Abscisic acid, a plant hormone that inhibits growth, is a key factor in balancing plant endogenous hormones and regulating growth and metabolism. Abscisic acid can improve the drought resistance and salt tolerance of crops, reduce fruit browning, reduce the incidence rate of malaria and stimulate insulin secretion, so it has a broad application potential in agriculture and medicine. Compared with traditional plant extraction and chemical synthesis, abscisic acid synthesis by microorganisms is an economic and sustainable route. At present, a lot of progress has been made in the synthesis of abscisic acid by natural microorganisms such as Botrytis cinerea and Cercospora rosea, while the research on the synthesis of abscisic acid by engineered microorganisms is rarely reported. Saccharomyces cerevisiae, Yarrowia lipolytica and Escherichia coli are common hosts for heterologous synthesis of natural products due to their advantages of clear genetic background, easy operation and friendliness for industrial production. Therefore, the heterologous synthesis of abscisic acid by microorganisms is a more promising production method. The author reviews the research on the heterologous synthesis of abscisic acid by microorganisms from five aspects: selection of chassis cells, screening and expression enhancement of key enzymes, regulation of cofactors, enhancement of precursor supply and promotion of abscisic acid efflux. Finally, the future development direction of this field is prospected.
Abscisic Acid/metabolism* ; Plant Growth Regulators/metabolism* ; Plants/metabolism* ; Yarrowia/metabolism*

Uridine diphosphate glycosyltransferase(UGT) is a highly conserved protein in plants, which usually functions in secondary metabolic pathways. This study used the Hidden Markov Model(HMM) to screen out members of UGT gene family in the whole genome of Dendrobium officinale, and 44 UGT genes were identified. Bioinformatics was used to analyze the structure, phylogeny, and promoter region components of D. officinale genes. The results showed that UGT gene family could be divided into four subfamilies, and UGT gene structure was relatively conserved in each subfamily, with nine conserved domains. The upstream promoter region of UGT gene contained a variety of cis-acting elements related to plant hormones and environmental factors, indicating that UGT gene expression may be induced by plant hormones and external environmental factors. UGT gene expression in different tissues of D. officinale was compared, and UGT gene expression was found in all parts of D. officinale. It was speculated that UGT gene played an important role in many tissues of D. officinale. Through transcriptome analysis of D. officinale mycorrhizal symbiosis environment, low temperature stress, and phosphorus deficiency stress, this study found that only one gene was up-regulated in all three conditions. The results of this study can help understand the functions of UGT gene family in Orchidaceae plants and provide a basis for further study on the molecular regulation mechanism of polysaccharide metabolism pathway in D. officinale.
Dendrobium/genetics* ; Plant Growth Regulators ; Glycosyltransferases/metabolism* ; Gene Expression Profiling ; Mycorrhizae ; Phylogeny ; Plant Proteins/metabolism*

14-3-3 proteins are important proteins in plants, as they regulate plant growth and development and the response to biotic or abiotic stresses. In this study, a 14-3-3 gene(GenBank accession: OM683281) was screened from the cDNA library of the medicinal species Salvia miltiorrhiza by yeast two-hybrid and cloned. The open reading frame(ORF) was 780 bp, encoding 259 amino a cids. Bioinformatics analysis predicted that the protein was a non-transmembrane protein with the molecular formula of C_(1287)H_(2046)N_(346)O_(422)S_9, relative molecular weight of 29.4 kDa, and no signal peptide. Homologous sequence alignment and phylogenetic tree analysis proved that the protein belonged to 14-3-3 family and had close genetic relationship with the 14-3-3 proteins from Arabidopsis thaliana, Oryza sativa, and Nicotiana tabacum. The 14-3-3 gene was ligated to the prokaryotic expression vector pGEX-4 T-1 and then transformed into Escherichia coli BL21 for the expression of recombinant protein. Real-time fluorescent quantitative PCR showed that the expression of this gene was different among roots, stems, leaves, and flowers of S. miltiorrhiza. To be specific, the highest expression was found in leaves, followed by stems, and the lowest expression was detected in flowers. S. miltiorrhiza plants were treated with 15% PEG(simulation of drought), and hormones salicylic acid, methyl jasmonate, and ethephon, respectively, and the expression of 14-3-3 gene peaked at the early stage of induction. Therefore, the gene can quickly respond to abiotic stresses such as drought and plant hormone treatments such as salicylic acid, jasmonic acid, and ethylene. This study lays the foundation for revealing the molecular mechanism of 14-3-3 protein regulating tanshinone biosynthesis and responding to biotic and abiotic stresses.
14-3-3 Proteins/metabolism* ; Amino Acid Sequence ; Cloning, Molecular ; Ethylenes/metabolism* ; Gene Expression Regulation, Plant ; Hormones/metabolism* ; Phylogeny ; Plant Growth Regulators/pharmacology* ; Plant Proteins/metabolism* ; Recombinant Proteins/genetics* ; Salicylic Acid/metabolism* ; Salvia miltiorrhiza/metabolism*

Transcriptional factors play important roles in plant growth, development and responses to stresses. BBX transcriptional factors are characterized with one or two B-box domains in the protein sequence. They are comprehensively involved in photomorphogenesis, flowering, shade avoidance, signal transduction of phytohormones, biotic and abiotic stress responses in plants by regulating gene transcription and interacting with other transcription factors. The classification, structure and functions of BBX of plants are reviewed in this paper.
Gene Expression Regulation, Plant ; genetics ; Plant Growth Regulators ; genetics ; metabolism ; Plant Proteins ; genetics ; metabolism ; Stress, Physiological ; genetics ; Transcription Factors ; genetics ; metabolism

Plant trichomes are special structures that originate from epidermal outgrowths. Trichomes play an important role in plant defense against pests and diseases, and possess economic and medicinal values. Study on molecular mechanism of plant trichomes will contribute to the molecular design breeding and genetic improvement of crops. In recent years, the regulation mechanism of trichome development has been basically clarified in the model plant Arabidopsis thaliana, while great progresses are also found in other plant species. In this review, we focus on the developmental regulation of trichome formation from gene and phytohormones levels in Arabidopsis and cotton (with unicellular trichomes), as well as in tomato and Artemisia annua (with multicellular trichomes). The research progress associated with trichomes is also introduced in other typical monocotyledons and dicotyledons. Finally, the research and application of plant trichomes are prospected.
Arabidopsis/genetics* ; Gene Expression Regulation, Plant ; Gossypium/genetics* ; Lycopersicon esculentum ; Plant Growth Regulators/metabolism* ; Trichomes/genetics*

Anemone flaccida Fr. Schmidt is a perennial medicinal herb that contains pentacyclic triterpenoid saponins as the major bioactive constituents. In China, the rhizomes are used as treatments for a variety of ailments including arthritis. However, yields of the saponins are low, and little is known about the plant's genetic background or phytohormonal responsiveness. Using one-quarter of the 454 pyrosequencing information from the Roche GS FLX Titanium platform, we performed a transcriptomic analysis to identify 157 genes putatively encoding 26 enzymes involved in the synthesis of the bioactive compounds. It was revealed that there are two biosynthetic pathways of triterpene saponins in A. flaccida. One pathway depends on β-amyrin synthase and is similar to that found in other plants. The second, subsidiary ("backburner") pathway is catalyzed by camelliol C synthase and yields β-amyrin as minor byproduct. Both pathways used cytochrome P450-dependent monooxygenases (CYPs) and family 1 uridine diphosphate glycosyltransferases (UGTs) to modify the triterpenoid backbone. The expression of CYPs and UGTs were quite different in roots treated with the phytohormones methyl jasmonate, salicylic acid and indole-3-acetic acid. This study provides the first large-scale transcriptional dataset for the biosynthetic pathways of triterpene saponins and their phytohormonal responsiveness in the genus Anemone.
Anemone ; drug effects ; genetics ; metabolism ; Biosynthetic Pathways ; drug effects ; genetics ; Cytochrome P-450 Enzyme System ; genetics ; metabolism ; Gene Expression Profiling ; Gene Expression Regulation, Plant ; drug effects ; Glycosyltransferases ; genetics ; metabolism ; Oleanolic Acid ; analogs & derivatives ; metabolism ; Plant Growth Regulators ; pharmacology ; Plant Proteins ; genetics ; metabolism ; Plants, Medicinal ; Rhizome ; drug effects ; genetics ; metabolism ; Saponins ; metabolism ; Triterpenes ; metabolism

Using MS as basic medium, supplemented with 1.0 mg · L(-1) IBA, the adventitious roots of Tripterygium wilfordii were induced, and the good adventitious root culture system was established by leaves or callus induced by leaves as explants. The adventitious roots were also induced with 2.0-4.0 mg · L(-1) NAA and the good adventitious root culture system established by using suspension cells from callus as materials to induce adventitious root. The content of triptolide of three adventitious roots culture system were exceeded in the natural root bark. The content of triptolide of AR3 adventitious roots was the highest about 5.3 times as that in the natural root bark. By using 5 L stirred fermentor during pilot enlarge cultivation, compared with 250 mL flask cultivation, the adventitious roots increment and secondary metabolites content per liter medium showed no significant difference. The accomplishment of this analysis laid a foundation by tissue culture production of the secondary metabolites of T. wilfordii.
Culture Media ; chemistry ; metabolism ; Fermentation ; Plant Growth Regulators ; analysis ; metabolism ; Plant Roots ; growth & development ; metabolism ; Tissue Culture Techniques ; instrumentation ; methods ; Tripterygium ; growth & development ; metabolism

Secondary metabolites are the result of that plant interaction with biological and non-biological factors in the long-term evolution process, and play an important role in plant growth, development and physiology. The effective components of medicinal plant are usually the secondary metabolites in plant cells, and the synthesis of them are affected by a variety of factors, such as environmental impact. Acquirement of the secondary metabolites via callus culture has the advantage of low cost and less environmental impact. The synthesis and accumulation of medicinal plant secondary metabolites are not only controlled by light, temperature and pH, but also infected by germplasm, plant growth regulator and elicitor. This article presents a review of the influencing factors, and provides a basis for further study and development.
Light ; Plant Growth Regulators ; metabolism ; Plant Physiological Phenomena ; radiation effects ; Plants ; metabolism ; radiation effects ; Temperature

In order to study the development characteristics of Rehmannia glutinosa tuberous root expansion and reveal the regulation mechanism of the genes related to hormones in this process, R. glutinosa "wen-85" was used as the experimental material in this study. R. glutinosa tuberous roots of different developmental stages were collected to observe phenotype and tissue morphology using resin semi-thin sections method. The genes related to hormone biosynthesis and response were chosen from the transcriptome of R. glutinosa, which was previously constructed by our laboratory, their expression levels at different development stages were measured by real-time quantitative PCR. The results showed that the root development could be divided into six stages: seeding, elongation, pre-expanding, mid-expanding, late-expanding and maturity stage. The anatomic characteristics indicated that the fission of secondary cambium initiated the tuberous root expansion, and the continuous and rapid division of secondary cambium and accessory cambium kept the sustained and rapid expansion of tuberous root. In addition, a large number oleoplasts were observed in root on the semi-thin and ultra-thin section. The quantitative analysis suggested that the genes related to biosynthesis and response of the IAA, CK, ABA,ethylene, JA and EB were up-regulated expressed, meanwhile, GA synthesis and response genes were down-regulated expressed and the genes of GA negative regulation factors were up-regulated expressed. The maximum levels of most genes expression occurred in the elongation and pre-expansion stage, indicating these two stages were the key periods to the formation and development of tuberous roots. Oleoplasts might be the essential cytological basis for the formation and storage of the unique medicinal components in R. glutinosa. The results of the study are helpful for explanation of development and the molecular regulation mechanism of the tuberous root in R. glutinosa.
Gene Expression Regulation, Developmental ; drug effects ; genetics ; Gene Expression Regulation, Plant ; drug effects ; genetics ; Lipid Droplets ; metabolism ; ultrastructure ; Microscopy, Electron, Transmission ; Plant Growth Regulators ; biosynthesis ; pharmacology ; Plant Proteins ; genetics ; metabolism ; Plant Roots ; genetics ; growth & development ; metabolism ; Rehmannia ; genetics ; growth & development ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Time Factors

To achieve sustainable resources use of Polygonum multiflorum, adventitious roots were efficiently induced and cultured by suspension culture. In order to obtain optimal medium for induction adventitious roots from the young stems of P. multiflorum, MS medium was optimized by supplementing with different concentrations of sucrose and plant growth substances. The optimal medium for suspension culture of adventitious roots was determined by orthogonal design. The adventitious roots with suspension culture were subcultured, and the growth curve was also determined. Furthermore, the effective compound in adventitious roots was detected. The result indicated that the optimal medium for efficient induction of adventitious roots was MS medium containing 4% w/v sucrose, supplemented with 2.0 mg x L(-1) NAA, and 0.2 mg x L(-1) 6-BA. The optimal medium for suspension culture of adventitious roots was MS medium containing 3% sucrose, supplemented with 2.0 mg x L(-1) NAA, and 0.2 mg x L(-1) ABT-7.2,3,5,4'-tetrahydroxyl-diphenyl-ethylene-2-O-beta-D-glucoside was detected in adventitious roots, which was effective compound in medicinal material of P. multiflorum. In conclusion, the experiment achieved efficient induction and suspension culture of adventitious roots of P. multiflorum, and laid a foundation for the research on the sustainable use of traditional Chinese medicine resources.
Culture Media ; chemistry ; metabolism ; Plant Growth Regulators ; metabolism ; Plant Roots ; growth & development ; metabolism ; Polygonaceae ; growth & development ; metabolism ; Sucrose ; metabolism ; Tissue Culture Techniques ; methods