The Zinc-Finger Protein ZCCHC3 Binds RNA and Facilitates Viral RNA Sensing and Activation of the RIG-I-like Receptors.

Recognition of viral RNA by the retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) initiates innate antiviral immune response. How the binding of viral RNA to and activation of the RLRs are regulated remains enigmatic. In this study, we identified ZCCHC3 as a positive regulator of the RLRs including RIG-I and MDA5. ZCCHC3 deficiency markedly inhibited RNA virus-triggered induction of downstream antiviral genes, and ZCCHC3-deficient mice were more susceptible to RNA virus infection. ZCCHC3 was associated with RIG-I and MDA5 and functions in two distinct processes for regulation of RIG-I and MDA5 activities. ZCCHC3 bound to dsRNA and enhanced the binding of RIG-I and MDA5 to dsRNA. ZCCHC3 also recruited the E3 ubiquitin ligase TRIM25 to the RIG-I and MDA5 complexes to facilitate its K63-linked polyubiquitination and activation. Thus, ZCCHC3 is a co-receptor for RIG-I and MDA5, which is critical for RLR-mediated innate immune response to RNA virus.

[Gene clone and functional identification of sterol glycosyltransferases from Paris polyphylla var. yunnanensis].

In this study, the authors cloned a glycosyltransferase gene PpUGT2 from Paris polyphylla var. yunnanensis with the ORF length of 1 773 bp and encoding 590 amino acids. The phylogenetic tree revealed that PpUGT2 belonged to the UGT80A subfamily and was named as UGT80A49 by the UDP-glycosyltransferase(UGT) Nomenclature Committee. The expression vector pET28a-PpUGT2 was constructed, and enzyme catalytic reaction in vitro was conducted via inducing protein expression and extraction. With UDP-glucose as sugar donor and diosgenin and pennogenin as substrates, the protein was found with the ability to catalyze the C-3 hydroxyl ß-glycosylation of diosgenin and pennogenin. To further explore its catalytic characteristic, 15 substrates including steroids and triterpenes were selected and PpUGT2 showed its activity towards the C-17 position of sterol testosterone with UDP-glucose as sugar donor. Homology modelling and molecule docking of PpUGT2 with substrates predicted the key residues interacting with ligands. The re-levant residues of PpUGT2-ligand binding model were scanned to calculate the corresponding mutants, and the optimized mutants were obtained according to the changes in binding affinity of the ligand with protein and the surrounding residues within 5.0 Å of ligands, which had reference value for design of the mutants. This study laid a foundation for further exploring the biosynthetic pathway of polyphyllin as well as the structure of sterol glycosyltransferases.

A cycloartenol synthase from the steroidal saponin biosynthesis pathway of Paris polyphylla.

Steroidal saponins named polyphyllin are the major active components of Paris polyphylla. Cycloartenol synthase (CAS) is a key enzyme that catalyzes the formation of the sterol scaffold. In this study, we cloned a putative CAS gene from Paris polyphylla. Heterologous expression in yeast indicated that PpCAS can convert 2,3-oxidosqualene into cycloartenol. qRT-PCR analysis showed that the expression of PpCAS was highest in leaves and lowest in roots. To our best knowledge, this is the first report of the functional characterization of cycloartenol synthase from Paris polyphylla, which lays the foundation for further analysis of the biosynthesis pathway of polyphyllins.[Formula: see text].

[Roles of ERK/JNK in carbon black induced AP-1 cell signaling pathway changes].

OBJECTIVE: To investigate the role of ERK/JNK in the alteration of activator protein-1(AP-1) signaling pathway in human embryonic lung fibroblasts(HELFs) induced by carbon black. METHODS: HELFs were cultured in RPMI 1640 medium containing 0, 15, 30, 60, 120 or 240 µg/mL carbon black for 24 h, and the appropriate dose of carbon black was determined by MTT assay result. HELFs were divided into three groups: HELFs, HELFs transfected with ERK dominant negative mutant plasmid(DN-ERK) and HELFs transfected with JNK dominant negative mutant plasmid(DN-JNK). 100 µg/mL carbon black was used to treat HELFs(CB), DN-ERK HELFs(CB-DN-ERK), DN-JNK HELFs(CB-DN-JNK), and HELFs without any treatment were considered as control group. At 0, 1, 2, 4, 8, 12, 24 and 36 h of CB and control groups HELFs, the western blot was used to detect ERK, p-ERK, JNK, p-JNK, p38, p-p38, c-Jun, p-c-Jun, c-Fos, p-c-Fos protein expression levels, and AP-1 activity was detected by luciferase method. Whereas CB-DN-ERK and CB-DN-JNK HELFs were detected only at 24 h. RESULTS: Compared with the protein expression levels at 0 h, CB group HELFs ERK and p-ERK protein expression increased at each time point, whereas p38 protein expression decreased. AP-1 activity of CB group HELFs was declined to the lowest at 8 h(0.72±0.12), and upregulated to the peak at 36 h(1.38±0.11). CB group HELFs c-Fos, p-c-Fos and c-Jun protein expression levels at each time point from 1 h to 24 h were greater than those of 0 h, and p-c-Jun protein expression levels at 1 h, 2 h, 4 h, 8 h, 36 h were also greater than those of 0 h. CB group HELFs AP-1 activity, ERK, p-ERK, JNK, p-JNK, p38, p-p38, c-Jun, p-c-Jun, c-Fos, p-c-Fos protein expression levels changes followed biphasic patterns. There were no statistically significant differences in AP-1 activity between CB group HELFs(1.03±0.10) and CB-DN-ERK group(1.02±0.04) or CB-DN-JNK group(1.09±0.10) HELFs(t=0.16, P=0.88; t=0.73, P=0.50). However, compared with CB group HELFs, c-Fos(t=5.31, P=0.01), p-c-Fos(t=4.33, P=0.01), p-c-Jun(t=10.95, P& lt; 0.01)in CB-DN-JNK group, and c-Fos protein expression levels in CB-DN-ERK group(t=42.72, P& lt; 0.01)were significantly decreased. CONCLUSION: While carbon black induces HELFs increased protein expression levels of ERK, p-ERK, c-Jun, p-c-Jun, c-Fos and p-c-Fos, JNK may upregulate c-Fos, p-c-Fos, p-c-Jun protein expression levels, and ERK may upregulate c-Fos protein expression level.

SNX8 modulates innate immune response to DNA virus by mediating trafficking and activation of MITA.

MITA (also called STING) is a central adaptor protein in innate immune response to cytosolic DNA. Cellular trafficking of MITA from the ER to perinuclear microsomes after DNA virus infection is critical for MITA activation and onset of innate antiviral response. Here we found that SNX8 is a component of DNA-triggered induction of downstream effector genes and innate immune response. Snx8-/- mice infected with the DNA virus HSV-1 exhibited lower serum cytokine levels and higher viral titers in the brains, resulting in higher lethality. Mechanistically, SNX8 recruited the class III phosphatylinositol 3-kinase VPS34 to MITA, which is required for trafficking of MITA from the ER to perinuclear microsomes. Our findings suggest that SNX8 is a critical component in innate immune response to cytosolic DNA and DNA virus.

Eudesmane-type sesquiterpene diols directly synthesized by a sesquiterpene cyclase in Tripterygium wilfordii.

Cryptomeridiol, a typical eudesmane diol, is the active principle component of the antispasmodic Proximol. Although it has been used for many years, the biosynthesis pathway of cryptomeridiol has remained blur. Among terpenoid natural products, terpenoid cyclases are responsible for cyclization and generation of hydrocarbon backbones. The cyclization is mediated by carbocationic cascades and ultimately terminated via deprotonation or nucleophilic capture. Isoprene precursors are, respectively, converted into hydrocarbons or hydroxylated backbones. A sesquiterpene cyclase in Tripterygium wilfordii (TwCS) was determined to directly catalyze (E,E)-farnesyl pyrophosphate (FPP) to unexpected eudesmane diols, primarily cryptomeridiol. The function of TwCS was characterized by a modular pathway engineering system in Saccharomyces cerevisiae The major product determined by NMR spectroscopy turned out to be cryptomeridiol. This unprecedented production was further investigated in vitro, which verified that TwCS can directly produce eudesmane diols from FPP. Some key residues for TwCS catalysis were screened depending on the molecular model of TwCS and mutagenesis studies. As cryptomeridiol showed a small amount of volatile and medicinal properties, the biosynthesis of cryptomeridiol was reconstructed in S. cerevisiae Optimized assays including modular pathway engineering and the CRISPR-cas9 system were successfully used to improve the yield of cryptomeridiol in the S. cerevisiae The best engineered strain TE9 (BY4741 erg9::Δ-200-176 rox1::mut/pYX212-IDI + TwCS/p424-tHMG1) ultimately produced 19.73 mg/l cryptomeridiol in a shake flask culture.

[Cloning and characterization of a monoterpene synthase gene from Tripterygium wilfordii].

Tripterygium wilfordii is a medicinal plant commonly used in the treatment of rheumatoid arthritis,and with pharmacological activities in anti-tumor and obesity treatment. The known active ingredients in T. wilfordii are mainly terpenoids,but with very low content. Therefore,the analysis of the biosynthesis pathway of terpenoids in T. wilfordii has become a research hotspot to solve the problem of its resources. Terpenoid synthase( TPS) is a key enzyme that catalyzes the formation of a wide variety of terpenoid skeletons. In this study,a gene fragment with an ORF of 1 785 bp was cloned from T. wilfordii. Bioinformatics analysis was performed using NCBI's BLASTP,ProtParam and Interpro online tools and MEGA 6.0 software. The response of this gene to methyl jasmonate was also detected by real-time fluorescent quantitative PCR,and its catalytic function was verified by prokaryotic expression and in vitro enzymatic assay. Bioinformatics analysis indicated that the amino acid sequence encoded by this gene had both N-terminal domain and C-terminal domain of TPS,as well as the DDxx D conserved domain of the class I of TPS family. And Tw MTS gathered together with TPS-b subfamily in the Neighbor-Joining Tree constructed with known homologous TPSs. The results of RT-PCR showed that 50 µmol·L-1 MeJA 12 h could increase the expression of Tw MTS to 735 times in the control group at 12 h,and 1 644 times at 24 h. In addition,in vitro enzymatic reaction results showed that Tw MTS can catalyze the production of ß-citronellol with GPP as substrate,indicating that Tw MTS was a monoterpene synthase. The above results provided a new element for the synthetic biology database of T. wilfordii terpenoids,and laid the foundation for future biosynthesis research.

Cloning and functional analysis of two sterol-C24-methyltransferase 1 (SMT1) genes from Paris polyphylla.

The biosynthetic pathways of phytosterols and steroidal saponins are located in two adjacent branches which share cycloartenol as substrate. The rate-limiting enzyme S-adenosyl-L-methionine-sterol-C24-methyltransferase 1 (SMT1) facilitates the metabolic flux toward phytosterols. It catalyzes the methylation of the cycloartenol in the side chain of the C24-alkyl group, to generate 24(28)-methylene cycloartenol. In this study, we obtained two full-length sequences of SMT1 genes from Pari polyphylla, designated PpSMT1-1 and PpSMT1-2. The full-length cDNA of PpSMT1-1 was 1369 bp long with an open reading frame (ORF) of 1038 bp, while the PpSMT1-2 had a length of 1222 bp, with a 1005 bp ORF. Bioinformatics analysis confirmed that the two cloned SMTs belong to the SMT1 family. The predicted function was further validated by performing in vitro enzymatic reactions, and the results showed that PpSMT1-1 encodes a cycloartenol-C24-methyltransferase, which catalyzes the conversion of cycloartenol to 24-methylene cycloartenol, whereas PpSMT1-2 lacked this catalytic activity. The tissue expression patterns of the two SMTs revealed differential expression in different organs of Paris polyphylla plants of different developmental stage and age. These results lay the foundation for detailed genetic studies of the biosynthetic pathways of steroid compounds, which constitute the main class of active substances found in P. polyphylla.

[DNA molecular identification of Manis pentadactyla].

The study was aimed to establish a stable, accurate site specific PCR identification system to identify Manis pentadactyla and its adulterants using DNA molecular identification. The genomic DNA was extracted from experimental samples using the DNA extraction kit. The Cytb and CO Ⅰ genes were amplified using PCR and sequenced bi-directionally. Obtained sequences were assembled using the BioEdit software. The neighbor-joining tree was constructed by MEGA 6.0. Specific identification primers were designed according to the specific allelets, and PCR reaction system was optimized. The results indicated that the Cytb and CO Ⅰ sequence both were able to be used to identify M. pentadactyla and its adulterants. With the specific primers CO Ⅰ-S10/A5, the M. pentadactyla could be amplified a 400 bp DNA band when the annealing temperature ranged from 55 to 60 ℃ and the amount of DNA template ranged from 3 to 100 ng within 35 PCR cycles. However, other adulterants displayed no relevant bands. So that primers CO Ⅰ- S10 / A5 can be used to identify the M. pentadactyla with the adulterants.

[Cloning and protein expression analysis of geranyl diphosphate synthase genes in Tripterygium wilfordii].

Based on the transcriptome data, the study cloned full-length cDNA of TwGPPS1 and TwGPPS2 genes from Tripterygium wilfordii suspension cells and then analyzed the bioinformation of the sequence and protein expression. The cloned TwGPPS1 has a 1 278 bp open reading frame (ORF) encoding a polypeptide of 425 amino acids. The deduced isoelectric point (pI) was 6.68, a calculated molecular weight was about 47.189 kDa. The full-length cDNA of the TwGPPS2 contains a 1 269 bp open reading frame (ORF) encoding a polypeptide of 422 amino acids. The deduced isoelectric point (pI) was 6.71, a calculated molecular weight was about 46.774 kDa.The entire reading frame of TwGPPS1,2 was cloned into the pET-32a(+) vector and expressed in E. coli BL21 (DE3) cells to obtain the TwGPPS protein, which laid a basis for further study on the regulation of terpenoid secondary metabolism and biological synthesis.

[Cloning and protein expression of sterol-C-24-methyl transferase 2 in Tripterygium wilfordii].

24-Alkyl sterols are the major players in the control of membrane component and plant growth. In this paper, we cloned an important rate-limiting enzyme: sterol-C-24-methyl transferase (SMT) in the sterol biosynthetic pathway according to the transcriptome data of Tripterygium wilfordii. suspension cells, whose full-length cDNA was 1 631 bp with an open reading frame of 1 080 bp, encoding a protein of 359 amino acids. It was estimated that theoretical isoelectric point (p I) was 6.43 and the molecular mass was 40.0 kDa. Bioinformatics analysis attributed the SMT gene to SMT2 family. The expression vector was constructed as the pMAL-c2x-TwSMT2 plasmid and the recombinant protein was expressed in E. coil BL21(DE3) competent cells. After methyl jasmonate treatment, the relative expression level of Tw SMT2 has improved significantly in 24 h. SDS-PAGE electrophoresis and Western Blot showed that protein of TwSMT2 in BL21 (DE3) strain was expressed after induction by IPTG. In this study, TwSMT2 was cloned for the first time and the recombinant protein was expressed, which lay the foundation for elucidation of the sterol biosynthetic pathway of Tripterygium wilfordii in the future.

[Cloning and protein expression of sterol-C-24-methyl transferase 2 in Tripterygium wilfordii].

24-Alkyl sterols are the major players in the control of membrane component and plant growth. In this paper, we cloned an important rate-limiting enzyme: sterol-C-24-methyl transferase (SMT) in the sterol biosynthetic pathway according to the transcriptome data of Tripterygium wilfordii. suspension cells, whose full-length c DNA was 1 631 bp with an open reading frame of 1 080 bp, encoding a protein of 359 amino acids. It was estimated that theoretical isoelectric point (pI) was 6.43 and the molecular mass was 40.0 kDa. Bioinformatics analysis attributed the SMT gene to SMT2 family. The expression vector was constructed as the pMAL-c2x-TwSMT2 plasmid and the recombinant protein was expressed in E. coil BL21(DE3) competent cells. After methyl jasmonate treatment, the relative expression level of TwSMT2 has improved significantly in 24 h. SDS-PAGE electrophoresis and Western Blot showed that protein of TwSMT2 in BL21 (DE3) strain was expressed after induction by IPTG. In this study, Tw SMT2 was cloned for the first time and the recombinant protein was expressed, which lay the foundation for elucidation of the sterol biosynthetic pathway of Tripterygium wilfordii in the future.

Cloning and characterisation of the gene encoding 3-hydroxy-3-methylglutaryl-CoA synthase in Tripterygium wilfordii.

Tripterygium wilfordii is a traditional Chinese medical plant used to treat rheumatoid arthritis and cancer. The main bioactive compounds of the plant are diterpenoids and triterpenoids. 3-Hydroxy-3-methylglutaryl-CoA synthase (HMGS) catalyses the reaction of acetoacetyl-CoA to 3-hydroxy-3-methylglutaryl-CoA, which is the first committed enzyme in the mevalonate (MVA) pathway. The sequence information of HMGS in Tripterygium wilfordii is a basic resource necessary for studying the terpenoids in the plant. In this paper, full-length cDNA encoding HMGS was isolated from Tripterygium wilfordii (abbreviated TwHMGS, GenBank accession number: KM978213). The full length of TwHMGS is 1814 bp, and the gene encodes a protein with 465 amino acids. Sequence comparison revealed that TwHMGS exhibits high similarity to HMGSs of other plants. The tissue expression patterns revealed that the expression level of TwHMGS is highest in the stems and lowest in the roots. Induced expression of TwHMGS can be induced by MeJA, and the expression level is highest 4 h after induction. The functional complement assays in the YML126C knockout yeast demonstrated that TwHMGS participates in yeast terpenoid biosynthesis.

[Effects of ceruloplasmin/PTEN on histone modifications induced by silica].

OBJECTIVE: To explore the roles of ceruloplasmin (Cp) in histone modifications in human embryonic lung fibroblasts (HELFs) induced silica and the effects of phosphatase and tension homolog deleted on chromosome ten (PTEN) in this process. METHODS: HELFs were exposed to different concentrations of silica (50, 100, 200 microg/ ml) or Cp (10, 20, 30 microg/ml) for 24 h, and the level of protein lysine acetylation, of histone H2, H3 and H4 acetylation and histone H3 methylation were checked by werstern blot assay. HELFs and cells transfected with PTEN shRNA (PT) were treated with 200 microg/ml silica for 1 h, then added 30 microg/ml Cp for 24 h. Acetylation levels of protein lysine, histone H2, H3, H4 and methylation level of histone H3 were detected by werstern blot assay. RESULTS: Silica could induce the high level of protein lysine acetylation and acetyl-histone H2B (lys5/12), acetyl-histone H3 (lys9/14), acetyl-histone H4 (lys12) and the low level of methyl-histone (arg2), which could be reversed by Cp, in no exception for acetyl-histone H2B (lys5/12). Cp couldn't reverse histone modifications induced by silica when inhibited PTEN. CONCLUSION: Cp could reverse silica-induced the change of histone acetylation and histone methylation, and PTEN involved in this process.

[Roles of p53 in the interaction of p21 and cell cycle proteins induced by benzo [a] pyrene].

OBJECTIVE: To investigate the roles of p53 in the interaction of p21, cyclin D1 and CDK4 in human embryonic lung fibroblasts (HELFs) induced by benzo (a) pyrene. METHODS: p53-H group (cells transfected with p53 small interference RNA plasmid, p53 siRNA) and HELF/CMV group (cells transfected with CMV vector) were treated with 2 micromol/L B [a] P for 24 h, and HELF/CMV + PFT-alpha group (HELF/CMV cells were treated with p53 chemical inhibitor, Pifithrin-alpha) was treated with 2 micromol/L B [a] P and 20 micromol/L PFT-alpha for 24 h. The above three groups set up control groups, respectively. Western blot assay was used to check the levels of p53, phosphorylated p53 at 20 site (p53-ser20), p21, cyclin D1 and CDK4. Immunoprecipitation assay was used to investigate the roles of p53 in the interaction of p21, cyclin D1 and CDK4. RESULTS: After inhibition of p53 using PFT-alpha or siRNA, the high levels of p53, p53-ser 20 and p21 induced by B [a] P were markedly decreased. The change of cyclin D1 level was not obsevered and the level CDK4 was free of B [a] P. The combination of p21 and CDK 4 was increased after HELFs exposed to B [a] P, which can not be observed after inhibition p53. The combination of p21 and cyclin D1 was increased with or without the expression of p53 after HELFs exposed to B [a] P. The combination of cyclin D1 and CDK 4 was not affected by B [a] P. CONCLUSION: p53 can affect the combination of p21 and CDK4 in HELFs induced by B [a] P.

[Effects on Salvia miltiorrhiza hairy roots of tanshinones content accumulation after treated with fosmidomycin].

Fosmidomycin (100 micromol x L(-1)) which is the effective inhibitor of DXR, key enzyme in terpenoid MEP pathway, was used to treat with hairy roots of Salvia miltiorrhiza. The treated roots were harvested at 2, 4, 6, 8, 10, 16 and 21 d, mRNA level of SmDXR and tanshinone content in treated and negative control groups were detected. Results found that, after treated with fosmidomycin, color of S. miltiorrhiza hairy roots grew pale gradually comparing with controls; mRNA level of SmDXR in hairy roots varied as a shape of parabolic and the highest value achieved at the sixth day after treatment, then it decreased gradually; Content of four kinds of tanshinones were detected. Among of the four kinds of tanshinones, Tanshinone I content changed relatively little, while content of dihydrotanshinone I, cryptotanshinone and tanshinone II (A) decreased gradually in 21 days. The content of total tanshinones in NC groups was 5, 63 times more than FOS-treated roots in the 21th day. The previous results showed that SmDXR played an important role in the accumulation of tanshinone content in MEP pathway. Once the mRNA level of SmDXR was suppressed, the accumulation of secondary metabolites will be significantly affected.

[Advances in studies on 3-hydroxy-3-metllylglutaryl coenzyme A reductase in terpenoids biosynthesis of medicinal plants].

There exists many kinds and a huge number of terpenoid in medicinal plants, which show a wide range of pharmacological activities. 3-Hydroxy-3-metllylglutaryl coenzyme A reductase(HMGR) is a key rate-limiting enzyme in terpenoid biosynthetic pathway . HMGR plays an important role in the regulation of secondary metabolism of the terpenoid. The paper summarized the biological function and the catalytic mechanism of HMGR, the cloning and the structure of the gene as well as its research progress in some medicinal plants.

ß-adrenoreceptor-triggered PKA activation negatively regulates the innate antiviral response.

Upon viral infection, cytoplasmic pattern recognition receptors detect viral nucleic acids and activate the adaptor protein VISA/MAVS- or MITA/STING-mediated innate antiviral response. Whether and how the innate antiviral response is regulated by neuronal endocrine functions is unclear. Here, we show that viral infection reduced the serum levels of the ß-adrenergic hormones epinephrine and norepinephrine as well as the cellular levels of their receptors ADRB1 and ADRB2. We further show that an increase in epinephrine/norepinephrine level inhibited the innate antiviral response in an ADRB1-/2-dependent manner. Mechanistically, epinephrine/norepinephrine stimulation activated the downstream kinase PKA, which catalyzed the phosphorylation of MITA at S241, S243 and T263, inhibiting MITA activation and suppressing the innate immune response to DNA virus. In addition, phosphorylation of VISA at T54 by PKA antagonized the innate immune response to RNA virus. These findings reveal the regulatory mechanisms of innate antiviral responses by epinephrine/norepinephrine and provide a possible explanation for increased host susceptibility to viral infection in stressful and anxiety-promoting situations.

[Cloning and expression analysis of a new 3-hydroxy-3-methylglutaryl coenzyme A reductase gene from Salvia miltiorrhiza (SmHMGR3)].

OBJECTIVE: To clone and analysis a new 3-hydroxy-3methylglutary CoA reductase cDNA from Salvia miltiorrhiza (SmHMGR3). METHOD: Transcription database of S. miltiorrhiza was used and a new regulatory gene from terpene secondary metabolic pathway has been cloned. ORF Finder was used to find the open reading frame of SmHMGR3 cDNA and ClustalW has been performed to analysis the multiple amino acid sequence alignment. Phylogenetic tree has been constructed using MEGA5.0. RT-PCR has been applied to detect the transcription level of SmHMGR3 in roots, stems and leaves from flowering S. miltiorrhiza plant. The mRNA level of SmHMGR3 gene from hairy roots was detected after elicitor Ag+ supplied. RESULT: The SmHMGR3 cDNA sequence was obtained. The total length of SmHMGR3 cDNA was 1,692 bp encoding 563 amino acids. The homology rate was 75.04% and 80.64% comparing with SmHMGR1 and SmHMGR2 respectively. QRT-PCR results showed that the highest mRNA level existed in leaves of S. miltiorrhiza. After induced by Ag for 24h, the transcription level reached the highest value. CONCLUSION: A new SmHMGR3 gene has been obtained for the first time, and which can provide the new target for the further studies about tepenes metabolism.

[Establishment and analysis of in vitro culture system for transgenic Salvia miltiorrhiza hairy roots].

OBJECTIVE: To establish a culture system for transgenic Salvia miltiorrhiza hairy roots. METHOD: Investigated the success rate of different explants, different infection time and different co-culture time to induce hairy roots of S. miltiorrhiza. Co-cultured explants were sterilizated with 400 g x L(-1) Cef water for 5 min, inoculated on MS solid medium supplied with 400 mg x mL(-1) cef and 2.5 g x L(-1) Hyg, and then transfered to the 67-V liquid medium with 2.5 g x L(-1) Hyg after complete sterilization. GFP fluorescence detection was performed to detect positive hairy root lines. PCR method to detect rolC gene which is the specific gene of hairy root. Biomass was determinated in different growth periods of root lines. HPLC was conducted to measure the content of dihydrotanshinone I of transgenic hairy roots. RESULT: Leaf base of S. miltiorrhiza was used as a perfect explant to Induce hairy roots, the success rate can reach 93.3%. Inducing efficiency was up to 63.3% after Agrobacterium infection for 10 min. Co-culture for 2-3 d can reach the best induced effect. It is a high credibiliy to use PCR method combined with detection of GFP fluorescence to identified positive transformants. There is a close contact between biomass increases and secondary metabolite accumulation of transgenic hairy roots. CONCLUSION: Successfully in vitro culture system has been established in transgenic S. miltiorrhiza, and this research can lay foundations for the further genetic engineering applications.