Scutellaria baicalensis Georgi flowers is rich in flavonoids resources but not effectively exploited. This study aimed to investigate the anti-aging effects and potential mechanism of Scutellaria ...baicalensis Georgi flowers extract (SFE). The chemical components of the SFE were analyzed by UPLC-MS and the anti-aging effects of SFE were investigated in d-galactose (d-gal) induced aging rats by behavior examination and biochemical indexes, and the potential anti-aging mechanism of SFE were explored by 1H NMR-based liver metabolomics. Chemical composition research showed that 19 flavonoids were identified in SFE, and pharmacological research showed that SFE could significantly ameliorate spatial learning and memory ability. SFE could significantly regulate malondialdehyde (MDA), superoxide dismutase (SOD) and advanced glycation end products (AGEs). It also ameliorated the pathological abnormalities in liver. Additionally, anti-aging mechanism of SFE showed that total of 10 potential biomarkers were found by metabolomics techniques, which involved in 6 metabolic pathways. Among them, SFE could significantly increased the levels of d-glutamine and d-glutamate. Furthermore, the levels of glutamine and glutamate, and the levels of the key amino acids, enzymes and final product in the synthesis process of glutathione (GSH) were quantitatively determined in the liver by commercial kits and enzyme-linked immunosorbent assay. These results indicated that regulation of the glutamine-glutamate metabolic pathway is involved in the anti-aging effect of SFE in d-gal induced aging rats.
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•The chemical components of the Scutellaria baicalensis Georgi flowers extract (SFE) were analyzed.•The anti-aging effect of SFE against d-gal induced aging rats were studied.•The mechanism of SFE in the treatment of aging rats was explored.•The key metabolic pathways or some enzymes significantly associated with aging were quantitatively verified.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Terpenes and terpenoids are key natural compounds for plant defense, development, and composition of plant oil. The synthesis and accumulation of a myriad of volatile terpenoid compounds in these ...plants may dramatically alter the quality and flavor of the oils, which provide great commercial utilization value for oil-producing plants. Terpene synthases (
TPSs
) are important enzymes responsible for terpenic diversity. Investigating the differentiation of the
TPS
gene family could provide valuable theoretical support for the genetic improvement of oil-producing plants. While the origin and function of
TPS
genes have been extensively studied, the exact origin of the initial gene fusion event - it occurred in plants or microbes - remains uncertain. Furthermore, a comprehensive exploration of the
TPS
gene differentiation is still pending. Here, phylogenetic analysis revealed that the fusion of the
TPS
gene likely occurred in the ancestor of land plants, following the acquisition of individual C- and N- terminal domains. Potential mutual transfer of
TPS
genes was observed among microbes and plants. Gene synteny analysis disclosed a differential divergence pattern between TPS-c and TPS-e/f subfamilies involved in primary metabolism and those (TPS-a/b/d/g/h subfamilies) crucial for secondary metabolites. Biosynthetic gene clusters (BGCs) analysis suggested a correlation between lineage divergence and potential natural selection in structuring terpene diversities. This study provides fresh perspectives on the origin and evolution of the
TPS
gene family.
Abstract
Polyploidization plays a key role in plant evolution, but the forces driving the fate of homoeologs in polyploid genomes, i.e., paralogs resulting from a whole-genome duplication (WGD) ...event, remain to be elucidated. Here, we present a chromosome-scale genome assembly of tetraploid scarlet sage (
Salvia splendens
), one of the most diverse ornamental plants. We found evidence for three WGD events following an older WGD event shared by most eudicots (the γ event). A comprehensive, spatiotemporal, genome-wide analysis of homoeologs from the most recent WGD unveiled expression asymmetries, which could be associated with genomic rearrangements, transposable element proximity discrepancies, coding sequence variation, selection pressure, and transcription factor binding site differences. The observed differences between homoeologs may reflect the first step toward sub- and/or neofunctionalization. This assembly provides a powerful tool for understanding WGD and gene and genome evolution and is useful in developing functional genomics and genetic engineering strategies for scarlet sage and other Lamiaceae species.
Based on graph theory, this paper presents a topological heterogeneity and vulnerability analysis of metro networks where transfer constraint is taken into account. The statistical measurements based ...on minimal transfer times are defined, such as betweenness, the shortest path and the average transfer times. Based on above, on the one hand, heterogeneity of network is analyzed by adopting entropy theory; on the other hand, travel efficiency and connectivity based on effective paths are proposed to measure the topological vulnerability of metro network. The feasibility and rationality of the methods described above are verified through the Beijing metro network. The results show that the topological analysis neglecting transfer constraint would underestimate the heterogeneity and vulnerability of the metro network: the topological heterogeneity and vulnerability of Beijing metro network with considering transfer constraint are smaller than without considering transfer constraint; in the case of considering transfer constraint, with the scale expansion of network, travel efficiency and convenience increase, and topological heterogeneity and vulnerability of network decrease, but the connectivity of metro network is more vulnerable to node-based attack.
•Metro network is abstracted as a model transfers constraint is taken into account.•The statistical measurements based on minimal transfer times are defined, such as betweenness and the shortest path.•Travel efficiency and connectivity based on effective paths are proposed to measure the topological vulnerability of metro network.•The feasibility and rationality of the methods are verified through the Beijing metro network.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The decision-making models that are able to deal with complex and dynamic urban intersections are critical for the development of autonomous vehicles. A key challenge in operating autonomous vehicles ...robustly is to accurately detect the trajectories of other participants and to consider safety and efficiency concurrently into interactions between vehicles. In this work, we propose an approach for developing a tactical decision-making model for vehicles which is capable of predicting the trajectories of incoming vehicles and employs the conflict resolution theory to model vehicle interactions. The proposed algorithm can help autonomous vehicles cross intersections safely. Firstly, Gaussian process regression models were trained with the data collected at intersections using subgrade sensors and a retrofit autonomous vehicle to predict the trajectories of incoming vehicles. Then, we proposed a multiobjective optimization problem (MOP) decision-making model based on efficient conflict resolution theory at intersections. After that, a nondominated sorting genetic algorithm (NSGA-II) and deep deterministic policy gradient (DDPG) are employed to select the optimal motions in comparison with each other. Finally, a simulation and verification platform was built based on Matlab/Simulink and PreScan. The reliability and effectiveness of the tactical decision-making model was verified by simulations. The results indicate that DDPG is more reliable and effective than NSGA-II to solve the MOP model, which provides a theoretical basis for the in-depth study of decision-making in a complex and uncertain intersection environment.
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CEKLJ, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
•An underivatized LC–MS/MS method for simultaneous determination of several neurotransmitters of Trp, Phe and Glu metabolism was developed.•The method was independently verified in urine, plasma and ...hippocampus according to FDA guideline for bioanalytical method validation.•The method was applied to determine the concentrations of the neurotransmitters in CUMS-induced depression rats’ hippocampus, plasma and urine.•Tyr, Trp, 5-HT and QUIN levels were significantly altered in CNS and peripheral matrices.•The peripheral transformation of neurotransmitters may be directly or indirectly involved in pathological processes.
Sensitive and comprehensive measurement of systemic metabolites of tryptophan, phenylalanine and glutamate metabolism in biological samples is effective for understanding the pathogenesis of depression and other neurological diseases. Therefore, this study developed an underivatized liquid chromatography tandem mass spectrometry (LC–MS/MS) method for simultaneous monitoring the 3 components of glutamate metabolism in rat hippocampus and 11 components of tryptophan and phenylalanine metabolism in rat hippocampus, plasma and urine, and applied it to investigate their changes in rats induced by chronic unpredictable mild stress (CUMS). The investigated analytes are as follows: tryptophan, serotonin, 5-hydroxyindoleacetic acid, kynurenine, kynurenic acid, xanthurenic acid, 3-hydroxyanthranilic acid, quinolinic acid, phenylalanine, tyrosine, tyramine, glutamate, glutamine and gamma-aminobutyric acid. The method was verified to be sensitive and effective with satisfactory linearity, accuracies in the range of 78.2%–120.4%, and precisions less than 17.8% for all identified analytes. A series of significant changes in CUMS-induced rats can be detected: tryptophan, serotonin and tyrosine levels decreased and quinolinic acid increased in both hippocampus and plasma. In addition, the kynurenine/tryptophan ratios increased in hippocampus and plasma, the kynurenic acid/quinolinic acid ratios of plasma and urine were significantly reduced. These findings demonstrated that the CUMS procedure could lead to the central and peripheral imbalances of tryptophan and phenylalanine metabolism. In conclusion, a LC–MS/MS method for simultaneous measurement of several neurotransmitters in rat hippocampus, plasma and urine was developed and successfully applied to investigation of the central and peripheral changes in CUMS-induced rats. The method would be expected to provide applicability to the study of the mechanisms of depression and other related diseases associated with these neurotransmitters.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Penicillium oxalicum produces an integrated, extracellular cellulase and xylanase system, strictly regulated by several transcription factors. However, the understanding of the regulatory mechanism ...of cellulase and xylanase biosynthesis in
is limited, particularly under solid-state fermentation (SSF) conditions. In our study, deletion of a novel gene,
(
ellulolytic and
ylanolytic
egulator
), resulted in 49.3 to 2,230% enhanced production of cellulase and xylanase, except for 75.0% less xylanase at 2 days, compared with the
parental strain, when cultured on solid medium containing wheat bran plus rice straw for 2 to 4 days after transfer from glucose. In addition, the deletion of
delayed conidiospore formation, leading to 45.1 to 81.8% reduced asexual spore production and altered mycelial accumulation to various extents. Comparative transcriptomics and real-time quantitative reverse transcription-PCR found that CXRD dynamically regulated the expression of major cellulase and xylanase genes and conidiation-regulatory gene
under SSF.
electrophoretic mobility shift assays demonstrated that CXRD bound to the promoter regions of these genes. The core DNA sequence 5'-CYGTSW-3' was identified to be specifically bound by CXRD. These findings will contribute to understanding the molecular mechanism of negative regulation of fungal cellulase and xylanase biosynthesis under SSF.
Application of plant cell wall-degrading enzymes (CWDEs) as catalysts in biorefining of lignocellulosic biomass into bioproducts and biofuels reduces both chemical waste production and carbon footprint. The filamentous fungus
can secrete integrated CWDEs, with potential for industrial application. Solid-state fermentation (SSF), simulating the natural habitat of soil fungi, such as
, is used for CWDE production, but a limited understanding of CWDE biosynthesis hampers the improvement of CWDE yields through synthetic biology. Here, we identified a novel transcription factor CXRD, which negatively regulates the biosynthesis of cellulase and xylanase in
under SSF, providing a potential target for genetic engineering to improve CWDE production.
Resistance traits of plants can be activated both at the damaged site and undamaged parts. Systemic resistance induced by local exogenous abscisic acid (ABA) application alleviated negative effect of ...low water availability on growth performance of clonal plant. However, timing of systemic resistance was poorly understood. Timing of systemic resistance refers to its activation and decay time within clonal network. Clonal fragment of
with four successive ramets (including first-oldest, second-older, third-old and fourth-young ramets) subjected to low water availability (20% soil moisture content) was used to explore effects of local exogenous ABA application on the timing of resistance activation and decay. Systemic resistance activated by local exogenous ABA application after 4 days remained at least 28 days. Compared with control, biomass accumulation of whole clonal fragment, root biomass and ratio of belowground to aboveground biomass significantly increased by local exogenous ABA application after 28 days. It is suggested that rapid activation and delay of resistance response induced by local exogenous ABA application within clonal network may improve fitness of clonal plant subjected to abiotic stress.
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