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Licorice, one of the most commonly used medicinal materials in China, grows mainly in arid and semi-arid regions and has important economic and ecological values. Basic leucine zipper (bZIP) transcription factors in plants play an important role in regulating biological or abiotic stress responses, growth, and secondary metabolite synthesis. bZIP transcription factors in the published whole genome database of Glycyrrhiza uralensis were identified using bZIP sequences found in Arabidopsis thaliana genome as reference, and ABA-dependent bZIP genes were identified by using Illumina high-throughput sequencing. The physical and chemical properties, structure of the encoded proteins, and the gene expression patterns with exogenous ABA stress were analyzed. A total of 69 bZIP transcription factor genes were identified in G. uralensis, named Gubzip1-69, and they were divided into 10 subfamilies (A-I and S) according to their similarity to bZIPs of A. thaliana. By calculating the relative expression levels of the 69 GubZIPs genes under different concentrations of exogenous ABA stress, genes that may be involved in the regulation of ABA signaling pathways were identified, namely GubZIP1, GubZIP5, GubZIP8, GubZIP30, GubZIP33 and GubZIP56. The results of expression pattern analysis of these GubZIPs genes under exogenous ABA stress showed that the expression pattern of GubZIPs genes changed significantly with 50 mg·L-1 ABA. The relative expression levels of these genes decreased 3 h after treatment, and gradually increased 6 h after treatment. Except for GubZIP8, the relative expression levels of these genes were significantly increased after 12 h. Further research on the function of bZIP transcription factors of G. uralensis and elucidating their regulatory mechanisms should be of interest and will provide a scientific basis for cultivating high-quality cultivars of G. uralensis through molecular breeding methods.
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italic>Dendrobium moniliforme is an important source of Dendrobii Caulis and one of the main sources of authentic Fengdou. The complete chloroplast genome of D. moniliforme was sequenced using Illumina Hiseq technology and its gene map and genomic structure were analyzed. Then comparative and phylogenetic analysis of the complete chloroplast genomes of D. moniliforme and its related species were conducted. The chloroplast genome of D. moniliforme was 150 754 bp in length and had a typical quadripartite structure with a large single copy (LSC, 84 818 bp), a small single copy (SSC, 14 124 bp) and two inverted repeats (IRs, 25 906 bp each). A total of 123 chloroplast genes were annotated, including 77 protein-coding genes, 38 tRNA genes and 8 rRNA genes, of which 17 genes contained introns. Bioinformatics analysis identified 53 SSR sites, most of which had A-T base preference. A phylogenetic tree was constructed using the chloroplast genome sequences of 33 Dendrobium species. The results showed that Dendrobium complex species were clustered in a single large branch, indicating that they were closely related. This study provides a scientific basis for the identification of D. moniliforme and the phylogenetic relationship of D. moniliforme complex species necessary for Herbgenomics research.
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Unraveling the genetic basis of medicinal plant metabolism and developmental traits is a long-standing goal for pharmacologists and plant biologists. This paper discusses the definition of molecular genetics of medicinal plants, which is an integrative discipline with medicinal plants as the research object. This discipline focuses on the heredity and variation of medicinal plants, and elucidates the relationship between the key traits of medicinal plants(active compounds, yield, resistance, etc.) and genotype, studies the structure and function, heredity and variation of medicinal plant genes mainly at molecular level, so as to reveal the molecular mechanisms of transmission, expression and regulation of genetic information of medicinal plants. Specifically, we emphasize on three major aspects of this discipline.(1)Individual and population genetics of medicinal plants, this part mainly highlights the genetic mechanism of the domestication, the individual genomics at the species level, and the formation of genetic diversity of medicinal plants.(2)Elucidation of biosynthetic pathways of active compounds and their evolutionary significance. This part summarizes the biosynthesis, diversity and molecular evolution of active compounds in medicinal plants.(3) Molecular mechanisms that shaping the key agronomic traits by internal and external factors. This part focuses on the accumulation and distribution of active compounds within plants and the regulation of metabolic network by environmental factors. Finally, we prospect the future direction of molecular genetics of medicinal plants based on the rapid development of multi-omics technology, as well as the application of molecular genetics in the future strategies to achieve conservation and breeding of medicinal plants and efficient biosynthesis of active compounds.
Sujet(s)
Voies de biosynthèse , Génomique , Biologie moléculaire , Amélioration des plantes , Plantes médicinalesRÉSUMÉ
As abscisic acid (ABA) receptor, the pyrabactin resistance 1-like (PYR/PYL) protein (named PYL for simplicity) plays an important part to unveil the signal transduction of ABA and its regulatory mechanisms. Glycyrrhiza uralensis, a drought-tolerant medicinal plant, is a good model for the mechanism analysis of ABA response and active compound biosynthesis. However, knowledge about PYL family in G. uralensis remains largely unknown. Here, 10 PYLs were identified in G. uralensis genome. Characterization analysis indicated that PYLs in G. uralensis (GuPYLs) are relatively conserved. Phylogenetic analysis showed that GuPYL1-3 belongs to subfamily I, GuPYL4-6 and GuPYL10 belong to subfamily II and GuPYL7-9 belongs to subfamily III. In addition, transcriptome data presented various expression levels of GuPYLs under different exogenous ABA stresses. The expression pattern of GuPYLs was verified by Quantitative real-time polymerase chain reaction (qRT-PCR). The study proved that GuPYL4, GuPYL5, GuPYL8 and GuPYL9 genes are significantly up-regulated by ABA stress and the response process is dynamic. This study paves the way for elucidating the regulation mechanism of ABA signal to secondary metabolites and improving the cultivation and quality of G. uralensis using agricultural strategies.
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Camptotheca acuminata produces camptothecin (CPT), a monoterpene indole alkaloid (MIA) that is widely used in the treatment of lung, colorectal, cervical, and ovarian cancers. Its biosynthesis pathway has attracted significant attention, but the regulation of CPT biosynthesis by the APETALA2/ethylene-responsive factor (AP2/ERF) transcription factors (TFs) remains unclear. In this study, a systematic analysis of the AP2/ERF TFs family in C. acuminata was performed, including phylogeny, gene structure, conserved motifs, and gene expression profiles in different tissues and organs (immature bark, cotyledons, young flower, immature fruit, mature fruit, mature leaf, roots, upper stem, and lower stem) of C. acuminata. A total of 198 AP2/ERF genes were identified and divided into five relatively conserved subfamilies, including AP2 (26 genes), DREB (61 genes), ERF (92 genes), RAV (18 genes), and Soloist (one gene). The combination of gene expression patterns in different C. acuminata tissues and organs, the phylogenetic tree, the co-expression analysis with biosynthetic genes, and the analysis of promoter sequences of key enzymes genes involved in CPT biosynthesis pathways revealed that eight AP2/ERF TFs in C. acuminata might be involved in CPT synthesis regulation, which exhibit relatively high expression levels in the upper stem or immature bark. Among these, four genes (CacAP2/ERF123, CacAP2/ERF125, CacAP2/ERF126, and CacAP2/ERF127) belong to the ERF-B2 subgroup; two genes (CacAP2/ERF149 and CacAP2/ERF152) belong to the ERF-B3 subgroup; and two more genes (CacAP2/ERF095 and CacAP2/ERF096) belong to the DREB-A6 subgroup. These results provide a foundation for future functional characterization of the AP2/ERF genes to enhance the biosynthesis of CPT compounds of C. acuminata.
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Objective To study virulence factors and drug resistance mechanism of linezolid-intermediate Enterococcus faecalis(E.faecalis) isolated from patients with bloodstream infection.Methods Two linezolid-intermediate E.faecalis strains,namely A and B,were isolated from two patients with bloodstream infection,the treatment of two patients was analyzed.The minimum inhibitory concentration (MIC) of linezolid and vancomycin were determined.The virulence genes (esp,asa1,gelE,ace,agg,efaA,cylA,and hyl) and linezolid resistance genes (domain V region of the 23SrRNA,cfr,cfr[B],optrA) were amplified by polymerase chain reaction (PCR).PCR products of domain V region of 23SrRNA gene were sequenced and analyzed.Results Symptoms of two patients who isolated two linezolid-intermediate E.faecalis strains were controlled after accepted linezolid therapy.Strains A and B were both susceptible to vancomycin(MICs were 1μg/mL and 4μg/mL respectively),teicoplain,ampicillin,and nitrofurantoin,while intermediate to linezolid(MIC were both 4μg/mL).Two strains both contained multiple virulence factors,strain A were negative for cylA and hyl,strain B were negative for hyl and esp,but positive for other virulence genes.There was G2621T mutation in domain V region of 23SrRNA in strain A,and no variation was found in strain B.Drug resistance genes of cfr,cfr(B),and optrA were all negative in both strain A and B.Conclusion In the present study,two linezolid-intermediate E.faecalis strains isolated from patients with bloodstream infection were susceptible to vancomycin and ampicillin,although the treatment of linezolid in two patients is effective,the utilization of linezolid therapy in clinical practice still needs to be cautious.The mutation of target site is a significant resistance mechanism,it is necessary for us to pay more attention to these clinical strains which are non-susceptible to such antimicrobial agents,and the treatment strategy needs further study.
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Natural products from plant secondary metabolits are a major source of clinical drugs and industrial chemicals. Salvia miltiorrhiza is one of the most important plants in traditional Chinese medicine. Its dried roots and rhizomes are highly valued for use in the treatment of vascular diseases and for their anti-oxidative activities. Furthermore, S. miltiorrhiza is described as a medicinal model plant mainly due to its biosynthesis of active compounds. Here, we reviewed the research on S. miltiorrhiza in genomics, transcriptomics, biosynthesis of tanshinones and phenolic acids, biotic and abiotic elicitors, and regulation of transcription factors. This will provide a solid foundation for new breeding and synthetic biology approaches to produce and study natural products.
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In order to authenticate the components of antler powder in the market, DNA barcoding technology coupled with cloning method were used. Cytochrome c oxidase subunit I (COI) sequences were obtained according to the DNA barcoding standard operation procedure (SOP). For antler powder with possible mixed components, the cloning method was used to get each COI sequence. 65 COI sequences were successfully obtained from commercial antler powders via sequencing PCR products. The results indicates that only 38% of these samples were derived from Cervus nippon Temminck or Cervus elaphus Linnaeus which is recorded in the 2010 edition of "Chinese Pharmacopoeia", while 62% of them were derived from other species. Rangifer tarandus Linnaeus was the most frequent species among the adulterants. Further analysis showed that some samples collected from different regions, companies and prices, contained adulterants. Analysis of 36 COI sequences obtained by the cloning method showed that C. elaphus and C. nippon were main components. In addition, some samples were marked clearly as antler powder on the label, however, C. elaphus or R. tarandus were their main components. In summary, DNA barcoding can accurately and efficiently distinguish the exact content in the commercial antler powder, which provides a new technique to ensure clinical safety and improve quality control of Chinese traditional medicine
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Animaux , Andouillers , Codage à barres de l'ADN pour la taxonomie , Cervidae , Médecine traditionnelle chinoise , Réaction de polymérisation en chaîne , Poudres , Contrôle de qualitéRÉSUMÉ
The medicinal fungi, which are of great importance in traditional medicine, are facing the problems of wild resources scarcity and low concentration of bioactive compounds. Velvet family and LaeA global regulator play a vital role in secondary metabolism and developmental programs, which are found in a wide variety of fungi ranging from Chytridiomycota to Basidiomycota. This review elaborates the structures and functions between Velvet family and LaeA protein. The Velvet family which shares the Velvet protein domain, including VeA (Velvet), VelB (Velvet like B), VosA (viability of spores A) and VelC (Velvet like C), acts on the regulation function is secondary metabolism and developmental programs such as asexual and sexual development. Furthermore, the function is affected by environmental factors such as light and temperature. LaeA protein which owns S-adenosylmethionine-dependent methyltransferase domain, coordinately regulates development and secondary metabolism by regulating and modifying the Velvet proteins. The regulation of LaeA is mediated by light receptor proteins. Therefore, clarifying the mechanism of Velvet and LaeA proteins in medicinal fungi will pave the way for nurturing medicinal fungi and improving production of bioactive compounds.
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Protéines fongiques , Métabolisme , Champignons , Chimie , Régulation de l'expression des gènes fongiques , Gènes régulateurs , Structure tertiaire des protéines , Métabolisme secondaire , Relation structure-activitéRÉSUMÉ
Transcription factor is one of the key factors in the regulation of gene expression at the transcriptional level. It plays an important role in plant growth, active components biosynthesis and response to environmental change. This paper summarized the structure and classification of bHLH transcription factors and elaborated the research progress of bHLH transcription factors which regulate the active components in plants, such as flavonoids, alkaloids, and terpenoids. In addition, the possibility of increasing the concentration of active substances by bHLH in medicinal plants was assessed. The paper emphasized great significance of model plants and multidisciplinary research fields including modern genomics, transcriptomics, metabolomics and bioinformatics, providing the contribution to improve the discovery and function characterization of bHLH transcription factors. Accelerating the research in the mechanism of bHLH transcription factors on the regulation of active components biosynthesis will promote the development of breeding and variety improvement of Chinese medicinal materials, also ease the pressure of resources exhaustion of traditional Chinese medicine home and abroad.