[Responses of jasmonates and tanshinones in Danshen to mechanical wounding induction].

When plants are subjected to mechanical wounding(MW)caused by insect feeding, extreme weather, and human factors, they rapidly initiate a series of response mechanisms at the transcriptional and metabolic levels, leading to changes in the content of phytohormone and secondary metabolites in plants. In this study, using the medicinal model plant Danshen(Salvia miltiorrhiza) as an example, the effect of MW on the metabolism of medicinal plants was evaluated. By virtue of qRT-PCR and LC-MS, the changes in the biosynthetic genes and contents of jasmonates(JAs) and tanshinones in response to leaf damage stimulation were detected to reveal the related patterns of transcription and metabolism in leaves and roots at different time points after MW treatment, thus exploring the response mechanism of Danshen to MW stress. The results showed that MW induction could transiently increase the expression of biosynthetic genes of Jas, with AOC and JAR beginning to increase and peaking at 2 h after induction, while AOS and OPR3 peaked at 4 h. Correspondingly, the content of OPDA, JA, and JA-Ile all peaked at 2 h. In the biosynthesis of tanshinones, the diterpene synthase genes CPS1 and KSL1 both peaked at 2 h, while the subsequent modification genes CYP450s all peaked at 4 h. The content of the four tanshinones showed a continuous increase trend within 8 h. This study provides a reference for revealing the research on secondary metabolite accumulation under MW stress and lays a foundation for further understanding the role of Jas in enhancing plant resistance, promoting the accumulation of active ingredients, and improving the quality of medicinal materials under MW stress.

Functional characterization of sesquiterpene synthase in Mongolian medicine Syringa oblata in heartwood formation.

Lilac (Syringa oblata) is a well-known horticultural plant, and its aromatic heartwood is widely utilized in Traditional Mongolian Medicine for treating angina. However, limited research on the dynamic changes and mechanisms of aromatic substance formation during heartwood development hinders the analysis and utilization of its medicinal components. In this study, volatile metabolome analysis revealed that sesquiterpenes are the primary metabolites responsible for the aroma in heartwood, with cadinane and eremophilane types being the most prevalent. Among the identified sesquiterpene synthases, SoSTPS1-5 exhibited significantly increased expression in heartwood formation and was selected for further investigation. Molecular docking simulations predicted multiple amino acid binding sites and confirmed its ability to catalyze the formation of eremophilane, copaene, cadinane, germacrane, and elemane-type sesquiterpenes from FPP (farnesyl pyrophosphate). Co-expression and promoter analysis suggested a transcriptional regulatory network primarily involving WRKY transcription factors. Additionally, aiotic and biotic stress inducers, such as Ag+, Fusarium oxysporum, and especially MeJA, were found to activate the expression of SoSTPS1-5 and promote sesquiterpene accumulation. This study provides insights into the basis of medicinal substance formation and the potential mechanisms of sesquiterpene accumulation in lilac heartwood, laying a foundation for future research on the biosynthesis and utilization of its medicinal components.

[A new sesquiterpene from Syringa oblata].

In this study, the chemical components of ethanol extract from the aromatic parts of Syringa oblata were systematically separated and purified by silica gel column chromatography, thin layer plate preparation and liquid phase preparation. Combined with ultraviolet analyzer(UV), infrared analyzer(IR), nuclear magnetic resonance analyzer(NMR), high resolution mass spectrometer(HR-ESI-MS), X-ray diffraction and other spectrum technology as well as literature physicochemical data comparison methods for structural identification, a total of 10 compounds were identified. They were identified as oblatanoid D(1),(-)-T-muurolol(2), oblatanoid E-G(3-5), 14-noreudesma-3-hydroxy-3-en-2,9-dione(6), 1-isopropyl-2,7-dimethylnaphthalene(7), isocoradiol(8), α-calacorene(9), cadin-4-en-1-ß-ol(10). Compound 1 is a new sesquiterpene compound that has not been reported, and the other 9 compounds are isolated from S. oblata for the first time. The compound 1 has a significant protective effect on the LPS-induced inflammatory injury model of RAW264.7 cells.

Unveiling the regulatory mechanisms of nodules development and quality formation in Panax notoginseng using multi-omics and MALDI-MSI.

INTRODUCTION: Renowned for its role in traditional Chinese medicine, Panax notoginseng exhibits healing properties including bidirectional regulatory effects on hematological system diseases. However, the presence of nodular structures near the top of the main root, known as nail heads, may impact the quality of the plant's valuable roots. OBJECTIVES: In this paper, we aim to systematically analyze nail heads to identify their potential correlation with P. notoginseng quality. Additionally, we will investigate the molecular mechanisms behind nail head development. METHODS: Morphological characteristics and anatomical features were analyzed to determine the biological properties of nail heads. Active component analysis and MALDI mass spectrometry imaging (MALDI-MSI) were performed to determine the correlation between nail heads and P. notoginseng quality. Phytohormone quantitation, MALDI-MSI, RNA-seq, and Arabidopsis transformation were conducted to elucidate the mechanisms of nail head formation. Finally, protein-nucleic acid and protein-protein interactions were investigated to construct a transcriptional regulatory network of nodule development and quality formation. RESULTS: Our analyses have revealed that nail heads originate from an undeveloped lateral root. The content of ginsenosides was found to be positively associated with the amount of nail heads. Ginsenoside Rb1 specifically accumulated in the cortex of nail heads, while IAA, tZR and JAs also showed highest accumulation in the nodule. RNA-seq analysis identified PnIAA14 and PnCYP735A1 as inhibitors of lateral root development. PnMYB31 and PnMYB78 were found to form binary complexes with PnbHLH31 to synergistically regulate the expression of PnIAA14, PnCYP735A1, PnSS, and PnFPS. CONCLUSION: Our study details the major biological properties of nodular structures in P. notoginseng and outlines their impact on the quality of the herb. It was also determined that PnMYB31- and PnMYB78-PnbHLH31 regulate phytohormones and ginsenosides accumulation, further affecting plant development and quality. This research provides insights for quality evaluation and clinical applications of P. notoginseng.

Transcriptional regulatory network of high-value active ingredients in medicinal plants.

High-value active ingredients in medicinal plants have attracted research attention because of their benefits for human health, such as the antimalarial artemisinin, anticardiovascular disease tanshinones, and anticancer Taxol and vinblastine. Here, we review how hormones and environmental factors promote the accumulation of active ingredients, thereby providing a strategy to produce high-value drugs at a low cost. Focusing on major hormone signaling events and environmental factors, we review the transcriptional regulatory network mediating biosynthesis of representative active ingredients. In this network, many transcription factors (TFs) simultaneously control multiple synthase genes; thus, understanding the molecular mechanisms affecting transcriptional regulation of active ingredients will be crucial to developing new breeding possibilities.

Phytochemical and pharmacological progress on Syringa oblata, a traditional Mongolian medicine.

Syringa oblata is a traditional Mongolian medicine mainly distributed in the Helan Mountains (the boundaries of Inner Mongolia and Ningxia, China) and the north of Yan Mountains (Aohan Qi, Inner Mongolia, China). It is clinically used to treat diseases caused by Heyi, such as heartache and heat pathogen in the heart. Phytochemical studies on S. oblata revealed the presence of iridoids, lignans, triterpenes, phenylpropanoids, phenylethanoids, and volatile components. Pharmacological investigations revealed a broad spectrum of bioactivities, such as antimicrobial, antioxidant, antiproliferative, and hepatoprotective effects. This article summarized the chemical components and pharmacological activities of S. oblata, providing a scientific rationale for its bioactive constituents, quality control, and utilization as an important medicine.

Comparative Transcriptomics and Metabolites Analysis of Two Closely Related Euphorbia Species Reveal Environmental Adaptation Mechanism and Active Ingredients Difference.

Roots of Euphorbia fischeriana and Euphorbia ebracteolata are recorded as the source plant of traditional Chinese medicine "Langdu," containing active ingredients with anticancer and anti-AIDS activity. However, the two species have specific patterns in the graphic distribution. Compared with E. ehracteolata, E. fischeriana distributes in higher latitude and lower temperature areas and might have experienced cold stress adaptation. To reveal the molecular mechanism of environmental adaptation, RNA-seq was performed toward the roots, stems, and leaves of E. fischeriana and E. ehracteolata. A total of 6,830 pairs of putative orthologs between the two species were identified. Estimations of non-synonymous or synonymous substitution rate ratios for these orthologs indicated that 533 of the pairs may be under positive selection (Ka/Ks > 0.5). Functional enrichment analysis revealed that significant proportions of the orthologs were in the TCA cycle, fructose and mannose metabolism, starch and sucrose metabolism, fatty acid biosynthesis, and terpenoid biosynthesis providing insights into how the two closely related Euphorbia species adapted differentially to extreme environments. Consistent with the transcriptome, a higher content of soluble sugars and proline was obtained in E. fischeriana, reflecting the adaptation of plants to different environments. Additionally, 5 primary or secondary metabolites were screened as the biomarkers to distinguish the two species. Determination of 4 diterpenoids was established and performed, showing jolkinolide B as a representative component in E. fischeriana, whereas ingenol endemic to E. ebracteolate. To better study population genetics, EST-SSR markers were generated and tested in 9 species of Euphorbia. A total of 33 of the 68 pairs were screened out for producing clear fragments in at least four species, which will furthermore facilitate the studies on the genetic improvement and phylogenetics of this rapidly adapting taxon. In this study, transcriptome and metabolome analyses revealed the evolution of genes related to cold stress tolerance, biosynthesis of TCA cycle, soluble sugars, fatty acids, and amino acids, consistent with the molecular strategy that genotypes adapting to environment. The key active ingredients of the two species were quantitatively analyzed to reveal the difference in pharmacodynamic substance basis and molecular mechanism, providing insights into rational crude drug use.

Increasing Expression of PnGAP and PnEXPA4 Provides Insights Into the Enlargement of Panax notoginseng Root Size From Qing Dynasty to Cultivation Era.

Root size is a key trait in plant cultivation and can be influenced by the cultivation environment. However, physical evidence of root size change in a secular context is scarce due to the difficulty in preserving ancient root samples, and how they were modified during the domestication and cultivation stays unclear. About 100 ancient root samples of Panax notoginseng, preserved as tribute in the Palace Museum (A.D. 1636 to 1912, Qing dynasty), provided an opportunity to investigate the root size changes during the last 100 years of cultivation. The dry weight of ancient root samples (~120 tou samples, tou represents number of roots per 500 g dry weight) is 0.22-fold of the modern samples with the biggest size (20 tou samples). Transcriptome analysis revealed that PnGAP and PnEXPA4 were highly expressed in 20 tou samples, compared with the 120 tou samples, which might contribute to the thicker cell wall and a higher content of lignin, cellulose, and callose in 20 tou samples. A relatively lower content of dencichine and higher content of ginsenoside Rb1 in 20 tou samples are also consistent with higher expression of ginsenoside biosynthesis-related genes. PnPHL8 was filtrated through transcriptome analysis, which could specifically bind the promoters of PnGAP, PnCYP716A47, and PnGGPPS3, respectively. The results in this study represent the first physical evidence of root size changes in P. notoginseng in the last 100 years of cultivation and contribute to a comprehensive understanding of how the cultivation environment affected root size, chemical composition, and clinical application.

Eremophilane and Cadinene Sesquiterpenes from Syringa oblata and Their Protective Effects against Hypoxia-Induced Injury on H9c2 Cells.

Seven sesquiterpenes including four eremophilanes (1-4) and three cadinenes (5-7), were isolated from the heartwood of Syringa oblata Lindl. Among them, three new eremophilane-type sesquiterpenes were identified and named oblatanoids A-C (1-3), respectively. Their structures were established by extensive analyses of spectroscopic methods, and their absolute configurations were determined by electronic circular dichroism (ECD) calculations. All these new compounds were evaluated for protective effects against hypoxia-induced injury on H9c2 cells, and 1-3 exhibited significantly protective activities toward H9c2 cells in vitro.

The ERF-VII transcription factor SmERF73 coordinately regulates tanshinone biosynthesis in response to stress elicitors in Salvia miltiorrhiza.

Here, we investigate the role of SmERF73, a group VII ETHYLENE RESPONSE FACTOR stress response transcription factor, in the regulation of post-modification of the skeleton precursors of diterpene tanshinones in Salvia miltiorrhiza. Most genes found to be involved in tanshinone biosynthesis are located on chromosome 6, and five of these genes comprise a large gene cluster in S. miltiorrhiza. We found that SmERF73 overexpression in S. miltiorrhiza coordinately up-regulated the transcription of seven tanshinone biosynthetic genes, four of which were located in the tanshinone gene cluster, consequently increasing tanshinone accumulation, while SmERF73 silencing reduced corresponding gene transcription and tanshinone accumulation. SmERF73 recognizes GCC-box promoter elements of four tanshinone-associated genes (DXR1, CPS1, KSL1 and CYP76AH3) and activates their expression. Moreover, SmERF73 and its targets were up-regulated by stress elicitors; SmERF73 appears to be at least partly mediated by the jasmonic acid (JA) signaling pathway via interaction with SmJAZ3. SmERF73 coordinately regulates tanshinone biosynthetic gene expression, suggesting a potential link between tanshinone production and plant stress responses.

[Cloning and expression analysis of 5-phosphomevalonate kinase gene (CcPMK) in Cinnamomum camphora].

The 5-phosphomevalonate kinase(PMK) is a key enzyme in mevalonate(MVA) pathway which reversibly catalyzes the phosphorylation of mevalonate 5-phosphate(MVAP) to form mevalonate-5-diphosphate(MVAPP) in the presence of ATP and divalent metal ion such as Mg~(2+). In this research, on the basis of the transciptome database of Cinnamomum camphora, the PMK was cloned by cDNA from C. camphora, and was named CcPMK(GenBank number KU886266). The ORF of CcPMK was composed of 1 545 bp, encoding 514 amino acids. The bioinformatics analysis of CcPMK indicated that the molecular weight of the encoded protein was 56.14 kDa, with a theoretically isoelectric point of 7.64, and there was no signal peptide and transmembrane structure in putative protein. By multiple sequence alignment and phylogenetic tree analysis, we found that similarity between CcPMK and PMK amino acid sequence of other plants was as high as 75%. Among the similar sequences, 45% of them belonged to the alpha helix, while 16% belonged to the beta strand. CcPMK obtained 3 PMK protein family motifs and 1 ATP binding site Gly-Leu-Gly-Ser-Ser-Ala-Ala, and its 3 D structure contained a catalytic pocket structure, proving CcPMK as a member of PMK gene family. The result of phylogenetic tree showed that CcPMK was closely related to monocotyledon plants such as Phonenix dactylifera. The results of the Real-time PCR indicated that the expression level of CcPMK in borneol type was higher than that in linalool type, cineol type, iso-nerolidol type and camphor type. CcPMK expressed highest in roots and lowest in branches. Our results revealed that the expression level of CcPMK was different among five chemical types and different plant tissues, and the research provides foundation for further study of the terpenoids biosynthetic pathway in C. camphora.

A Novel Interference Suppression Method for Interrupted Sampling Repeater Jamming Based on Singular Spectrum Entropy Function.

As a new type of jamming, the interrupted sampling repeater jamming (ISRJ) derived from the digital radio frequency memory (DRFM) technology, can generate coherent multiple false targets after pulse compression. At present, the traditional interference suppression method and its improved methods have insufficient characteristics and poor detection performance under the condition of low signal-to-noise ratio (SNR). Aiming at addressing this defect, this paper proposes an interference suppression method for ISRJ based on singular spectrum entropy function (SSEF) from the aspects of singular value decomposition (SVD) and information entropy theories. In this method, firstly, considering the local fine characteristics and extraction efficiency, an adaptive multi-scale segmentation (AMS) method is proposed. The purpose of this processing is to extend the salient characteristics while to smooth the similar ones. In AMS, the segmentation criterion based on average energy of segments and the constraint of minimum segmentation is also proposed, then the improved delay embedded matrix is established from the improved trajectory matrix by AMS and delay embedded mapping. Secondly, the singular spectrum of the improved delay embedded matrix is extracted by SVD. Thirdly, because the recognition algorithms based on singular spectrum analysis (SSA), classical SSE and other characteristics fail at low SNR, this paper proposes a characteristic named as SSEF retrieved from the Shannon entropy model. The following proposed entropy-based threshold detection is carried out on the echo signal to realize the band-pass filtering and interference suppression. Finally, experiment results show that in comparison with other interference suppression approaches, SSEF can increase the probability of target detection and the peak-to-side-lobe ratio (PSR) after pulse compression, which validates its stability to noise and jamming especially in the condition of low SNRs.