ductal adenocarcinoma obtained from second-harmonic generation imaging.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) ranks among the deadliest types of cancer, and it will be meaningful to search for new biomarkers with prognostic value to help clinicians tailor therapeutic strategies. METHODS: Here we tried to use an advanced optical imaging technique, multiphoton microscopy (MPM) combining second-harmonic generation (SHG) and two-photon excited fluorescence (TPEF) imaging, for the label-free detection of PDAC tissues from a cohort of 149 patients. An automated image processing method was used to extract collagen features from SHG images and the Kaplan-Meier survival analysis and Cox proportional hazards regression were used to assess the prognostic value of collagen signatures. RESULTS: SHG images clearly show the different characteristics of collagen fibers in tumor microenvironment. We gained eight collagen morphological features, and a Feature-score was derived for each patient by the combination of these features using ridge regression. Statistical analyses reveal that Feature-score is an independent factor, and can predict the overall survival of PDAC patients as well as provide well risk stratification. CONCLUSIONS: SHG imaging technique can potentially be a tool for the accurate diagnosis of PDAC, and this optical biomarker (Feature-score) may help clinicians make more approximate treatment decisions.

Non-cytopathic bovine viral diarrhea virus (BVDV) inhibits innate immune responses via induction of mitophagy.

Bovine viral diarrhea virus (BVDV) belongs to the genus Pestivirus within the family Flaviviridae. Mitophagy plays important roles in virus-host interactions. Here, we provide evidence that non-cytopathic (NCP) BVDV shifts the balance of mitochondrial dynamics toward fission and induces mitophagy to inhibit innate immune responses. Mechanistically, NCP BVDV triggers the translocation of dynamin-related protein (Drp1) to mitochondria and stimulates its phosphorylation at Ser616, leading to mitochondrial fission. In parallel, NCP BVDV-induced complete mitophagy via Parkin-dependent pathway contributes to eliminating damaged mitochondria to inhibit MAVS- and mtDNA-cGAS-mediated innate immunity responses, mtROS-mediated inflammatory responses and apoptosis initiation. Importantly, we demonstrate that the LIR motif of ERNS is essential for mitophagy induction. In conclusion, this study is the first to show that NCP BVDV-induced mitophagy plays a central role in promoting cell survival and inhibiting innate immune responses in vitro.

Association between diabetes mellitus and postoperative urinary retention after cerebral angiography.

AIMS: The aim of this study is to examine the association between diabetes mellitus and postoperative urinary retention on cerebral angiography (including intravascular interventional therapy). METHODS: We collected data on the demographic characteristics and comorbidities, imaging and routine laboratory data, surgical information, and medications of patients who underwent cerebral angiography. Multivariate logistic regression was used to explore the correlation between diabetes and the incidence of postoperative urinary retention. RESULTS: A total of 932 patients were included, with a mean age of 59.7 years (74.1% men). Postoperative urinary retention occurred in 40.8% of the diabetes mellitus group and 30.3% of the group without diabetes. Compared with the group without diabetes, those with diabetes were more likely to experience postoperative urinary retention. Patients with higher glycosylated hemoglobin A1c levels had a higher risk of developing postoperative urinary retention. CONCLUSIONS: Diabetes was independently linked to postoperative urinary retention following cerebral angiography and patients with glycosylated hemoglobin A1c levels > 6% were more likely to experience postoperative urinary retention. Therefore, clinically regulating blood glucose levels may help to reduce the likelihood of postoperative urinary retention after cerebral angiography.

Investigation the mechanism of iron overload-induced colonic inflammation following ferric citrate exposure.

Iron overload occurs due to excessive iron intake compared to the body's demand, leading to iron deposition and impairment of multiple organ functions. Our previous study demonstrated that chronic oral administration of ferric citrate (FC) caused colonic inflammatory injury. However, the precise mechanism underlying this inflammatory response remains unclear. The current study aims to investigate the mechanism by which iron overload induced by FC exposure leads to colonic inflammation. To accomplish this, mice were orally exposed to three different concentrations of FC (71 mg/kg/bw (L), 143 mg/kg/bw (M) and 286 mg/kg/bw (H)) for continuous 16 weeks, with the control group receiving ultrapure water (C). Exposure to FC caused disturbances in the excretory system, altered colonic flora alpha diversity, and enriched pathogenic bacteria, such as Mucispirillum, Helicobacter, Desulfovibrio, and Shigella. These changes led to structural disorders of the colonic flora and an inflammatory response phenotype characterized by inflammatory cells infiltration, atrophy of intestinal glands, and irregular thickening of the intestinal wall. Mechanistic studies revealed that FC-exposure activated the NF-κB signaling pathway by up-regulating TLR4, MyD88, and NF-κB mRNA levels and protein expression. This activation resulted in increased production of pro-inflammatory cytokines, further contributing to the colonic inflammation. Additionally, in vitro experiments in SW480 cells confirmed the activation of NF-κB signaling pathway by FC exposure, consistent with the in vivo findings. The significance of this study lies in its elucidation of the mechanism by which iron overload caused by FC exposure leads to colonic inflammation. By identifying the role of pathogenic bacteria and the NF-κB signaling pathway, this study could potentially offer a crucial theoretical foundation for the research on iron overload, as well as provide valuable insights for clinical iron supplementation.

The perceived controllability of negatively-valenced episodic future thinking modulates delay discounting.

Intertemporal decision-making is important for both economy and physical health. Nevertheless, in daily life, individuals tend to prefer immediate and smaller rewards to delayed and larger rewards, which is known as delay discounting (DD). Episodic future thinking (EFT) has been proven to influence DD. However, there is still no inconsistent conclusion on the effect of negative EFT on DD. Considering the perceived controllability of negative EFT may address the issue (Controllability refers to the extent to which progress and result of an event could be controlled by ourselves). In the current study, we manipulated EFT conditions (baseline, neutral EFT, negative-controllable EFT and negative-uncontrollable EFT), delayed time (i.e. 1 week, 1 month, 3 months, 6 months, 1 year and 3 years) and reward magnitude (small, large). We mainly found that when experiencing negative-uncontrollable EFT compared to negative-controllable EFT in the delayed time of 6 months with large rewards, individuals chose more delayed rewards, suggesting that negative-uncontrollable EFT effectively reduced DD under conditions of both large-magnitude reward and longer delayed time. The current study provides new insight for healthy groups on optimising EFT. In that case, individuals are able to gain long-term benefits in financial management and healthcare.

Dunaliella Ds-26-16 acts as a global regulator to enhance salt tolerance by coordinating multiple responses in Arabidopsis seedlings.

MAIN CONCLUSION: Based on phenotypic, physiological and proteomic analysis, the possible mechanism by which Ds-26-16 regulates salt tolerance in Arabidopsis seedlings was revealed. Functional and mechanistic characterization of salt tolerance genes isolated from natural resources is crucial for their application. In this study, we report the possible mechanism by which Ds-26-16, a gene from Dunaliella, and its point mutation gene EP-5, enhance salt tolerance in Arabidopsis seedlings. Both Ds-26-16 and EP-5 transgenic lines displayed higher seed germination rates, cotyledon-greening rates, soluble sugar contents, decreased relative conductivity and ROS accumulation when germinating under 150 mM NaCl conditions. Comparative proteomic analysis revealed that there were 470 or 391 differentially expressed proteins (DEPs) in Ds-26-16 or EP-5, respectively, compared with the control (3301) under salt stress. The GO and KEGG enrichment analyses showed the DEPs in Ds-26-16 vs. 3301 and EP-5 vs. 3301 were similar and mainly enriched in photosynthesis, regulation of gene expression, carbohydrate metabolism, redox homeostasis, hormonal signal and defense, and regulation of seed germination. Thirty-seven proteins were found to be stably expressed under salt stress due to the expression of Ds-26-16, and eleven of them contain the CCACGT motif which could be bound by the transcription factor in ABA signaling to repress gene transcription. Taken together, we propose that Ds-26-16, as a global regulator, improves salt-tolerance by coordinating stress-induced signal transduction and modulating multiple responses in Arabidopsis seedlings. These results provide valuable information for utilizing natural resources in crop improvement for breeding salt-tolerant crops.

E3 ligase ATL5 positively regulates seed longevity by mediating the degradation of ABT1 in Arabidopsis.

Ubiquitination is a fundamental mechanism regulating the stability of target proteins in eukaryotes; however, the regulatory mechanism in seed longevity remains unknown. Here, we report that an uncharacterized E3 ligase, ARABIDOPSIS TÓXICOS EN LEVADURA 5 (ATL5), positively regulates seed longevity by mediating the degradation of ACTIVATOR OF BASAL TRANSCRIPTION 1 (ABT1) in Arabidopsis. Seeds in which ATL5 was disrupted showed faster accelerated aging than the wild-type, while expressing ATL5 in atl5-2 basically restored the defective phenotype. ATL5 was highly expressed in the embryos of seeds, and its expression could be induced by accelerated aging. A yeast two-hybrid screen identified ABT1 as an ATL5 interacting protein, which was further confirmed by bimolecular fluorescence complementary assay and co-immunoprecipitation analysis. In vitro and in vivo assays showed that ATL5 functions as an E3 ligase and mediates the polyubiquitination and degradation of ABT1. Disruption of ATL5 diminished the degradation of translated ABT1, and the degradation could be induced by seed ageing and occurred in a proteasome-dependent manner. Furthermore, disruption of ABT1 enhanced seed longevity. Taken together, our study reveals that ATL5 promotes the polyubiquitination and degradation of the ABT1 protein posttranslationally and positively regulates seed longevity in Arabidopsis.

DH-GAN: a physics-driven untrained generative adversarial network for holographic imaging.

Digital holography is a 3D imaging technique by emitting a laser beam with a plane wavefront to an object and measuring the intensity of the diffracted waveform, called holograms. The object's 3D shape can be obtained by numerical analysis of the captured holograms and recovering the incurred phase. Recently, deep learning (DL) methods have been used for more accurate holographic processing. However, most supervised methods require large datasets to train the model, which is rarely available in most DH applications due to the scarcity of samples or privacy concerns. A few one-shot DL-based recovery methods exist with no reliance on large datasets of paired images. Still, most of these methods often neglect the underlying physics law that governs wave propagation. These methods offer a black-box operation, which is not explainable, generalizable, and transferrable to other samples and applications. In this work, we propose a new DL architecture based on generative adversarial networks that uses a discriminative network for realizing a semantic measure for reconstruction quality while using a generative network as a function approximator to model the inverse of hologram formation. We impose smoothness on the background part of the recovered image using a progressive masking module powered by simulated annealing to enhance the reconstruction quality. The proposed method exhibits high transferability to similar samples, which facilitates its fast deployment in time-sensitive applications without the need for retraining the network from scratch. The results show a considerable improvement to competitor methods in reconstruction quality (about 5 dB PSNR gain) and robustness to noise (about 50% reduction in PSNR vs noise increase rate).

Cerebral sparganosis in a child with corpus callosum invasion: a case report.

BACKGROUND: Invasion of the corpus callosum by sparganosis is rare in children. After invading the corpus callosum, sparganosis has various migration modes, which can break through the ependyma and enter the ventricles, thus causing secondary migratory brain injury. CASE PRESENTATION: A girl aged 4 years and 7 months presented with left lower limb paralysis for more than 50 days. Blood examination showed that the proportion and absolute number of eosinophils in the peripheral blood were increased. Furthermore, enzyme-linked immunosorbent assay of serum and cerebrospinal fluid samples revealed positivity for IgG and IgM antibodies for sparganosis. Initial magnetic resonance imaging (MRI) revealed ring-like enhancements in the right frontoparietal cortex, subcortical white matter, and splenium of the corpus callosum. Within 2 months, a fourth follow-up MRI showed that the lesion had spread to the left parietal cortex, subcortical white matter, and deep white matter in the right occipital lobe and right ventricular choroid plexus, with left parietal leptomeningeal enhancement. CONCLUSION: Migratory movement is one of the characteristics of cerebral sparganosis. When sparganosis invades the corpus callosum, clinicians should be aware that it may then break through the ependyma and enter the lateral ventricles, leading to secondary migratory brain injury. Short-term follow-up MRI is necessary to evaluate the migration mode of sparganosis and dynamically guide treatment strategies.

Association between the prognostic nutritional index and severe headache or migraine: a population-based study.

PURPOSE: Migraine is a highly prevalent headache disorder, and intake of various nutrients and special diets may improve migraine symptoms. We aimed to clarify the association between nutritional status and migraine. PATIENTS AND METHODS: We collected the data of 1838/8953 (migraineurs/all participants) from the National Health and Nutrition Examination Survey (NHANES) 1999-2004 cycle. We used weighted multivariable linear or logistic regression analyses to study the association between the prognostic nutritional index (PNI) and the occurrence of severe headache or migraine. RESULTS: After adjusting for confounding variables, we found that mild (PNI 45-50) or moderate to severe (PNI <45) malnutrition were associated with higher prevalence of severe headache or migraine (odds ratio [OR] 1.06, 95% confidence interval [CI] 1.00-1.12, P = 0.004; OR 1.07, 95% CI 1.03-1.12, P < 0.001). In addition, we found that those with severe headache or migraine consumed less alcohol, dietary fiber, cholesterol, total folate, vitamin A, riboflavin, vitamin B6, vitamin B12, vitamin C, vitamin K, selenium, potassium, magnesium, and copper, and consumed more caffeine and theobromine than did those without severe headache or migraine. CONCLUSION: The PNI is associated with migraine prevalence, and may thus serve as a predictor of migraine risk and highlights the potential of nutrition-based strategies for migraine prevention and treatment.

Receptor-like kinase HAESA-like 1 positively regulates seed longevity in Arabidopsis.

MAIN CONCLUSION: Based on the phenotypic, physiological and transcriptomic analysis, receptor-like kinase HAESA-like 1 was demonstrated to positively affect seed longevity in Arabidopsis. Seed longevity is very important for both genetic resource conservation and crop production. Receptor-like kinases (RLKs) are widely involved in plant growth, development and stress responses. However, the role of most RLKs, especially in seed longevity, is largely unknown. In this study, we report that Arabidopsis HAESA-like 1 (AtHSL1) positively regulated seed longevity. Disruption of HSL1 significantly decreased the germination rate to 50% at 7 days after cold stratification (DAC), compared with that of the wild type (93.5% at 7 DAC), after accelerated aging treatment. Expression of the HSL1 gene in hsl1 basically restored the defective phenotype (86.3%), while HSL1-overexpressing lines (98.3%) displayed slower accelerated aging than WT (93.5%). GUS staining revealed HSL1 was highly expressed universally, especially in young seedlings, mature seeds and embryos of imbibed seeds, and its expression could be induced by accelerated aging. No difference in the dyeing color and area of mucilage were identified between WT and hsl1. The soluble pectin content also was not different, while the adherent pectin content was significantly increased in hsl1. Global transcriptomics revealed that disruption of HSL1 mainly downregulated genes involved in trehalose synthesis, nucleotide sugar metabolism and protection and repair mechanisms. Therefore, an increase in adherent pectin content and downregulation of genes involved in trehalose synthesis may be the main reasons for decreasing seed longevity owing to disruption of HSL1 in Arabidopsis. Our work provides valuable information for understanding the function and mechanism of a receptor-like kinase, AtHSL1, in seed longevity.

Multifunctional Nanozyme Hydrogel with Mucosal Healing Activity for Single-Dose Ulcerative Colitis Therapy.

Nanozymes are nanomaterials with enzyme-like activities, which have been developed for inflammatory disease therapy by reactive oxygen species (ROS) scavenging. The application of nanozymes in ulcerative colitis (UC) treatment not only inherits the merits of small molecular antioxidants (e.g., 5-aminosalicylic acid) to scavenge ROS but also achieves catalytic recycle instead of stoichiometric consumption. However, current therapies usually ignore the repair of mucosa, the first line of defense, whose damage increases the risk of infections. Herein, a multifunctional nanozyme hydrogel is designed and verified both as an ROS scavenger and a mucosal healing enhancer for UC therapy. The chitosan-coated CeO2 nanozyme (CCNZ) not only possesses excellent ROS-scavenging ability but also exhibits satisfactory antibacterial capacity. After gelation with alginate, the optimized CCNZ1:Alg1.5 nanozyme hydrogel exhibits multiple functions, including inflamed site targeting, supporting cell growth, ROS scavenging, and antibacterial activity, which alleviates UC better than a clinical medication 5-aminosalicylic acid by even a single-dose treatment. This study reveals that a nanozyme providing mucosal healing is promising for UC therapy with excellent potential for clinical application and enriches the nanozyme research of treatment for diseases.

Accuracy of Magnetic Resonance Imaging in Prenatal Diagnosis of Choledochal Cysts: A Single-Center Retrospective Analysis.

Background: The purpose of this study is to evaluate the accuracy of prenatal MRI in diagnosing choledochal cysts (CDC), evaluate the sensitivity and specificity of MRI signs in the diagnosis of fetal CDC, and first compare the trend of size of CC between prenatal and postpartum. Methods: A total of 18 fetal who were diagnosed with CDCs through prenatal MRI were enrolled in the study. We summarized and analyzed the prenatal clinical data and prognosis information of prenatal and postpartum surgery, then compared the sensitivity, specificity, and diagnostic accuracy of various signs of MRI and postpartum MRCP diagnosis of CC. Finally, we tried to compare the earliest prenatal detection of common bile duct cysts with the size of surgery, and calculated the growth rate of common bile duct cysts for the first time. Results: All 18 patients were delivered in our institution. Among these patients, 14 were confirmed with CDCs after postpartum surgery, two patients had CDCs that disappeared, and two patients were confirmed with cystic biliary atresia (CBA) through the Kasai operation. Furthermore, 13 patients with CDCs and two patients with CBA underwent MRCP before the operation, and one patient with CDCs ruptured at birth and underwent ultrasound diagnosis. The sensitivity and diagnostic compliance of prenatal MRI signs for the location were higher when compared to postnatal MRCP (100% vs. 76.9% and 83.3% vs. 66.7%): the cyst was located at the porta hepatis, which was higher than the lowest edge of the liver, and parallel to the hepatoduodenal ligament. Conclusion: Prenatal MRI is higher than that of US for diagnosing CDCs, specifically in identifying the location of the cyst and confirming the origin of the cyst. The length, width, and size of the CDC become slightly bigger in our study.

Extraction of Uranium in Nitric Media with Novel Asymmetric Tetra-Alkylcarbamide.

The use of tetra-alkylcarbamides as novel ligands: N,N-butyl-N',N'-hexylurea (L1: ABHU), and N,N-butyl-N',N'-pentylurea (L2: ABPU), for the solvent extraction and complexation behaviors of uranium(VI) was synthesized and investigated in this study. The effects of HNO3 and NO3- concentrations in the aqueous phase on the distribution ratio of U(VI) were examined. Under 5 mol/L HNO3 concentration, DU reached 5.02 and 4.94 respectively without third-phase formation. During the extraction, slope measurements and IR spectral analysis revealed that the U(VI) complexes are a form of UO2(NO3)2·2L for both ligands. In addition, thermodynamic studies showed that the uranium extraction reaction was a spontaneous exothermic reaction. The deep structural analysis of the complexes was realized with DFT calculation. The bond length, bond properties, and topology of the complexes were discussed in detail to analyze the extraction behavior. This study enriches the coordination chemistry of U(VI) by tetra-alkylcarbamides, which may offer new clues for the design and synthesis of novel ligands for the separation, enrichment, and recovery of uranium in the nuclear fuel cycle.

Os4BGlu14, a monolignol ß-Glucosidase, negatively affects seed longevity by influencing primary metabolism in rice.

KEY MESSAGE: Os4BGlu14, a monolignol ß-glucosidase, plays a negative role in seed longevity by affecting primary metabolism during seed development and aging. Seed longevity is a crucial trait in agriculture and in the conservation of germplasm resources. ß-Glucosidases (BGlus) are multifunctional enzymes that affect plant growth and their adaptation to the environment. The function of rice BGlus in seed longevity, however, remains unknown. We report here that Os4BGlu14, a rice ß-Glucosidase, negatively affected seed longevity during accelerated aging. Os4BGlu14 was highly expressed in rice embryos and induced by accelerated aging. Compared to the wild type, rice lines overexpressing Os4BGlu14 had significantly greater grain length, but smaller grain width and thickness. Overexpressing (OE) lines also showed lower starch but higher glucose contents. After accelerated aging treatment, OE lines displayed a significantly lower germination percentage than the wild type. Additionally, these lines had higher lignin accumulation before and after accelerated aging. Metabolome analysis detected 217 metabolites in untreated and aged rice seeds. Comparison of the differential metabolites between WT and OE5 revealed that ten key metabolites, four of which (e.g., uridine 5'-diphosphoglucose-glucose, UDPG) were increased, while the other six (e.g., γ-aminobutyric acid and methionine) were decreased, might be the crucial factors that lead to seed deterioration. Further analysis confirmed higher UDPG levels and more severe programmed cell death in OE lines than in the wild type. Furthermore, OE lines presented a lower germination rate after abscisic acid and paclobutrazol treatment during germination, compared to the wild type. Our study provides a basis for understanding the function of Os4BGlu14 in seed longevity in rice.

Chloroplastic Os3BGlu6 contributes significantly to cellular ABA pools and impacts drought tolerance and photosynthesis in rice.

Cellular abscisic acid (ABA) concentration is determined by both de novo biosynthesis and recycling via ß-glucosidase(s). However, which rice ß-glucosidase(s) are involved in this process remains unknown. Here, we report on a chloroplastic ß-glucosidase isoenzyme, Os3BGlu6, that functions in ABA recycling in rice. Disruption of Os3BGlu6 in rice resulted in dwarfism, lower ABA content in leaves, drought-sensitivity, lower photosynthesis rate and higher intercellular CO2 concentration. Os3BGlu6 could hydrolyze ABA-GE to ABA in vitro. The reversion and overexpression rice lines restored or increased the drought tolerance as shown by the higher ß-glucosidase activity, ABA concentrations and expressions of ABA- and drought-responsive genes. Drought induced Os3BGlu6 to form dimers, and the degree of polymerization correlated well with the increase in cellular ABA concentrations and drought tolerance in rice. Os3BGlu6 was responsive to drought and ABA treatments, and the protein was localized to the chloroplast. Disruption of Os3BGlu6 resulted in the increased stomatal density and impaired stomatal movement. Transcriptomics revealed that disruption of Os3BGlu6 resulted in chloroplastic oxidative stress and lowered Rubisco activity even under normal conditions. Taken together, these results suggest that chloroplastically localized Os3BGlu6 significantly affects cellular ABA pools, thereby affecting drought tolerance and photosynthesis in rice.