This study cloned the transcription factor gene PnbHLH which held an open reading frame of 966 bp encoding 321 amino acids. This study constructed the overexpression vector of transcription factor PnbHLH of Panax notoginseng. The combination of PnbHLH overexpression and RNAi of the key enzyme gene PnCAS involved in the phytosterol biosynthesis was achieved in P. notoginseng cells, thus exploring the biosynthetic regulation of P. notoginseng saponins(PNS) by the synergistic effect of PnbHLH overexpression and PnCAS RNAi. The results showed that the PnbHLH transcription factor interacted with the promoters of key enzyme genes PnDS, PnSS and PnSE in the biosynthetic pathway of PNS, and then regulated the expression levels of key enzyme genes and affected the biosynthesis of saponins indirectly. Further study indicated that the synergistic effect of PnbHLH overexpression and PnCAS RNAi was a more effective approach to regulate the biosynthesis of saponins. Compared with the wild type and PnCAS RNAi cells of P. notoginseng, the contents of total saponins and monomeric saponins(Rd, Rb_1, Re, Rg_1 and R_1) were increased to some extent in the cell lines of PnbHLH overexpression and PnCAS RNAi. This indicated that the two ways of forward regulation and reverse regulation of saponin biosynthesis showed superposition effect. This study explored a more rational and efficient regulation strategy of PNS biosynthesis based on the advantages of multi-point regulation of transcription factors as well as the down-regulation of by-product synthesis of saponins.
Intramolecular Transferases ; Panax notoginseng ; RNA Interference ; Saponins ; Transcription Factors/genetics*

Ginsenoside Rh_2 is a rare active ingredient in precious Chinese medicinal materials such as Ginseng Radix et Rhizoma, Notoginseng Radix et Rhizoma, and Panacis Quinquefolii Radix. It has important pharmacological activities such as anti-cancer and improving human immunity. However, due to the extremely low content of ginsenoside Rh_2 in the source plants, the traditional way of obtaining it has limitations. This study intended to apply synthetic biological technology to develop a cell factory of Saccharomyces cerevisiae to produce Rh_2 by low-cost fermentation. First, we used the high protopanaxadiol(PPD)-yielding strain LPTA as the chassis strain, and inserted the Panax notoginseng enzyme gene Pn1-31, together with yeast UDP-glucose supply module genes[phosphoglucose mutase 1(PGM1), α-phosphoglucose mutase(PGM2), and uridine diphosphate glucose pyrophosphorylase(UGP1)], into the EGH1 locus of yeast chromosome. The engineered strain LPTA-RH2 produced 17.10 mg·g~(-1) ginsenoside Rh_2. This strain had low yield of Rh_2 while accumulated much precursor PPD, which severely restricted the application of this strain. In order to further improve the production of ginsenoside Rh_2, we strengthened the UDP glucose supply module and ginsenoside Rh_2 synthesis module by engineered strain LPTA-RH2-T. The shaking flask yield of ginsenoside Rh_2 was increased to 36.26 mg·g~(-1), which accounted for 3.63% of the dry weight of yeast cells. Compared with those of the original strain LPTA-RH2, the final production and the conversion efficiency of Rh_2 increased by 112.11% and 65.14%, respectively. This study provides an important basis for further obtaining the industrial-grade cell factory for the production of ginsenoside Rh_2.
Fermentation ; Ginsenosides ; Humans ; Panax/genetics* ; Panax notoginseng ; Saccharomyces cerevisiae/genetics* ; Uridine Diphosphate Glucose

According to the transcriptome dataset of Panax notoginseng, the key geranylgeranyl pyrophosphate synthase gene (GGPPS) in terpenoid backbone biosynthesis was selected to be cloned. Using specific primer pairs combining with RACE (rapid amplification of cDNA ends) technique, the full-length cDNA sequence with 1 203 bp, which containing a 1 035 bp open reading frame, was cloned and named as PnGGPPS. The corresponding full-length DNA sequence contained 2 370 bp, consisted of 1 intron and 2 exons. The deduced protein PnGGPPS contained 344 amino acids and shared more than 73% identity with GGPPS from Ricinus communis and Salvia miltiorrhiza. PnGGPPS also had specific Aspartic acid enrichment regions and other conserved domains, which belonged to the Isoprenoid-Biosyn-C1 superfamily. The quantitative real-time PCR showed that PnGGPPS expressed in different tissues of 1, 2, 3 years old root, stem, leaf and 3 years old flower, and the expression level in 3 years old leaf was significant higher than that in other organs, which suggested that it might not only be involved in the regulation of the growth and development, but also be associated with the biosynthesis of chlorophyll and carotenoids, the development of chloroplast, the shade habit and the quality formation of P. notoginseng.
Cloning, Molecular ; Computational Biology ; Geranylgeranyl-Diphosphate Geranylgeranyltransferase ; genetics ; Panax notoginseng ; genetics ; Real-Time Polymerase Chain Reaction

OBJECTIVETo comparatively determine the genetic variation and differentiation of different breeding strains of Panax notoginseng for providing the basic information for genetic breeding.

METHODThe genetic diversity and genetic structure of the 17 breeding strains of P. notoginseng were assayed by using EST-SSR molecular marker.

RESULTA total of 136 polymorphic loci of EST-SSR were detected in the 17 breeding strains of P. notoginseng, with the PIC (polymorphism information content) being 0.78, H (the gene diversity within population) being 0.139, the I (the Shannon's information index) being 0.208. Gst (coefficient of gene differentiation) was 0.382 among the 17 strains. The cluster analysis of genetic similarity showed that the 17 strains of P. notoginseng and P. stipuleanatus were classified into 4 groups, while the 17 strains of P. notoginseng were classified into three subgroups.

CONCLUSIONThe genetic differentiation was detected among the 17 strains of P. notoginseng from the same cultivation population by bulk selecting. And it was feasible to detect the effect of bulk selection by EST-SSR markers.

Breeding ; Expressed Sequence Tags ; Genetic Variation ; Microsatellite Repeats ; Panax notoginseng ; classification ; genetics ; physiology

OBJECTIVE: To evaluate toxicity of raw extract of Panax notoginseng (rPN) and decocted extract of PN (dPN) by a toxicological assay using zebrafish larvae, and explore the mechanism by RNA sequencing assay. METHODS: Zebrafish larvae was used to evaluate acute toxicity of PN in two forms: rPN and dPN. Three doses (0.5, 1.5, and 5.0 µ g/mL) of dPN were used to treat zebrafishes for evaluating the developmental toxicity. Behavior abnormalities, body weight, body length and number of vertebral roots were used as specific phenotypic endpoints. RNA sequencing (RNA-seq) assay was applied to clarify the mechanism of acute toxicity, followed by real time PCR (qPCR) for verification. High performance liquid chromatography analysis was performed to determine the chemoprofile of this herb. RESULTS: The acute toxicity result showed that rPN exerted higher acute toxicity than dPN in inducing death of larval zebrafishes (P<0.01). After daily oral intake for 21 days, dPN at doses of 0.5, 1.5 and 5.0 µ g/mL decreased the body weight, body length, and vertebral number of larval zebrafishes, indicating developmental toxicity of dPN. No other adverse outcome was observed during the experimental period. RNA-seq data revealed 38 genes differentially expressed in dPN-treated zebrafishes, of which carboxypeptidase A1 (cpa1) and opioid growth factor receptor-like 2 (ogfrl2) were identified as functional genes in regulating body development of zebrafishes. qPCR data showed that dPN significantly down-regulated the mRNA expressions of cpa1 and ogfrl2 (both P<0.01), verifying cpa1 and ogfrl2 as target genes for dPN. CONCLUSION This report uncovers the developmental toxicity of dPN, suggesting potential risk of its clinical application in children.
Animals ; Zebrafish/genetics* ; Saponins/pharmacology* ; Panax notoginseng/chemistry* ; Larva ; Sequence Analysis, RNA

The molecular markers(cpSSR, cpSNP and cpIndel) were developed based on the whole genome sequence of Panax notoginseng chloroplast genome, which provide a powerful tool for the evaluation and analysis of the future P. notoginseng germplasm resources. The 89 P. notoginseng samples from 9 groups were used for the experiment, and the data for the study were derived from NCBI and the GenBank numbers were: KJ566590, KP036468, KR021381 and KT001509. Through sequence alignment, 30 polymorphic sites(SNP and Indel) were identified, including 16 cpSNP and 14 cpIndel; cpSNP and cpIndel accounted for far more than the gene region in the intergenic region. The developed cpSSR reached 87-89, the repeat unit was mainly composed of trinucleotide, accounting for 70%-71%, and the dinucleotide was the least, accounting for 7%. Eighteen cpDNA molecular markers were developed, including 7 cpSSR primers, 6 cpIndel primers, and 5 cpSNP primers. The MatK gene and ycf1 primers were chosen as control. According to the results of DNA gel electrophoresis, cpSSR-5, pgcpir019 and pncp08 can be used to distinguish different cultivated populations of P. notoginseng. Among them, cpSSR-5 and pgcpir019 can also be used to distinguish the inter-species resources of ginseng by comprehensive sequence length, population π value and average nucleotide difference. However, pncp08 can only be used to distinguish different populations of P. notoginseng. In addition, the effect of distinguishing the groups of P. notoginseng, which the primer pncp-M(based on the MatK gene) is weaker than the cpSSR-5, pgcpir019 and pncp08.
DNA, Chloroplast/genetics* ; Genetic Markers ; Genetics, Population ; INDEL Mutation ; Panax notoginseng/genetics* ; Polymorphism, Single Nucleotide ; Sequence Alignment

With homology cloning approaches coupling with RACE (rapid-amplification of cDNA ends) techniques, the full-length coding sequence of pathogenesis-related protein PR10-1 with differential expression was cloned from the total RNA of the root of Panax notoginseng, and its function was explored furtherly. As a result, the longest 465 bp ORF (named as PnPR10-1 with the Accession No. KJ741402 in GenBank) was detected from the cloned sequence with full-length of cDNA of 863 bp. The corresponding peptide encoded consisted of 155 amino acids, contained some domains such as Bet-v-I, and showed high similarity with that from Panax ginseng by analysis of phylogenetic trees created from the alignments. Real-time quantitative PCR showed that the expression of PnPR10-1 gene was constitutive in different tissues of 1-3 year old plant, suggesting that it might be involved in growth, development, and secondary metabolism; yet it was up-regulated significantly with the infection of Fusarium oxysporum in root, suggesting that it might be involved in defense against many diseases including root rot in P. notoginseng.
Amino Acid Sequence ; Cloning, Molecular ; DNA, Complementary ; Genes, Plant ; Glycoside Hydrolases ; genetics ; Molecular Sequence Data ; Open Reading Frames ; Panax notoginseng ; genetics ; Phylogeny ; Plant Proteins ; genetics ; Plant Roots

The pharmacological mechaisms of Panax notoginseng saponins on nervous system diseases (Alzheimer's disease, Parkinson's disease, ischermic cerebral apoplexy and depressive disorder) , including panax notoginseng saponins, protoparaxotriol saponins, panasadiol saponins, ginsenoside Rg1, ginsenoside Rb1, ginsenoside Re and notoginsenoside R1 were summarized to analyze the study hotspots and potential advantages (such as estrogen-like effect) of notoginsenoside's pharmacological actions, provide reference for further pharmacological studies and new ideas for clinical treatment of nervous system diseases and drug studies and development.
Animals ; Drugs, Chinese Herbal ; administration & dosage ; Gene Expression ; drug effects ; Humans ; Nervous System Diseases ; drug therapy ; genetics ; metabolism ; Panax notoginseng ; chemistry ; Saponins ; administration & dosage

OBJECTIVETo explore the effect of Panax notoginseng saponin (PNS) on the activity and content of beta-secretase in the brain of senescence accelerated mouse-prone 8 (SAMP8) mice with Alzheimer's disease.

METHODSTotally 32 SAMP8 mice were randomly divided into the normal control group, the high dose PNS group (200 mg/kg), the low dose group (100 mg/kg), and the huperzine A group (0.3 mg/kg), 8 in each group. Equal volume of double distilled water was given to those in the normal control group. All medication was given by gastrogavage, once daily for two successive months. The activity of BACE1 was assayed by direct immunofluorescent method (DIF). The content of BACE1 protein was detected by Western blot.

RESULTSThe relative fluorescence units (RFU/microg) was 2.008 +/- 0.031 in the high dose PNS group, 2.221 +/- 0.029 in the low dose PNS group, and 2.267 +/- 0.076 in the huperzine A group, all lower than that in the normal control group (2.403 +/- 0.058; all P < 0.01). The content of BACE1 protein was 0.900 +/- 0.028 in the high dose PNS group, 1.000 +/- 0.032 in the low dose PNS group, and 0.837 +/- 0.080 in the huperzine A group, all lower than that in the normal control group (2.210 +/- 0.074, all P < 0.01).

CONCLUSIONPNS higher than 100 mg/kg could decrease the activity of BACE1 and down-regulate the content of BACE1 protein in the brain of SAMP8 mice.

Aging ; Alzheimer Disease ; metabolism ; Amyloid Precursor Protein Secretases ; metabolism ; Animals ; Aspartic Acid Endopeptidases ; metabolism ; Brain ; metabolism ; Disease Models, Animal ; Male ; Mice ; Panax notoginseng ; RNA, Messenger ; genetics ; Saponins ; pharmacology

OBJECTIVETo investigate the mechanisms of Panax notoginseng saponins (PNS) in treating coronary heart disease (CHD) by integrating gene interaction network and functional enrichment analysis.

METHODSText mining was used to get CHD and PNS associated genes. Gene-gene interaction networks of CHD and PNS were built by the GeneMANIA Cytoscape plugin. Advanced Network Merge Cytoscape plugin was used to analyze the two networks. Their functions were analyzed by gene functional enrichment analysis via DAVID Bioinformatics. Joint subnetwork of CHD network and PNS network was identifified by network analysis.

RESULTSThe 11 genes of the joint subnetwork were the direct targets of PNS in CHD network and enriched in cytokine-cytokine receptor interaction pathway. PNS could affect other 85 genes by the gene-gene interaction of joint subnetwork and these genes were enriched in other 7 pathways. The direct mechanisms of PNS in treating CHD by targeting cytokines to relieve the inflflammation and the indirect mechanisms of PNS in treating CHD by affecting other 7 pathways through the interaction of joint subnetwork of PNS and CHD network. The genes in the 7 pathways could be potential targets for the immunologic adjuvant, anticoagulant, hypolipidemic, anti-platelet and anti-hypertrophic activities of PNS.

CONCLUSIONSThe key mechanisms of PNS in treating CHD could be anticoagulant and hypolipidemic which are indicated by analyzing biological functions of hubs in the merged network.

Coronary Disease ; drug therapy ; genetics ; Gene Expression Profiling ; Gene Regulatory Networks ; drug effects ; Humans ; Panax notoginseng ; chemistry ; Phytotherapy ; Saponins ; pharmacology ; therapeutic use