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Plant-derived monoterpene indole alkaloids (MIAs) from Uncaria rhynchophylla (UR) have huge medicinal properties in treating Alzheimer's disease, Parkinson's disease, and depression. Although many bioactive UR-MIA products have been isolated as drugs, their biosynthetic pathway remains largely unexplored. In this study, untargeted metabolome identified 79 MIA features in UR tissues (leaf, branch stem, hook stem, and stem), of which 30 MIAs were differentially accumulated among different tissues. Short time series expression analysis captured 58 pathway genes and 12 hub regulators responsible for UR-MIA biosynthesis and regulation, which were strong links with main UR-MIA features. Coexpression networks further pointed to two strictosidine synthases (UrSTR1/5) that were coregulated with multiple MIA-related genes and highly correlated with UR-MIA features (r > 0.7, P < 0.005). Both UrSTR1/5 catalyzed the formation of strictosidine with tryptamine and secologanin as substrates, highlighting the importance of key residues (UrSTR1 : Glu309, Tyr155; UrSTR5 : Glu295, Tyr141). Further, overexpression of UrSTR1/5 in UR hairy roots constitutively increased the biosynthesis of bioactive UR-MIAs (rhynchophylline, isorhynchophylline, corynoxeine, etc), whereas RNAi of UrSTR1/5 significantly decreased UR-MIA biosynthesis. Collectively, our work not only provides candidates for reconstituting the biosynthesis of bioactive UR-MIAs in heterologous hosts but also highlights a powerful strategy for mining natural product biosynthesis in medicinal plants. [ABSTRACT FROM AUTHOR]

Bioactive terpenoids from Curcuma wenyujin (CW), as specialized metabolites, have huge medicinal properties. Accumulating evidence suggested that Jasmonates (JAs) and abscisic acid (ABA) shake hands and coordinately control a wide range of plant growth and defense activities, including the production of specialized metabolites. However, knowledge of how JA and ABA signalings interact to regulate terpenoid biosynthesis (TBS) is limited. In this study, integrative transcriptome and metabolome analyses revealed that exogenous methyl jasmonate (MeJA) and ABA activate the biosynthesis of terpenoids by upregulating the expressions of genes related to the TBS pathway, JA and ABA responses. Most of the differentially changed terpenoids and transcripts were commonly induced by MeJA and ABA. Interactive networks of "gene-gene/metabolite" indicated that CwbHLH2 , a MeJA and ABA dual-responsive regulator, is tightly related to terpenoid production. Furthermore, transgenic experiments revealed that overexpression and RNA interference of CwbHLH2 upregulated and downregulated the contents of representative terpenoids in the MeJA- and ABA-treated transgenic hairy roots, respectively, with 1.52–3.06-fold increases and 29.6–68.7% reduction. Importantly, the genetic transformation of CwbHLH2 enhanced the expressions of multiple TBS pathway genes and bidirectionally enlarged the JA and ABA signalings caused by MeJA or ABA, demonstrating that CwbHLH2 plays a critical interrelational role in integrating MeJA- and ABA-induced TBS regulation. Altogether, our results not only advance a new view of the crosstalk between JA and ABA in modulating TBS but also provide a powerful strategy for improving the yield of bioactive terpenoids in CW. [Display omitted] • MeJA and ABA significantly activate the accumulation of terpenoids in C. wenyujin leaves. • MeJA and ABA coregulate wide transcriptional changes to steer terpenoid formation. • CwbHLH2 plays a critical interrelational role in integrating JA and ABA signalings. • CwbHLH2 promotes MeJA- and ABA-inducible defense responses. • CwbHLH2 provides a powerful tool for improving the yield of terpenoids in Curcuma. [ABSTRACT FROM AUTHOR]

Plant JASMONATE ZIM‐DOMAIN (JAZ) genes play crucial roles in regulating the biosynthesis of specialized metabolites and stressful responses. However, understanding of JAZs controlling these biological processes lags due to numerous JAZ copies. Here, we found that two leaf‐specific CwJAZ4/9 genes from Curcuma wenyujin are strongly induced by methyl‐jasmonate (MeJA) and negatively correlated with terpenoid biosynthesis. Yeast two‐hybrid, luciferase complementation imaging and in vitro pull‐down assays confirmed that CwJAZ4/9 proteins interact with CwMYC2 to form the CwJAZ4/9‐CwMYC2 regulatory cascade. Furthermore, transgenic hairy roots showed that CwJAZ4/9 acts as repressors of MeJA‐induced terpenoid biosynthesis by inhibiting the terpenoid pathway and jasmonate response, thus reducing terpenoid accumulation. In addition, we revealed that CwJAZ4/9 decreases salt sensitivity and sustains the growth of hairy roots under salt stress by suppressing the salt‐mediated jasmonate responses. Transcriptome analysis for MeJA‐mediated transgenic hairy root lines further confirmed that CwJAZ4/9 negatively regulates the terpenoid pathway genes and massively alters the expression of genes related to salt stress signaling and responses, and crosstalks of multiple phytohormones. Altogether, our results establish a genetic framework to understand how CwJAZ4/9 inhibits terpenoid biosynthesis and confers salt tolerance, which provides a potential strategy for producing high‐value pharmaceutical terpenoids and improving resistant C. wenyujin varieties by a genetic approach. Summary statement: CwJAZ4/9 interacts with CwMYC2 and negatively regulates MeJA‐induced terpenoid biosynthesis by inhibiting jasmonate response in Curcuma wenyujin. Meanwhile, CwJAZ4/9 can confer salt tolerance and sustain hairy root growth by weakening the salt‐mediated JA response and upregulating the expression of stress‐responsive genes. [ABSTRACT FROM AUTHOR]

Background: Anemarrhenae rhizoma (AR) is widely used for the treatment of febrile diseases, cough, and diabetes in traditional Chinese medicines. AR mainly contains flavonoids and steroidal saponins, such as neomangiferin, mangiferin, timosaponin BII, timosaponin BIII, and timosaponin AIII, which showed various biological activities. Objective: The main objective of the study is to establish an ultra-high-performance liquid chromatography-tandem mass spectrometry (MS/MS) method to determine the concentrations of five bioactive constituents in rats' plasma and various tissues. Materials and Methods: The analytes were separated on a C18reversed-phase column. A triple-quadrupole MS/MS equipped with an electrospray ionization source was used as a detector. The main pharmacokinetic parameters were estimated with Drug and Statistics 2.0 Software Package. Results: Neomangiferin and mangiferin exhibit poor oral absorption and slow clearance from the body. Timosaponin BII and timosaponin BIII could be quickly absorbed into the blood circulation and showed double plasma concentration peaks. Timosaponin AIII exhibited a single peak in the plasma concentration-time plot and pharmacokinetic parameters of timosaponin AIII indicated slower absorption, longer body residence time, and slower elimination than timosaponin BII and timosaponin BIII. The five analytes were widely distributed to most of the tissues. Neomangiferin and mangiferin exhibited the maximum concentration in the lung at 6 h after oral administration, the highest levels of timosaponin BII and timosaponin BIII were also observed in the lung at 1 h after oral administration, and the maximum concentration of timosaponin AIII was observed in the liver. Conclusion: The findings of the present study might be helpful to better understand the pharmacokinetics and distribution of AR bioactive constituents in vivo, which would facilitate the clinical application of AR. [ABSTRACT FROM AUTHOR]

Peroxiredoxin (Prx) family members play a critical role in host defense against oxidative stress, and are also involved in immune responses following microbial infection. In the present study, we firstly cloned the cDNA of Peroxiredoxin 5 from Procambarus clarkii (denoted as PcPrx5 ) and investigated its immune functions towards LPS and Poly I:C exposure. The PcPrx5 cDNA was composed of 564 bp and consisting of 187 amino acid residues which included Prx5-like subfamily domain, AHP1 domain and Redoxin domain. The recombinant protein was expressed in Escherichia coli (Transetta DE3), and anti-Prx5 antibodies were prepared. Tissue specific expression analysis showed that PcPrx5 was ubiquitously expressed in all examined tissues. Further, its mRNA transcript was greatest in hepatopancrease, haemocyte followed by gut and stomach, and was weak in muscle. The LPS and Poly I:C exposure could both significantly up-regulate the transcript level of PcPrx5 , however the expression trends were different following LPS and Poly I: C treatments. Further, we investigated the antioxidant role of recombinant PcPrx5 protein in vitro by mixed-function oxidase assay; the results demonstrated a dose-dependent inhibition of DNA damage by PcPrx5. Our results implicate PcPrx5 as an important defense against microbial pathogens and oxidants in P. clarkii . [ABSTRACT FROM AUTHOR]

The RNA-sequencing followed by de novo assembly generated 61,912 unigene sequences of P. clarkii hepatopancreas. Comparison of gene expression between LPS challenged and PBS control samples revealed 2552 differentially expressed genes (DEGs). Of these sequences, 1162 DEGs were differentially up-regulated and 1360 DEGs differentially down-regulated. The DEGs were then annotated against gene ontology (GO) database and Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Some immune-related pathways such as PPAR signaling pathway, lysosome, Chemical carcinogenesis, Peroxisome were predicted by canonical pathways analysis. The reliability of transcriptome data was validated by quantitative real time polymerase chain reaction (qRT-PCR) for the selected genes. The data presented here shed light into antibacterial immune responses of crayfish. In addition, these results suggest that transcriptomic data provides valuable sequence resource for immune-related gene identification and helps to understand P. clarkii immune functions. [ABSTRACT FROM AUTHOR]

Abstract: We report the effects of hydrogen sulfide (H2S) on flower senescence in various species of cut flowers. H2S was found to delay flower opening and senescence in cut flowers and branches from Erigeron annuus (L.), Euonymus maackii Rupr., Hibiscus syriacus L., Liriope spicata (Thump.), Loropetalum chinense (R. Br.), Punica granatum L., Rosa chinensis Jacq., and Salix matsudana Koidz. Cut explants of these plants were cultured in solution containing different concentrations of the H2S donor, NaHS. H2S donor treatment prolonged the vase time of cut flowers and prevented senescence in a dose-dependent manner. We measured the levels of malondialdehyde (MDA) as an indicator of oxidative damage to cells and showed that it was inversely related to endogenous H2S concentration in explants. Flowers that had senesced showed higher levels of MDA and lower amounts of H2S. Furthermore, NaHS treatment increased the activities of catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX) and guaiacol peroxidase (POD), and sustained much lower levels of H2O2 and O2 − in cut flowers of E. annuus and explant leaves of S. matsudana. The present study implies that H2S is involved in improving longevity of cut flowers and functions in activity of antioxidant enzymes in plants. [Copyright &y& Elsevier]

Abstract: We describe a visible dye-based staining method for DNA in polyacrylamide gels using ethyl violet (EV). The novel method is a background-free, sensitive, economical, and simple procedure involving only staining and washing steps that can be completed within 30 min. As little as 0.8–1.6ng of φX174 DNA/HaeIII can be detected by EV, which is about eightfold more sensitive than Nile blue (NB) stain and twofold less sensitive than ethidium bromide (EB) stain. [Copyright &y& Elsevier]