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141.
Seo HM  Jung Y  Song S  Kim Y  Kwon T  Kim DH  Jeung SJ  Yi YB  Yi G  Nam MH  Nam J 《Biotechnology letters》2008,30(10):1833-1838
Most high-affinity phosphate transporter genes (OsPTs) in rice were highly induced in roots when phosphate was depleted. OsPT1, however, was highly expressed in primary roots and leaves regardless of external phosphate concentrations. This finding was confirmed histochemically using transgenic rice plants that express the GUS reporter gene under the control of the OsPT1 promoter, which exhibited high GUS activity even in the phosphate sufficient condition. Furthermore, transgenic rice plants overexpressing the OsPT1 gene accumulated almost twice as much phosphate in the shoots as did wild-type plants. As a result, transgenic plants had more tillers than did wild-type plants, which is a typical physiological indicator for phosphate status in rice.  相似文献   
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A bacterium, designated M2-6, was isolated from Korean ginseng, Panax ginseng C. A. Meyer, roots after high-hydrostatic-pressure processing. On the basis of 16 rRNA gene phylogeny, the isolate was presumptively identified as a Bacillus sp. Here we report the draft genome sequence of Bacillus sp. strain M2-6 (= KACC 16563).  相似文献   
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To deploy a high-throughput genotyping platform in germplasm management, we designed and tested a custom OPA (Oligo Pool All), LSGermOPA, for assessing the genetic diversity and population structure of the USDA cultivated lettuce (Lactuca sativa L.) germplasm collection using Illumina’s GoldenGate assay. This OPA contains 384 EST (expressed sequence tag)-derived SNP (single nucleotide polymorphism) markers selected from a large set of SNP markers experimentally validated and mapped by the Compositae Genome Project. Used for genotyping were DNA samples prepared from bulked leaves of five randomly-selected seedlings from each of 380 lettuce accessions. High-quality genotype data were obtained from 354 of the 384 SNPs. The reproducibility of automatic genotype calls was 99.8% as calculated from the four pairs of duplicated DNA samples in the assay. An unexpectedly high percentage of heterozygous genotypes at the polymorphic loci for most accessions indicated a high level of heterogeneity within accessions. Only 148 homogenous accessions, collectively comprising all five horticultural types, were used in subsequent analyses to demonstrate the usefulness of LSGermOPA. The results of phylogenetic relationship, population structure and genetic differentiation analyses were consistent with previous reports using other marker systems. This suggests that LSGermOPA is capable of revealing sufficient levels of polymorphism among lettuce cultivars and is appropriate for rapid assessment of genetic diversity and population structure in the lettuce germplasm collection. Challenges and strategies for effective genotyping and managing lettuce germplasm are discussed.  相似文献   
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Genetic studies in budding and fission yeasts have provided evidence that Rdh54, a Swi2/Snf2-like factor, synergizes with the Dmc1 recombinase to mediate inter-homologue recombination during meiosis. Rdh54 associates with Dmc1 in the yeast two-hybrid assay, but whether the Rdh54–Dmc1 interaction is direct and the manner in which these two recombination factors may functionally co-operate to accomplish their biological task have not yet been defined. Here, using purified Schizosaccharomyces pombe proteins, we demonstrate complex formation between Rdh54 and Dmc1 and enhancement of the recombinase activity of Dmc1 by Rdh54. Consistent with published cytological and chromatin immunoprecipitation data that implicate Rdh54 in preventing the non-specific association of Dmc1 with chromatin, we show here that Rdh54 mediates the efficient removal of Dmc1 from dsDNA. These functional attributes of Rdh54 are reliant on its ATPase function. The results presented herein provide valuable information concerning the Rdh54–Dmc1 protein pair that is germane for understanding their role in meiotic recombination. The biochemical systems established in this study should be useful for the continuing dissection of the action mechanism of Rdh54 and Dmc1.  相似文献   
148.
Green tea is a popular worldwide beverage, and its potential beneficial effects such as anti-cancer and anti-oxidant properties are believed to be mediated by epigallocatechin-3-gallate (EGCG), a major constituent of polyphenols. Recently, it was reported that EGCG might be useful in the prevention or treatment of androgenetic alopecia by selectively inhibiting 5alpha-reductase activity. However, no report has been issued to date on the effect of EGCG on human hair growth. This study was undertaken to measure the effect of EGCG on hair growth in vitro and to investigate its effect on human dermal papilla cells (DPCs) in vivo and in vitro. EGCG promoted hair growth in hair follicles ex vivo culture and the proliferation of cultured DPCs. The growth stimulation of DPCs by EGCG in vitro may be mediated through the upregulations of phosphorylated Erk and Akt and by an increase in the ratio of Bcl-2/Bax ratio. Similar results were also obtained in in vivo dermal papillae of human scalps. Thus, we suggest that EGCG stimulates human hair growth through these dual proliferative and anti-apoptotic effects on DPCs.  相似文献   
149.
Antiallergic effects of Vitis amurensis on mast cell-mediated allergy model   总被引:1,自引:0,他引:1  
In this study, we investigated the effect of the methanol extract of fruits of Vitis amurensis Rupr. (Vitaceae; MEVA) on the mast cell-mediated allergy model and studied the possible mechanism of action. Mast cell-mediated allergic disease is involved in many diseases, such as asthma and sinusitis. The discovery of drugs for the treatment of allergic disease is an important subject in human health. MEVA inhibited compound 48/80-induced systemic reactions and serum histamine release in a dose-dependent manner in mice. MEVA decreased immunoglobulin E (IgE)-mediated local allergic reactions, passive cutaneous anaphylaxis. MEVA dose-dependently reduced histamine release from mast cells activated by compound 48/80 or IgE. The inhibitory effect of MEVA on histamine release was mediated by the modulation of intracellular calcium. In addition, MEVA attenuated the phorbol 12-myristate 13-acetate and calcium ionophore A23187 (PMACI)-stimulated secretion of tumor necrosis factor-alpha, interleukin-6 (IL-6), and IL-8 in human mast cells. The inhibitory effect of MEVA on these proinflammatory cytokines was p38 mitogen-activated protein kinase and nuclear factor-kappaB (NF-kappaB) dependent. Our findings provide evidence that MEVA inhibits mast cell-derived, immediate-type allergic reactions and involvement of proinflammatory cytokines, p38 MAPK, and NF-kappaB in these effects.  相似文献   
150.
The Drosophila phototransduction cascade serves as a paradigm for characterizing the regulation of sensory signaling and TRP channels in vivo . Activation of these channels requires phospholipase C (PLC) and may depend on subsequent production of diacylglycerol (DAG) and downstream metabolites . DAG could potentially be produced through a second pathway involving the combined activities of a phospholipase D (PLD) and a phosphatidic acid (PA) phosphatase (PAP). However, a role for a PAP in the regulation of TRP channels has not been described. Here, we report the identification of a PAP, referred to as Lazaro (Laza). Mutations in laza caused a reduction in the light response and faster termination kinetics. Loss of laza suppressed the severity of the phenotype caused by mutation of the DAG kinase, RDGA , indicating that Laza functions in opposition to RDGA. We also showed that the retinal degeneration resulting from overexpression of the PLD was suppressed by elimination of Laza. These data demonstrate a requirement for a PLD/PAP-dependent pathway for achieving the maximal light response. The genetic interactions with both rdgA and Pld indicate that Laza functions in the convergence of both PLC- and PLD-coupled signaling in vivo.  相似文献   
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