UV-B promotes flavonoid biosynthesis in Ginkgo biloba by inducing the GbHY5-GbMYB1-GbFLS module

Ginkgo biloba(ginkgo)leaves have medicinal value due to their high levels of secondary metabolites,such as flavonoids.We found that the flavonoid content in ginkgo leaves increases significantly at high altitudes(Qinghai-Tibet Plateau).Considering that high UV-B radiation is among the key environmental characteristics of the Qinghai-Tibet Plateau,we carried out simulated UV-B treatments on ginkgo seedlings and found that the flavonoid content of the leaves increased significantly following the treatments.Combined with results from our previous studies,we determined that the transcription factor GbHY5 may play a key role in responses to UV-B radiation.Overexpression of GbHY5 significantly promoted the accumulation of flavonoids in both ginkgo callus and Arabidopsis thaliana.Furthermore,yeast two-hybrid and real-time quantitative PCR showed that GbHY5 promoted the expression of GbMYB1 by interacting with GbMYB1 protein.Overexpression of GbMYB1 in ginkgo callus and A.thaliana also significantly promoted flavonoid biosynthesis.GbFLS encodes a key enzyme in flavonoid biosynthesis,and its promoter has binding elements of GbHY5 and GbMYB1.A dual-luciferase reporter assay indicated that while GbHY5 and GbMYB1 activated the expression of GbFLS individually,their co-expression achieved greater activation.Our analyses reveal the molecular mechanisms by which the UV-B-induced GbHY5-GbMYB1-GbFLS module promotes flavonoid biosynthesis in ginkgo,and they provide insight into the use of UV-B radiation to enhance the flavonoid content of ginkgo leaves.

Cytological, physiological, and transcriptomic analyses of golden leaf coloration in Ginkgo biloba L

Ginkgo biloba is grown worldwide as an ornamental plant for its golden leaf color.However,the regulatory mechanism of leaf coloration in G.biloba remains unclear.Here,we compared G.biloba gold-colored mutant leaves and normal green leaves in cytological,physiological and transcriptomic terms.We found that chloroplasts of the mutant were fewer and smaller,and exhibited ruptured thylakoid membranes,indistinct stromal lamellae and irregularly arranged vesicles.Physiological experiments also showed that the mutant had a lower chlorophyll,lower flavonoid and higher carotenoid contents(especially lutein).We further used transcriptomic sequencing to identify 116 differentially expressed genes(DEGs)and 46 transcription factors(TFs)involved in chloroplast development,chlorophyll metabolism,pigment biosynthesis and photosynthesis.Among these,the chlorophyll biosynthesis-related PPO showed down-regulation,while chlorophyll degradation-related NYC/NOL had up-regulated expression in mutant leaves.Z-ISO,ZDS,and LCYE,which are involved in carotenoid biosynthesis were up-regulated.Quantitative real-time PCR(RT-qPCR)further confirmed the altered expression levels of these genes at three stages.The alteration of PPO and NYC/NOL gene expression might affect chlorophyll biosynthesis and promote degradation of chlorophyll b to chlorophyll a,while the up-regulated genes Z-ISO,ZDS and LCYE enhanced carotenoid accumulation.Consequently,changes in the ratio of carotenoids to chlorophylls were the main factors driving the golden leaf coloration in the mutant G.biloba.

The genome of Medicago polymorpha provides insights into its edibility and nutritional value as a vegetable and forage legume

Medicago polymorpha is a nutritious and palatable forage and vegetable plant that also fixes nitrogen.Here,we reveal the chromosome-scale genome sequence of M.polymorpha using an integrated approach including Illumina,PacBio and Hi-C technologies.We combined PacBio full-length RNA-seq,metabolomic analysis,structural anatomy analysis and related physiological indexes to elucidate the important agronomic traits of M.polymorpha for forage and vegetable usage.The assembled M.polymorpha genome consisted of 457.53Mb with a long scaffold N50 of 57.72Mb,and 92.92%(441.83Mb)of the assembly was assigned to seven pseudochromosomes.Comparative genomic analysis revealed that expansion and contraction of the photosynthesis and lignin biosynthetic gene families,respectively,led to enhancement of nutritious compounds and reduced lignin biosynthesis in M.polymorpha.In addition,we found that several positively selected nitrogen metabolism-related genes were responsible for crude protein biosynthesis.Notably,the metabolomic results revealed that a large number of flavonoids,vitamins,alkaloids,and terpenoids were enriched in M.polymorpha.These results imply that the decreased lignin content but relatively high nutrient content of M.polymorpha enhance its edibility and nutritional value as a forage and vegetable.Our genomic data provide a genetic basis that will accelerate functional genomic and breeding research on M.polymorpha as well as other Medicago and legume plants.

Physiological and Transcriptomic Changes During Autumn Coloration and Senescence in Ginkgo biloba Leaves

Autumn leaf senescence and coloration is a complex process and a striking natural phenomenon.Here,through biology approach integrating transcriptomic analyses in Ginkgo biloba,we determined that the content of chlorophyll decreased during leaf senescence,while carotenoid components increased until late October in the turning stage(TS)and then decreased in the yellow leaf stage(YS).Simultaneously,chlorophyll biosynthesis genes exhibited significantly lower expression levels while chlorophyll degradation genes showed increased expression from the green leaf stage(GS)to YS.However,carotenoid biosynthesis-related genes showed enhanced expression,especially in TS.An analysis of the expression of genes related to senescence demonstrated that the expression levels of most abscisic acid-and jasmonic acid-related genes,autophagy,WRKY,and NAC genes increased,whereas cytoskeleton-,photosynthesis-,and antioxidation-related genes decreased from GS to YS.Furthermore,G.biloba seedlings exogenously treated with abscisic acid,jasmonic acid,or ultraviolet-B radiation all showed obvious color variation and senescence symptoms.We used these exogenously seedlings to further validate the function of several genes involved in chlorophyll biosynthesis and senescence.Taken together,these results contribute to the elucidation of the molecular mechanisms of leaf coloration and senescence in G.biloba as well as in the identification of candidate genes involved in this process.

Cytological and Proteomic Analysis of Ginkgo biloba Pollen Intine

The pollen intine plays important roles in pollen germination and tube growth,but related information in Ginkgo biloba remains unclear.We isolated and obtained de-exined pollen from G.biloba.Using fluorescent probes,we observed the strongest cellulose fluorescence in the pollen intine.De-esterified pectin immunolabeled with JIM5 was present throughout the entire cell wall,whereas esterified pectin recognized by the monoclonal antibody JIM7 was concentrated in some regions.Callose staining with aniline blue was observed across the entire surface of the pollen intine.These results were confirmed by Fourier Transform InfraRed(FTIR)analysis.We also used proteomic approaches to identify different proteins between mature and de-exined pollen(48h after hydration)in vitro.Based on mass spectrometry,de-exined pollen had more proteins than mature pollen,including calmodulin,serine hydroxymethyltransferase,β-galactosidase 6,and class IV chitinase.According to Gene Ontology(GO)analysis,the differentially expressed proteins were mainly associated with transportation,defense reaction,sugar metabolism,energy metabolism,signal transduction,and cell wall formation.These findings suggest that most proteins involved in pollen germination and pollen tube growth are synthesized during pollen hydration,indicating the important role of pollen hydration in the reproductive process of G.Biloba.

Nonlinear Inversion for Complex Resistivity Method Based on QPSO-BP Algorithm

The significant advantage of the complex resistivity method is to reflect the abnormal body through multi-parameters, but its inversion parameters are more than the resistivity tomography method. Therefore, how to effectively invert these spectral parameters has become the focused area of the complex resistivity inversion. An optimized BP neural network (BPNN) approach based on Quantum Particle Swarm Optimization (QPSO) algorithm was presented, which was able to improve global search ability for complex resistivity multi-parameter nonlinear inversion. In the proposed method, the nonlinear weight adjustment strategy and mutation operator were used to enhance the optimization ability of QPSO algorithm. Implementation of proposed QPSO-BPNN was given, the network had 56 hidden neurons in two hidden layers (the first hidden layer has 46 neurons and the second hidden layer has 10 neurons) and it was trained on 48 datasets and tested on another 5 synthetic datasets. The training and test results show that BP neural network optimized by the QPSO algorithm performs better than the BP neural network without initial optimization on the inversion training and test models, and the mean square error distribution is better. At the same time, a double polarized anomalous bodies model was also used to verify the feasibility and effectiveness of the proposed method, the inversion results show that the QPSO-BP algorithm inversion clearly characterizes the anomalous boundaries and is closer to the values of the parameters.

Publisher Correction: Cytological, physiological, and transcriptomic analyses of golden leaf coloration in Ginkgo biloba L

Correction to:Horticulture Research(2018)5:12;https://doi.org/10.1038/s41438-018-0015-4;Article published online 1 March 2018.In the original publication of this article[1]not all authors were listed correctly.In this correction article the full author list is given.The original publication has been corrected.

Application Analysis of Various Geophysical Methods in Volume Calculation of Different Landfills

Garbage disposal has gradually become a key issue faced by environmental governance. What must be controlled in garbage disposal is the calculation of garbage volume. In this paper, according to the different landfill conditions of a landfill in Anhui, including: covering soil, overlying HDPE membrane, overlying concrete, etc., combined with the physical differences between the rock mass and the garbage at the bottom of the landfill. The landfill covered with HDPE membrane adopts the transient electromagnetic method, the landfill covered with soil layer adopts the high-density electrical method, and the landfill covered with concrete adopts the combination of transient electromagnetic method and ground penetrating radar. At the same time, Combines the borehole data to determine that the resistivity value of the interface between the garbage and the soil was 29 Ω⋅m. Finally, the sections of multiple survey lines can accomplish three-dimensional stereoscopic that calculate the distribution and actual volume of the garbage. This method is used to determine the final investment cost.

Influence of crystal-transforming agent on the performance and mechanism ofα-high-strength gypsum prepared from FGD gypsum

This paper investigates the impact of flue gas desulfurization(FGD)gypsum's crystal modifier on the characteristics and microcosmic mechanism ofα-high strength gypsum.The results demonstrate that all three crystal modifiers can convert FGD gypsum toα-high-strength gypsum.Citric acid(CA)has the most significant influence onα-high-strength gypsum,and the preparedα-high-strength gypsum is short columnar,with an aspect ratio in the range of 1-3,and has a faster setting time,a larger specific surface area,and a smaller standard consistency,higher compressive strength,greater surface hardness,and smaller crystal particle size.The initial setting time of theα-high-strength gypsum manufactured with CA crystal modifier was decreased by 36%compared to the blank sample,the final setting time was lowered by 37.5%,and the water consumption of the standard consistency was reduced by 8%.The maximum strength is 32 MPa after 2 h,the absolute dry compressive strength is up to 38 MPa,and the surface hardness is improved by 24.43%.

The Jasmine(Jasminum sambac)Genome Provides Insight into the Biosynthesis of Flower Fragrances and Jasmonates

Jasminum sambac(jasmine flower),a world-renowned plant appreciated for its exceptional flower fragrance,is of cultural and economic importance.However,the genetic basis of its fragrance is largely unknown.Here,we present the first de novo genome assembly of J.sambac with 550.12 Mb(scaffold N50=40.10 Mb)assembled into 13 pseudochromosomes.Terpene synthase(TPS)genes associated with flower fragrance are considerably amplified in the form of gene clusters through tandem duplications in the genome.Gene clusters within the salicylic acid/benzoic acid/theobromine(SABATH)and benzylalcohol O-acetyltransferase/anthocyanin O-hydroxycinnamoyltransferases/anthranilate N-hydroxycinnamoyl/benzoyltransferase/deacetylvindoline 4-O-acetyltransferase(BAHD)superfamilies were identified to be related to the biosynthesis of phenylpropanoid/benzenoid compounds.Several key genes involved in jasmonate biosynthesis were duplicated,causing an increase in copy numbers.In addition,multi-omics analyses identified various aromatic compounds and many genes involved in fragrance biosynthesis pathways.Furthermore,the roles of JsTPS3 in b-ocimene biosynthesis,as well as JsAOC1 and JsAOS in jasmonic acid biosynthesis,were functionally validated.The genome assembled in this study for J.sambac offers a basic genetic resource for studying floral scent and jasmonate biosynthesis,and provides a foundation for functional genomic research and variety improvements in Jasminum.

Spatiotemporal Dynamics of the BRI1 Receptor and its Regulation by Membrane Microdomains in Living Arabidopsis Cells

The major brassinosteroid （BR） receptor of Arabidopsis BRASSINOSTEROID INSENSITIVE1 （BRI1） plays fundamental roles in BR signaling, but the molecular mechanisms underlying the effects of BR on BRI1 internalization and assembly state remain unclear. Here, we applied variable angle total internal reflection fluorescence microscopy and fluorescence cross-correlation spectroscopy to analyze the dynamics of GFP-tagged BRII. We found that, in response to BR, the degree of co-localization of BRI1-GFP with AtFIotl-mCherry increased, and especially BR stimulated the membrane microdomain-associated pathway of BRI1 internalization. We also verified these observations in endocytosis-defective chc2-1 mutants and the AtFIotl amiRNA 15-5 lines. Furthermore, examination of the phosphorylation status of bril-EMS-suppressor 1 and measurement of BR-responsive gene expression revealed that membrane microdomains affect BR signaling. These results suggest that BR promotes the partitioning of BRI1 into functional membrane microdomains to activate BR signaling.

A readily monitored and controllable hydrothermal system for the facile,cost-effective transformation of FGD gypsum to calcium sulfate hemihydrate whiskers

The controllable transformation of flue gas desulfurization(FGD)gypsum to calcium sulfate hemihydrate(HH)whiskers under facile,readily monitored,and cost-effective hydrothermal conditions could play a vital role in the preparation of high quality HH whiskers and improve our understanding of the transformation process.This work assessed the conversion of FGD gypsum to HH whiskers in 5×10^(-4)mol/L H_(2)SO_(4)and 1.5 wt%CuCl_(2)at 120℃while determining the effects of temperature as well as H_(2)SO_(4)and CuCl_(2)concentrations on transformation kinetics.The preparation of HH whiskers was found to involve a solution-mediated transformation from the dihydrate(DH)to theα-HH.This transition was determined to proceed via a dissolution crystallization mechanism,the rate of which was controlled by nucleation and growth of the HH whiskers.An autocatalytic kinetic model was established based on variations in the HH whiskers mole fraction over time,and this model accurately fit the experimental data with R2=0.990.Increasing the temperature or H_(2)SO_(4)concentration accelerated the transformation by modifying the super-saturation and water activity in the reaction solution,while increasing the CuCl_(2)concentration had the opposite effect.The hydrothermal conditions had an important effect on the transformation from FGD gypsum to HH whiskers.

Structural characteristic and formation mechanism of hemihydrate calcium sulfate whiskers prepared using FGD gypsum

Hemihydrate calcium sulfate whiskers(HH-CSWs)were hydrothermally synthesized in a sulfuric acid solution at 120℃ for different holding times(20,40,and 60 min).The phase structures and morphologies were characterized by XRD and SEM,respectively.The XRD pattern of the sample under 60 min was refined via the Rietveld fitting method.The structure models of the HH-CSW sample under a 60-min holding time was established based on Rietveld fitting results.No difference in the positions of diffraction peaks was determined.The as-prepared holding time increased the intensity and aspect ratio of the diffraction peaks of both samples.In the prepared HH-CSW structure,Ca-O polyhedron is a 12-sided polyhedron similar to that in the gypsum structure;the Ca atom is located in two positions in the one-unit cell;the H_(2)O channel along the c-axis similar is O-shaped and bigger than that in hexagonal and monoclinic CaSO_(4)·0.5H_(2)O structures.Therefore,although the prepared HH-CSW crystals’structure are similar to that of the reported hexagonal and monoclinic CaSO_(4)·0.5H_(2)O structures,they are not the same.The formation mechanism of HH-CSW from flue gas desulfurization(FGD)gypsum is discussed based on the analysis of gypsum structure.

Performance analysis of SBAS ephemeris corrections and integrity algorithms in China region

Satellite Based Augmentation Systems(SBASs)improve the positioning accuracy and integrity by broadcasting to the civil aviation community the corrections and integrity parameters.A snapshot algorithm based on the minimum variance estimation is investigated in this study to calculate the satellite clock and orbit corrections.A chi-square test is performed on the remaining errors in the corrected ephemeris to guarantee the integrity.User Differential Range Error(UDRE)and scaling matrix contained in Message Type 28 are derived using the covariance information based on the assumption that one of the reference stations failed.A software package is developed and applied in the real data collected at 26 stations.International GNSS(Global Navigation Satellite System)Service(IGS)precise clock and orbit products are taken as the references to assess the accuracy of corrections.For both Global Positioning System(GPS)and BeiDou Navigation Satellite System(BDS),the range accuracy of 0.10 m can be achieved with the employment of the derived corrections.No obvious performance difference between GPS and BDS is found.UDREs for all visible satellites are generated with the maximum index of 12 and minimum index of 3.The geometric range differences calculated with IGS precise products and broadcast ephemeris are employed to assess the integrity of UDRE.It is found that the UDRE is able to bound the residuals with 99.9%confidence which meet the requirement of aviation users.With ionospheric delay corrected by Global Ionosphere Map(GIM),the positioning accuracy of 0.98 m with GPS corrections and 0.80 m with multi-constellation augmentation can be achieved which indicates a significant improvement of GPS standalone results.