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.
Alkaloids ; biosynthesis ; Basic Helix-Loop-Helix Transcription Factors ; chemistry ; classification ; genetics ; metabolism ; Flavonoids ; biosynthesis ; Plants, Medicinal ; genetics ; metabolism ; Terpenes ; metabolism

OBJECTIVETo investigate the effect of total flavonoids of Scutellaria baicalensis Georgi (TFSB) on exogenous expression of influenza A virus nucleoprotein (NP) in HeLa cells.

METHODSHeLa cells were transiently transfected with the empty vector pcDNA3.1(+) or pcDNA3.1(+)/NP vector harboring influenza A virus NP. The pcDNA3.1(+)/NP-transfected cells were treated with TSFB and the expression of influenza A virus NP in the cell supernatant was measured using colloidal gold immunochromatography 48 h after the transfection; fluorescent quantitative RT-PCR was performed to measure the starting copy number of NP gene.

RESULTSThe cells transfected with pcDNA3.1 (+)/NP with and without TFSB treatment were positive for NP expression. Fluorescent quantitative RT-PCR showed that the starting copy number of NP gene in pcDNA3.1(+)/NP-transfected cells was (8.90±2.53)×10⁶ copies/µl, showing no significant difference from that of (6.15±1.49)×10⁶ copies/µl in pcDNA3.1(+)/NP-transfected cells with subsequent TFSB treatment (P>0.05).

CONCLUSIONTFSB treatment does not obviously affect exogenous influenza A virus NP gene expression or its protein synthesis in HeLa cells.

Flavonoids ; pharmacology ; Gene Expression ; HeLa Cells ; Humans ; RNA-Binding Proteins ; biosynthesis ; genetics ; Scutellaria baicalensis ; Transfection ; Viral Core Proteins ; biosynthesis ; genetics

Hairy root clones of Saussurea involucrata transformed with Agrobacterium rhizogenes strains R1601, R1000, and LBA9402 were established to investigate the flavonoid production. Opine synthesis and PCR analysis confirmed the integration of the T-DNA fragment of Ri plasmid from A. rhizogenes strain R1601 into the transformed root genome. The frequency of hairy root formation from root segments, which were pre-cultured 2 days in N6 solid medium without plant growth regulators, amounted to 100% following infection with R1601 strain of A. rhizogenes. The transformed roots were kept in hormone-free N6 liquid medium in the dark at 25 degrees C, 110r/min and routinely subcultured every 20 - 24 days. One hairy root clone, which grew vigorously with lateral branches, was periodically examined for the ability to produce flavonoid. The maximum of biomass and flavonoid yield achieved 66.7 g/L (fresh weight) and 102.3mg/g dry weight after incubation 20 days. The calli were induced from the hairy root culture in the presence of 0.5mg/L IBA and intact plantlets were regenerated from these calli. The regeneration plantlets from hairy roots, in which the flavonoid content were 53% in that of untransformed plants, weren't different in growth and morphology of the untransformed plantlets. Therefore plant regeneration from hairy roots may be also a means for producing transformed S. involucrata plants. Hairy root cultures of S. involucrata clearly showed higher flavonoid contents compared to the wild plant or the regeneration seedlings. As the wild S. involucrata grows only in special regions with peculiar climate, and cultivation of this species in a normal climate has been unsuccessful so far. The success in obtaining a method for high production of flavonoid might very well be one of the solutions for this problem in the future.
Culture Techniques ; Flavonoids ; biosynthesis ; Plant Roots ; growth & development ; Rhizobium ; physiology ; Saussurea ; growth & development

Flavonoids are a group of secondary metabolites found in plants. They have many pharmacological functions and play an important role in Chinese sumac( Rhus chinensis),which is a well-known traditional Chinese medicinal plant. Chalcone isomerase( CHI,EC 5. 5. 1. 6) is one of the key enzymes in the flavonoids biosynthesis pathway. In this paper,the full-length c DNA sequence encoding the chalcone isomerase from R. chinensis( designated as Rc CHI) was cloned by RT-PCR and rapid-amplification of c DNA Ends( RACE). The Rc CHI c DNA sequence was 1 058 bp and the open reading frame( ORF) was 738 bp. The ORF predicted to encode a 245-amino acid polypeptide. Rc CHI gene contained an intron and two exons. The sequence alignments revealed Rc CHI shared47. 1%-71. 6% identity with the homologues in other plants. Real-time PCR analysis showed that the total flavonoid levels were positively correlated with tissue-specific expressions of Rc CHI mRNA in different tissues. The recombinant protein was successfully expressed in an Escherichia coli strain with the p GEX-6 P-1 vector. In this paper,the CHI gene was cloned and characterized in the family of Anacardiaceae and will help us to obtain better knowledge of the flavonoids biosynthesis of the flavonoid compounds in R. chinensis.
Cloning, Molecular ; DNA, Complementary ; Flavonoids ; biosynthesis ; Intramolecular Lyases ; genetics ; Plants, Medicinal ; enzymology ; genetics ; Rhus ; enzymology ; genetics

Ziziphora bungeana is a kind of medicinal plants belongs to Labiatae,and it also a kind of geoherbs in Xinjiang. The main active ingredient linarin has a higher content in inflorescence than in other parts. In this study,high-throughput sequencing technology was used to reveal the transcriptome of the inflorescence of Z. bungeana,77 366 unigenes were acquired,of which 56 375 unigenes were annotated based on search of the database and classification. Through the analysis of metabolic pathways,sixty unigenes were probably encoding some enzymes involved in the flavonoid biosynthesis pathways. The contents of linarin in different parts were determined and the key genes were verified by qRT-PCR. The discovery provides the research basis for further analysis of the enzyme genes involved in the biosynthesis of the major flavonoid components in Z. bungeana.
Flavonoids ; biosynthesis ; Gene Expression Profiling ; High-Throughput Nucleotide Sequencing ; Lamiaceae ; chemistry ; Transcriptome

Scutellaria baicalensis (S. baicalensis) and Scutellaria barbata (S. barbata) are common medicinal plants of the Lamiaceae family. Both produce specific flavonoid compounds, including baicalein, scutellarein, norwogonin, and wogonin, as well as their glycosides, which exhibit antioxidant and antitumor activities. Here, we report chromosome-level genome assemblies of S. baicalensis and S. barbata with quantitative chromosomal variation (2n = 18 and 2n = 26, respectively). The divergence of S. baicalensis and S. barbata occurred far earlier than previously reported, and a whole-genome duplication (WGD) event was identified. The insertion of long terminal repeat elements after speciation might be responsible for the observed chromosomal expansion and rearrangement. Comparative genome analysis of the congeneric species revealed the species-specific evolution of chrysin and apigenin biosynthetic genes, such as the S. baicalensis-specific tandem duplication of genes encoding phenylalanine ammonia lyase and chalcone synthase, and the S. barbata-specific duplication of genes encoding 4-CoA ligase. In addition, the paralogous duplication, colinearity, and expression diversity of CYP82D subfamily members revealed the functional divergence of genes encoding flavone hydroxylase between S. baicalensis and S. barbata. Analyzing these Scutellaria genomes reveals the common and species-specific evolution of flavone biosynthetic genes. Thus, these findings would facilitate the development of molecular breeding and studies of biosynthesis and regulation of bioactive compounds.
Evolution, Molecular ; Flavonoids/biosynthesis* ; Genome, Plant ; Plant Extracts/genetics* ; Scutellaria/metabolism* ; Whole Genome Sequencing

The effects of different physical and chemical factors on hairy root growth and flavonoids production were studied in suspension culture of Saussurea medusa hairy root in 1/2 MS medium. The results showed that the following culture conditions, nitrogen concentratiaon (involved NH4+ and NO3-), 30 mmol/L; the ratio of ammonium to nitrate, 5:25; the combination of 2% sucrose and 3% glucose; 0.5 mg/L GA3; 0.5 mg/L IBA; initial pH 5.8; light cycle, 18 h/d (3500lx); temperature, 24 degrees C; shaker revolutions per minute, 100 r/min, were favourable to hairy root growth and flavonoids production. Under the above culture conditions, up to 12.8 g/L (DW) of hairy root and 1922 mg/L of flavonoids were obtained after 21 days of culture. The content of total flavonoids in hairy root was 15%, which was about 25 times as that in the wild plantlet.
Culture Media ; Flavonoids ; biosynthesis ; Plant Roots ; growth & development ; metabolism ; Saussurea ; growth & development ; metabolism ; Temperature ; Tissue Culture Techniques

OBJECTIVETo determine the effects of Chinese herbal monomers such as baicalin, berberine, and matrine on the androgen receptor (AR) mRNA expression in SZ95 sebocytes in vitro and to explore the possible mechanism of using traditional Chinese medicines to treat acne.

METHODSSZ95 sebocytes were cultured and then treated with berberine, baicalin, matrine, and 13-cis-retinoic acid for 24 hours. Reverse transcription polymerase chain reaction was applied to detect the changes of AR.

RESULTAR mRNA was downregulated by 13-cis-retinoic acid of 1 x 10(-5) mol/L and 1 x 10(-6) mol/L, and by baicalin of 1 x 10(-4) mol/L (P < 0.05).

CONCLUSION13-cis-retinoic acid and baicalin may exert antiandrogenitic action by inhibiting AR mRNA expression in human sebocytes.

Androgen Antagonists ; pharmacology ; Cell Line ; Down-Regulation ; Drugs, Chinese Herbal ; pharmacology ; Flavonoids ; pharmacology ; Humans ; RNA, Messenger ; biosynthesis ; Receptors, Androgen ; biosynthesis ; genetics ; Skin ; cytology

OBJECTIVETo determine the effect of tea polyphenol (TP) on the proliferation of human periodontal ligament fibroblasts (HPDLFs).

METHODSHPDLFs were primary cultured from tissue explants, and the cells of the 5th to 8th passages were used after immunohistochemical identification (with SABC method) of keratin and vimentin expressions. The cells were divided into 5 groups and treated with TP at 1, 0.5, 0.25, 0.125, and 0.0625 mg/ml, respectively, with another group without TP treatment as the blank control group. Cell counting and MTT colorimetric assay were performed to assess the cell proliferation, and flow cytometry was employed to determine the DNA content of the HPDLFs.

RESULTSDifferent concentrations of TP all significantly increased the proliferation and DNA synthesis of the HPDLFs (P<0.05), and TP treatment at 0.5 mg/ml for 6 h produced the optimal effect.

CONCLUSIONTP has obviously effect in promoting the proliferation of HPDLFs.

Cell Proliferation ; drug effects ; Cells, Cultured ; DNA ; biosynthesis ; Fibroblasts ; cytology ; drug effects ; metabolism ; Flavonoids ; pharmacology ; Flow Cytometry ; Humans ; Immunohistochemistry ; Keratins ; biosynthesis ; Periodontal Ligament ; cytology ; Phenols ; pharmacology ; Polyphenols ; Tea ; chemistry ; Vimentin ; biosynthesis

OBJECTIVETo investigate the mechanism of senescence delay of human diploid fibroblast (2BS) and protecting telomere length by epimedium flavonoids (EF).

METHODSThe drug sera of EF were used to treat the 2BS. The population doublings of 2BS cells were observed, the mRNA expression of p16 gene were determined by fluorescence real-time quantitative RT-PCR, the telomerase activation of 2BS cells were determined by TRAP-Hyb, the total retinoblastoma (Rb) and phosphorated Rb protein content were detected by ELISA, the telomere length of 2BS cells were determined by telomere restriction fragment (TRF) Southern blot assay.

RESULTSEF could significantly extend the population doublings of 2BS cells, the expression of p16 mRNA was decreased and the content of phosphorated Rb protein were increased by EF. The telomere lengthening of 2BS cells were improved by EF, but the telomerase was not activated.

CONCLUSIONIn senescence human fibroblasts 2BS cells, p16 gene mRNA expression increased, content of phosphorated Rb protein decreased and the telomere length of 2BS shortened, EF might delay the aging of cells through inhibiting the p16 gene expression, promoting the production of phosphorated Rb protein and to protect the length of telomere, but not activating the telomerase.

Animals ; Cells, Cultured ; Cellular Senescence ; genetics ; Cyclin-Dependent Kinase Inhibitor p16 ; biosynthesis ; genetics ; Epimedium ; chemistry ; Fibroblasts ; cytology ; Flavonoids ; pharmacology ; Male ; RNA, Messenger ; biosynthesis ; genetics ; Rats ; Rats, Sprague-Dawley ; Retinoblastoma Protein ; metabolism ; Telomerase ; biosynthesis ; Telomere ; genetics ; metabolism ; Transduction, Genetic