Stilbene synthase is a plant-specific polyketide synthase, and plays important roles in diverse metabolic processes. The genomic stilbene synthase gene was cloned from accession "Baihe-35-1" of Chinese wild Vitis pseudoreticulata, and a stilbene synthase of V. pseudoreticulata (VpSTS) transcripts expressed in the grape-powdery mildew interaction were determined by semi-quantitative RT-PCR. To monitor VpSTS expression in plant, the promoter region flanking the 5' VpSTS coding region was isolated from the genomic DNA of Chinese wild V. pseudoreticulata accession Baihe-35-1. Alignment of the VpSTS promoter sequence showed a 56.4% identity to Vitis vinifera. To identify the upstream region of the VpSTS gene required for promoter activity, a series of VpSTS promoter deletion derivatives was constructed. Each deletion construct was analyzed by Agrobacterium-mediated transient transformation in grapevine and tobacco leaves after infection by Uncinula necator and Alternaria alternata. In transiently transformed grapevine leaves, GUS activity was also determined after treatment with salicylic acid (SA) and 4 degrees C cold. Analysis of a series of 5' deletions of the VpSTS promoter in grapevine leaves indicated that the proximal 162 bp from the transcription initiation site was proved to be necessary for establishing both the constitutive and induced pattern of expression.

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The gene encoding stilbene synthase (STS) plays a central role in many biochemical and physiological actions, and its metabolite resveratrol possesses broad-spectrum resistance to pathogens, as well as diverse pharmacological properties, notably an anticancer effect. Here, we report the expression analysis of the gene encoding STS and its promoter function from a powdery mildew (PM)-resistant Chinese wild Vitis pseudoreticulata, and compare it with two PM-susceptible cultivated grapevines, Vitis vinifera cvs. Carignane and Thompson Seedless. We show an unusual expression pattern of STS in V. pseudoreticulata, which differs markedly from that of the cultivated species. Sequence comparisons reveal that the genomic DNA sequences encoding STS in the three grapevines are highly conserved, but a novel residue mutation within the key motif of STS is solely present in V. pseudoreticulata. Moreover, the STS promoter in V. pseudoreticulata displays a significantly different structure from that found in the two V. vinifera. The three promoter-driven GUS differential expression patterns in transformed tobacco plants induced with Alternaria alternata, methyl jasmonate, and wounding indicated that the structurally different STS promoter of V. pseudoreticulata is responsible for its specific regulatory function. We also demonstrate that the expression of STS genes from their native promoters are functional in transformed tobacco and retain pathogen inducibility. Importantly, the genomic DNA-2 of V. pseudoreticulata under its native promoter shows good induction and the maximum level of resveratrol content. These findings further our understanding of the regulation of STS expression in a resistant grapevine and provide a new pathogen-inducible promoter system for the genetic improvement of plant disease resistance.

Abstract:We investigated the effect of magnetic nanoparticles of Fe 3 O 4 (Fe 3 O 4 -MNPs) on the mice immune system. Imprinting control region (ICR) mice were assigned randomly into four groups and treated with normal saline or low, medium, or high doses of Fe 3 O 4 -MNPs, respectively. After intravenous administration of Fe 3 O 4 -MNPs for 72 hours, the peripheral T cells and the induction of primary immune responses in mice were investigated by flow cytometry and determined using enzyme-linked immunosorbent assay, respectively. The results showed that the ratio of spleen to body weight was not different between the experimental groups and control group (P . 0.05). The lymphocyte transformation rates in the suspension of spleen were higher in low-dose group than those in the control group (P , 0.05), while the proliferation of splenocytes was low in the medium and high groups when compared to the control group (P , 0.05). In peripheral blood, both the proportions of subset CD4+ and CD8 + T lymphocytes in the low-dose group were higher than those in the control group, whereas there was no difference in the number of CD4 + T cells between the medium-and low-dose groups. Interestingly, the Nanotechnology offers an efficient alternative for cancer diagnostics and tumor target treatment due to the unique properties of nanostructures, such as large surface-to-volume ratio, porous structure, embedded effect, and size effect, which have been recognized as offering potential promising applications in biomedical engineering. Much effort has been extended to the development of novel nanocomposites and biomaterials for DNA detection, 1 intracellular labeling, 2 drug carrier, 3 cancer targeting, 4 imaging, 5 and so on. Therefore, magnetic nanoparticles of Fe 3 O 4 (Fe 3 O 4 -MNPs) as a kind of biocompatible nanomaterial which is feasible to characterize and easily functionalize, may offer an exciting development toward developing an effective drug delivery system while biocompatible superparamagnetic particles like magnetite could be utilized in tissue-specific release of therapeutic agents and magnetic field assisted radionuclide therapy. [6][7][8][9] As a novel material, though we have already proved that Materials and methods experimental agentsExperimental agents were sourced from the following locations: RPMI1640 (Gibco Chemical Co., Carlsbad, CA, USA); Anti-CD3 (PE-Cy5), Anti-CD4, Anti-CD8 ( Pharmingen, San Diego, CA); Calf serum (Gibco Chemical Co); Enzyme-linked immunosorbent assay kit (Gibco, CA, USA); Con A (Sigma Chemical Co., St Louis, MO, USA). Preparation of Fe 3 O 4 -MNPsBased on our previous studies, 10-11 the synthesis of Fe 3 O 4 -MNPs was prepared by the electrochemical deposition under oxidizing conditions. Before being applied in the present experiment, the magnetite nanoparticles were well-distributed in RPMI-1640 medium freshly added with 10% heated-inactivated fetal bovine serum (FBS) using ultrasound treatment in order to obtain Fe 3 O 4 -MNPs colloidal suspension. Animals and animal careFemale an...

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This study aims to evaluate the multidrug resistance (MDR) reversal activity by magnetic nanoparticles of Fe3O4 (MNPs-Fe3O4) and 5-bromotetrandrine (BrTet) MDR cell line K562/A02 solitarily or symphysially. The proliferation of K562 and K562/A02 cells and the cytotoxicity on peripheral blood mononuclear cells (PMBCs) were evaluated by MTT assay. Cellular accumulation of daunorubicin (DNR) was analyzed by flow cytometry. Real-time polymerase chain reaction and Western blotting analyses were performed to examine the mRNA and protein levels of mdr1, respectively. The results showed that the combination of MNPs-Fe3O4 and BrTet with effective concentrations significantly increased cytotoxicity against MDR cell line K562/A02. Both BrTet and MNPs-Fe3O4 increased the intracellular DNR accumulation in the K562/A02 cell line, and downregulated the level of mdr1 gene and expression of P-glycoprotein. Furthermore, the combination did not have significant cytotoxicity in PMBCs. We propose that MNPs-Fe3O4 conjugated with DNR and BrTet probably have synergetic effects on MDR reversal.

Salinity stress is one of typical abiotic stresses that seriously limit crop production. In this study, a genetic linkage map based on 532 molecular markers covering 1341.1 cM was constructed to identify the loci associated with salt tolerance in Brassica napus. Up to 45 quantitative trait loci (QTLs) for 10 indicators were identified in the F2:3 populations. These QTLs can account for 4.80–51.14% of the phenotypic variation. A major QTL, qSPAD5 on LG5 associated with chlorophyll can be detected in three replicates. Two intron polymorphic (IP) markers in this QTL region were developed successfully to narrow down the QTL location to a region of 390 kb. A salt tolerance related gene Bra003640 was primary identified as the candidate gene in this region. The full length of the candidate gene was 1,063 bp containing three exons and two introns in B. napus L. The open reading frame (ORF) is 867 bp and encodes 287 amino acids. Three amino acid differences (34, 54, and 83) in the conserved domain (B-box) were identified. RT-qPCR analysis showed that the gene expression had significant difference between the two parents. The study laid great foundation for salt tolerance related gene mapping and cloning in B. napus L.

Background This study explored the pharmacokinetic parameters and tissue distribution of magnetic iron oxide nanoparticles (Fe 3 O 4 MNPs) in imprinting control region (ICR) mice. Methods The Fe 3 O 4 MNPs were synthesized by chemical coprecipitation, and their morphology and appearance were observed by transmission electron microscopy. ICR mice were divided into a control group and a Fe 3 O 4 MNP-treated group. Probable target organs in ICR mice were observed, and the pharmacokinetic parameters and biodistribution of Fe 3 O 4 MNPs in tissues were identified using atomic absorption spectrophotometry. Results Fe 3 O 4 MNPs were spherical with a well distributed particle diameter, and were distributed widely in various target organs and tissues including the heart, liver, spleen, lungs, kidneys, brain, stomach, small intestine, and bone marrow. The majority of Fe 3 O 4 MNPs were distributed to the liver and the spleen. Fe 3 O 4 MNP levels in brain tissue were higher in the Fe 3 O 4 MNP-treated group than in the control group, indicating that Fe 3 O 4 MNPs can penetrate the blood–brain barrier. Conclusion These results suggest that the distribution of Fe 3 O 4 MNPs was mostly in the liver and spleen, so the curative effect of these compounds could be more pronounced for liver tumors. Furthermore, Fe 3 O 4 MNPs might be used as drug carriers to overcome physiologic barriers.