[Accumulation and biosynthetic of curcuminoids and terpenoids in turmeric rhizome in different development periods].

The dynamic accumulation rule of active substances in medicinal plants is of great value not only for medicinal material production and application,but also for the genetic mechanism study on the formation of medicinal ingredients,especially vital to guide medicinal material collection as well as experiment material selection and candidate gene screening in the analysis of biosynthesis pathway. This study investigated the accumulation of curcumins and terpenoids,and the biosynthesis of these metabolites,which are the active metabolites in Curcuma longa,a commonly used traditional Chinese medicine. Rhizoma of C. longa from leaf growing period,rhizome swelling period and dry matter accumulating period were used as experimental materials,to analyze the changes of metabolites and biosynthesis in the three periods by comparative transcriptome and metabolomes analysis.The results indicated that terpenoids accumulation and biosynthesis mainly occurred in leaf growing period,while curcumin accumulation and biosynthesis mainly occurred in dry matter accumulating period. Therefore,we suggested that turmeric rhizomes in leaf growth period were suitable for terpenoids biosynthetic pathway characterization,and rhizome in accumulation of dry matter period was suitable for curcuminoid biosynthesis pathway characterization. This study provides references for medicinal materialproduction and application,as well as biopathway analysis of active compounds for C. longa.

Combination of specific single chain antibody variable fragment and siRNA has a synergistic inhibitory effect on the propagation of avian influenza virus H5N1 in chicken cells.

BACKGROUND: The avian influenza virus (AIV) causes frequent disease with high morbidity and mortality. RNA interference (RNAi) has been shown to provide an effective antiviral defense in animals, and several studies have focused on harnessing small interfering RNAs (siRNAs) to inhibit viral infections. In addition, single chain variable fragments (scFvs) contain the complete antigen binding site, and specific scFvs can bind to and neutralize viruses. RESULTS: Fourteen positive scFvs were selected by the yeast two-hybrid system. Using molecular docking technology, we selected the three highest affinity scFvs for further functional validation. Results of indirect ELISA and IFA showed that all three scFvs could bind to FJ13 strain and had neutralizing activity, decreasing the viral infectivity markedly. Chicken fibroblastic DF-1 cells were transfected with scFvs in combination with siRNA-NP604 (an siRNA of anti-AIV NP protein previously reported). Following infection with FJ13 virus, copy numbers of the virus were significantly reduced from 12 h to at least 60 h post-infection compared to that achieved in cells transfected with scFv or siRNA-NP604 separately. CONCLUSIONS: A novel combination of antiviral siRNAs expressed in chicken cells and chicken antibody single-chain variable fragments (scFvs) secreted from the cells has a synergistic inhibitory effect on the avian influenza viral proliferation in vitro. Intracellular application of scFvs and anti-viral siRNA may provide a new approach to influenza prevention and treatment.

Dodder-transmitted mobile systemic signals activate a salt-stress response characterized by a transcriptome change in Citrus sinensis.

Citrus is an essential horticultural fruit whose yield and quality are affected by salinity all over the world. The recognition and adaptive regulation of citrus against salt stress are important areas for cultivar improvement, but the vascular system signal transduction mechanism of the plant response to salt stress remains elusive. In this study, we constructed a dodder (Cuscuta spp.) linked Hamlin sweet orange (Citrus sinensis) plant community in which deliver a vascular signal through the dodder in response to salt stress. RNA-seq technology was used to analyze the gene expression profile of citrus leaves after salt treatment. The results showed that a vascular signal was transmitted to a dodder-linked host plant, triggering a transcriptional response to salt stress. However, the phenotypic and transudative ability of the dodder changed after 24 h. The salt treatment group (Group S) and the dodder-linked group (Group D) respectively contained 1,472 and 557 differentially expressed genes (DEGs). 454 of which were common to both groups. The results of our analysis revealed that the gene expression categories in Group D represented a highly consistent trend compared to the group S plants, indicating that the dodder-bridged vascular signals activated the stress-response of citrus leaves for transcriptomic reconfiguration. The KEGG pathway database and an analysis of key drivers revealed that phenylpropanoid biosynthesis, photosynthesis-antenna proteins, starch and sucrose metabolism, plant hormone signal transduction, circadian rhythm, and MAPK signaling pathways were significantly enriched as the critical genes during salt stress. A systemic signal in the dodder-bridged host significantly regulated abiotic stress-related secondary metabolic pathways, including those for phenylpropanoids, lignin, and lignans. The physiological indexes of photosynthetic intensity, respiration, and attractiveness among communities supported the transcriptional changes. Thus, our results indicate that salt stress-induced vascular system signals can be transmitted through the vascular system of a dodder linking citrus plants, revealing the genetic regulation and physiological changes of citrus leaves responding to plant stress signal transmission.