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SUMMARY: Mangroves grow in tropical/subtropical intertidal habitats with extremely high salt tolerance. Trehalose and trehalose‐6‐phosphate (T6P) have an alleviating function against abiotic stress. However, the roles of trehalose in the salt tolerance of salt‐secreting mangrove Avicennia marina is not documented. Here, we found that trehalose was significantly accumulated in A. marina under salt treatment. Furthermore, exogenous trehalose can enhance salt tolerance by promoting the Na+ efflux from leaf salt gland and root to reduce the Na+ content in root and leaf. Subsequently, eighteen trehalose‐6‐phosphate synthase (AmTPS) and 11 trehalose‐6‐phosphate phosphatase (AmTPP) genes were identified from A. marina genome. Abscisic acid (ABA) responsive elements were predicted in AmTPS and AmTPP promoters by cis‐acting elements analysis. We further identified AmTPS9A, as an important positive regulator, that increased the salt tolerance of AmTPS9A‐overexpressing Arabidopsis thaliana by altering the expressions of ion transport genes and mediating Na+ efflux from the roots of transgenic A. thaliana under NaCl treatments. In addition, we also found that ABA could promote the accumulation of trehalose, and the application of exogenous trehalose significantly promoted the biosynthesis of ABA in both roots and leaves of A. marina. Ultimately, we confirmed that AmABF2 directly binds to the AmTPS9A promoter in vitro and in vivo. Taken together, we speculated that there was a positive feedback loop between trehalose and ABA in regulating the salt tolerance of A. marina. These findings provide new understanding to the salt tolerance of A. marina in adapting to high saline environment at trehalose and ABA aspects. Significance Statement: We identified an important salt‐tolerant gene (AmTPS9A) in mangrove Avicennia marina and proposed a hypothesized model in which ABA and trehalose synergistically regulate salt tolerance in A. marina. Our study provides new insights into the salt tolerance of mangrove A. marina at the aspect of the trehalose pathway. [ABSTRACT FROM AUTHOR]

Mangroves perform a crucial ecological role along the tropical and subtropical coastal intertidal zone where salinity fluctuation occurs frequently. However, the differential responses of mangrove plant at the combined transcriptome and metabolome level to variable salinity are not well documented. In this study, we used Avicennia marina (Forssk.) Vierh. a pioneer species of mangrove wetlands and one of the most salt-tolerant mangroves, to investigate the differential salt tolerance mechanisms under low and high salinity using inductively coupled plasma-mass spectrometry, transcriptomic and metabolomic analysis. The results showed that HAK8 was up-regulated and transported K+ into the roots under low salinity. However, under high salinity, AKT1 and NHX2 were strongly induced, which indicated the transport of K+ and Na+ compartmentalization to maintain ion homeostasis. In addition, A. marina tolerates low salinity by up-regulating ABA signaling pathway and accumulating more mannitol, unsaturated fatty acids, amino acids' and L-ascorbic acid in the roots. Under high salinity, A. marina undergoes a more drastic metabolic network rearrangement in the roots, such as more L-ascorbic acid and oxiglutatione were up-regulated, while carbohydrates, lipids and amino acids were down-regulated in the roots, and, finally, glycolysis and TCA cycle were promoted to provide more energy to improve salt tolerance. Our findings suggest that the major salt tolerance traits in A. marina can be attributed to complex regulatory and signaling mechanisms, and show significant differences between low and high salinity. [ABSTRACT FROM AUTHOR]

Salt secretion is an important strategy used by the mangrove plant Aegiceras corniculatum to adapt to the coastal intertidal environment. However, the structural, developmental and functional analyses on the leaf salt glands, particularly the salt secretion mechanism, are not well documented. In this study, we investigated the structural, developmental and degenerative characteristics and the salt secretion mechanisms of salt glands to further elucidate the mechanisms of salt tolerance of A. corniculatum. The results showed that the salt gland cells have a large number of mitochondria and vesicles, and plenty of plasmodesmata as well, while chloroplasts were found in the collecting cells. The salt glands developed early and began to differentiate at the leaf primordium stage. We observed and defined three stages of salt gland degradation for the first time in A. corniculatum , where the secretory cells gradually twisted and wrinkled inward and collapsed downward as the salt gland degeneration increased and the intensity of salt gland autofluorescence gradually diminished. In addition, we found that the salt secretion rate of the salt glands increased when the treated concentration of NaCl increased, reaching the maximum at 400 mM NaCl. The salt-secreting capacity of the salt glands of the adaxial epidermis is significantly greater than that of the abaxial epidermis. The real-time quantitative PCR results indicate that SAD2 , TTG1 , GL2 and RBR1 may be involved in regulating the development of the salt glands of A. corniculatum. Moreover, Na+/H+ antiporter, H+-ATPase, K+ channel and Cl− channel may play important roles in the salt secretion of salt glands. In sum mary, this study strengthens the understanding of the structural, developmental and degenerative patterns of salt glands and salt secretion mechanisms in mangrove recretohalophyte A. corniculatum , providing an important reference for further studies at the molecular level. [ABSTRACT FROM AUTHOR]

We have previously demonstrated that peptide fragments of human serum albumin can be developed into potential renal targeting drug carriers. However, the interactions of these peptide fragments with red blood cells and plasma components are not evaluated well and there is yet no report on the evaluation of the hemocompatibility of peptide fragments. In this study, three kinds of peptide fragments were prepared and identified by amino acid analysis, and the blood compatibility of the peptide fragments was investigated by measuring blood coagulation, platelet and complement activation and hemolysis activity. Results indicated that all the peptide fragments prepared were highly hemocompatible without causing any clot formation, red blood cell aggregation or immune response. In addition, data from the cytotoxicity assay using HeLa cells and Madin-Darby canine kidney cells suggested that these peptide fragments do not induce toxicity towards either cell lines at concentrations up to 5 mg/ml. Therefore, it can be concluded that peptide fragments exhibit good hemocompatibility with no unwanted effect on the viability of renal cells, preliminarily demonstrating that it is safe to use peptide fragments as renal targeting drug carriers. [ABSTRACT FROM AUTHOR]

Background and Aims: Przewalski's horses have been imported from the western zoos to China since 1985. Yet the genetic diversity in China's populations has not been studied, thus lacking of such knowledge inevitably affects this population's management. The aim of this study was to assess genetic diversity in Chinese population of Przewalski's horses via mitochondrial DNA (mtDNA) control region and pedigree analysis. Materials and methods: Two captive and one reintroduced populations were examined based on mitochondrial DNA control region variation via fecal sampling from 2010 to 2012, together with pedigree analysis. Results: Amplification success rates of fecal mtDNA were as high as 96.2% (93.8%-100%), and were higher for sample in winter than in summer and autumn. Two haplotypes were identified and shared among three populations, but the proportion of individuals with each haplotype varied among the three populations ( FST = 0.10874, p = 0.00978). Haplotype diversity in the released population (0.153) was much lower than that in the two captive populations (0.4011 and 0.4966), in accordance with the direction of increase in probability of identity at the dam lines. Conclusion: Future concerns in Przewalski's horse population management should emphasize on strict reproduction control to minimize inbreeding in captivity, followed by long-term genetic diversity guidelines and non-invasive monitoring in the reintroduction programmes. [ABSTRACT FROM AUTHOR]

Trehalose has an important function for alleviating various abiotic stress in plants. Nevertheless, the functional and evolutionary characteristics of trehalose biosynthesis genes in mangrove plants is not documented. Here, using typical mangrove Avicennia marina, we found the trehalose content decreased in the roots and leaves and T6P increased significantly in the leaves under tidal submergence. Then, the basic physicochemical properties and gene structure of trehalose biosynthesis genes (AmTPS and AmTPP), and the conserved domain and motifs of AmTPS and AmTPP proteins were analyzed. The collinearity analysis and Ka/Ks values indicated that AmTPS and AmTPP are evolutionarily conserved. Tissue-specific expression profiling showed that most AmTPS and AmTPP genes have tissue specificity. RNA-Seq analysis showed that five AmTPS genes were markedly up-regulated in A. marina treated with tidal submergence. Subcellular localization analysis revealed three genes including AmTPS10B, AmTPS11A and AmTPS11C out of these five up-regulated AmTPS genes work in plasma membrane, cytoplasm and nucleus. Finally, integrative analysis of bioinformatics and RNA-Seq analysis were performed to excavate transcription factors that may regulate AmTPS and AmTPP genes in A. marina response to submergence. Taken together, these findings provide new insights into the response to tidal submergence in A. marina at the aspect of trehalose., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Hai-Lei Zheng reports financial support was provided by National Natural Science Foundation of China. Hai-Lei Zheng reports financial support was provided by National Key Research and Development Program of China. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

No systematic research has been reported on the correlation between different ecological factors and the effective component content, flower, and leaf traits of Epimedium pubescens. In this study, 21 kinds of E. pubescens in different regions were investigated, and the content of two effective components of icariin(I) and Epimedin C(C), as well as six leaf traits and 12 flower traits were determined. The correlation between 11 ecological factors and the above traits in different regions for five consecutive years was explored. The results showed that no significant correlation was observed between the ecological factors and the total content of two effective components(I+C) of E. pubescens. Latitude and temperature(including annual average temperature, annual average minimum temperature, and soil temperature of each soil layer) were significantly positively and negatively correlated with the ratio of the content of the two effective components(C/I)(P<0.01), respectively. There was a significant correlation between ecological factors and flower traits, and the annual average soil temperature of each soil layer, annual average temperature, and annual average minimum temperature were significantly correlated with most flower traits in multiple years(P<0.01). However, a weak correlation between ecological factors and leaf traits was detected. A significant positive correlation of the annual average soil temperature of each soil layer and annual average humidity(P<0.01) with the width of nutrient leaf in only a few years was detected. Therefore, it was concluded that the total content of effective components of E. pubescens was determined by genetics, with a slight influence of ecological factors. The annual average temperature, annual average minimum temperature, and soil temperature of each soil layer were the ecological factors that had the most significant impact on flower traits, which showed significant differences in different regions, and similar results were not found in leaf traits. Overall, this study systematically conducted a correlation analysis between ecological factors and the effective components, as well as flower and leaf traits, providing guidance for the quality improvement, introduction, and domestication of E. pubescens.

Epimedii Folium is a well-known Chinese herbal medicine with the effect of nourishing kidney and strengthening Yang. Its main active ingredients are flavonoids. In this study, 60 samples of Epimedium sagittatum were collected for the determination of total flavonoids(TF) including the total amount of epimedin A, epimedin B, epimedin C, and icariin(abbreviated as ABCI) specified in the Chinese Pharmacopoeia as well as rhamnosylicariside Ⅱ and icariside Ⅱ. The calibration parameters of "first derivativemultiva-riate scattering correction in 1 900-650 cm~(-1) band(4-point smoothing)" and "first derivativestandard normal variable correction in 4 000-650 cm~(-1) full band(4-point smoothing)" were confirmed respectively. The quantitative model was established via Fourier infrared spectroscopy plus attenuated total reflection(FTIR-ATR) accessory combined with partial least squares(PLS) method and then used to predict the flavonoid content of 11 validation sets. The average prediction accuracy for ABCI in calibration set and validation set was 98.985% and 96.087%, respectively. The average prediction accuracy for TF in calibration set and validation set was 98.998% and 94.771%, respectively. These results indicated that FTIR-ATR combined with PLS model could be used for rapid prediction of flavonoid content in E. sagittatum, with the prediction accuracy above 94.7%. The establishment of this method provides a new solution for the detection of a large number of E. sagittatum samples.

In this study, 10 PA-type Perilla germplasms were selected to detect the content of two phenolic acids, i.e., rosmarinic acid(RA) and caffeic acid(CA), and six flavonoids, including scutellarin-7-O-diglucuronoside(SDG), luteolin-7-O-diglucuronoside(LDG), apigenin-7-O-diglucuronoside(ADG), scutellarin-7-O-glucuroside(SG), luteolin-7-O-glucuroside(LG), and apigenin-7-O-glucuroside(AG) in leaves, stems, and fruits. The total content of phenolic acids and flavonoids in leaves was 3.991-12.028 mg·g~(-1) and 12.309-25.071 mg·g~(-1), respectively, which was much higher than that in stems(0.586-2.015 mg·g~(-1) and 0.879-1.413 mg·g~(-1), respectively) and fruits(0.004-2.222 mg·g~(-1) and 0.651-1.936 mg·g~(-1), respectively). RA was detected in five fruit samples, and RA content between leaves and fruits showed a significant negative correlation in the other five samples. For flavonoids, only LG and LDG could be detected in stems, and SG and SDG were not detected in fruits, while other flavonoids were not detected in some samples. The content of total flavonoids and LG in leaves and fruits was significantly positively correlated, and the content of LG in stems and fruits was significantly positively correlated. In 10 stem samples, seven met the standard that the content of RA in the stem should be not less than 0.1% specified in the Chinese Pharmacopoeia(2020 edition). Only one fruit sample reached the standard of RA content in the fruit not less than 0.25% specified in the Chinese Pharmacopoeia.

During their lifetimes, plants are exposed to different abiotic stress factors eliciting various physiological responses and triggering important defense processes. For UV-B radiation responses in forest trees, the genetics and molecular regulation remain to be elucidated. Here, we exposed Pinus tabuliformis Carr., a major conifer from northern China, to short-term high-intensity UV-B and employed a systems biology approach to characterize the early physiological processes and the hierarchical gene regulation, which revealed a temporal transition from primary to secondary metabolism, the buildup of enhanced antioxidant capacity and stress-signaling activation. Our findings showed that photosynthesis and biosynthesis of photosynthetic pigments were inhibited, while flavonoids and their related derivates biosynthesis, as well as glutathione and glutathione S-transferase mediated antioxidant processes, were enhanced. Likewise, stress-related phytohormones (jasmonic acid, salicylic acid and ethylene), kinase and reactive oxygen species signal transduction pathways were activated. Biological processes regulated by auxin and karrikin were, for the first time, found to be involved in plant defense against UV-B by promoting the biosynthesis of flavonoids and the improvement of antioxidant capacity in our research system. Our work evaluated the physiological and transcriptome perturbations in a conifer's response to UV-B, and generally, highlighted the necessity of a systems biology approach in addressing plant stress biology., (© The Author(s) 2021. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permission@oup.com.)

In this study, the growth index including plant height, compound leaf area, specific leaf area, leaf water content, number of branches, and leaf biomass per plant and the icariin flavonoids such as epimedin A, epimedin B, epimedin C and icariin of Epimedium pseudowushanense were determined on 30 d and 60 d under light intensity(18.2±2.5) μmol·m~(-2)·s~(-1)(L1) and(90.9 ±2.5) μmol·m~(-2)·s~(-1)(L2), and white light as control, red light, blue light and yellow light were used as three light quality treatments, to study the effect of light quality on the growth and flavonoids accumulation of E. pseudowushanense. The E. pseudowushanense was sui-table for growth under L1 light intensity, the blue light treatment significantly reduced the leaf area, but had little effect on the stem height, the red light treatment and the yellow light treatment had no obvious effect on the stem height and leaf area, but the yellow light treatment significantly increased the germination of new branches, and had a sustained promoting effect, and the biomass was significantly higher than the white light treatment at 60 d. The content of icariin flavonoids in red light, blue light and yellow light treatment was higher than that in white light treatment at 30 d and 60 d under L1 light intensity, while yellow light treatment promoted the synthesis of icariin flavonoids to the largest extent, which was 1.8 and 1.9 times of white light treatment(30 d and 60 d).Under L2 light intensity, the effect of strong light on promoting stem germination became the main factor, while the yellow light treatment showed no significant effect on promoting stem germination, and the red light treatment exhibited a significant effect on reducing leaf area. Icariin flavonoids under red light, blue light and yellow light treatment were all lower than that under white light treatment, that is, the effect of white light treatment on the synthesis of icariin flavonoids is better than red light, blue light and yellow light treatment. When the time of strong light treatment was longer, the degradation range of icariin flavonoids in other light treatment appeared, while red light treatment promotes the synthesis of icariin flavonoids. Therefore, the influence of light quality on E. pseudowushanense is quite different under different light intensity, no matter from growth index or flavonoid content index. The results support that the biomass and icariin flavonoid content can be increased by providing appropriate red and yellow light.

Background: Malania oleifera, a member of the Olacaceae family, is an IUCN red listed tree, endemic and restricted to the Karst region of southwest China. This tree's seed is valued for its high content of precious fatty acids (especially nervonic acid). However, studies on its genetic makeup and fatty acid biogenesis are severely hampered by a lack of molecular and genetic tools., Findings: We generated 51 Gb and 135 Gb of raw DNA sequences, using Pacific Biosciences (PacBio) single-molecule real-time and 10× Genomics sequencing, respectively. A final genome assembly, with a scaffold N50 size of 4.65 Mb and a total length of 1.51 Gb, was obtained by primary assembly based on PacBio long reads plus scaffolding with 10× Genomics reads. Identified repeats constituted ∼82% of the genome, and 24,064 protein-coding genes were predicted with high support. The genome has low heterozygosity and shows no evidence for recent whole genome duplication. Metabolic pathway genes relating to the accumulation of long-chain fatty acid were identified and studied in detail., Conclusions: Here, we provide the first genome assembly and gene annotation for M. oleifera. The availability of these resources will be of great importance for conservation biology and for the functional genomics of nervonic acid biosynthesis., (© The Author(s) 2019. Published by Oxford University Press.)

Aim: To prepare TK-gene nanoparticles and investigate its expression., Methods: Biodegradable and biocompatible polymer polylactic-co-glycolic acid (PLGA) was used to prepare recombinant plasmid pEGFP-AFP nanoparticles by double-emulsion evaporation technique. The characteristics of the nanopticicles including morphology, entrapment efficiency was investigated. The expression of TK gene was also investigated by MTT assay, which could determine the dying cells after the addition of gancyclovir (GCV). The enhanced green fluorescent protein (EGFP) expression in human hepatocarcinoma SMMC-7221 cells and human normal parenchymal Chang liver cells were assessed by flow cytometric analysis., Results: The resulting plasmid-nanoparticles had regular spherical surface and a narrow particle size with a mean diameter of (72 +/- 12) nm, The average entrapment efficiency was 91.25%, the enhanced transfection efficiency and ability protecting plasmid DNA from degraded by nuclease or sonication due to nanoparticles encapsulation., Conclusion: DNA-nanoparticles need further study as gene delivery system.