• Mycobiology
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• v.38 no.2
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• pp.144-148
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• 2010

$\beta$-Glucans have been known to exhibit antitumor activities by potentiating host immunity by an unknown mechanism. The C-type lectin dectin-1, a $\beta$-glucan receptor, is found on the macrophage and can recognize various $\beta$-glucans. Previously, we demonstrated the presence of $\beta$-glucan receptor, dectin-1, on the Raw 264.7 cells as well as on murine mucosal organs, such as the thymus, the lung, and the spleen. In order to investigate immunopotentiation of innate immunity by $\beta$-glucan, we stimulated a murine macrophage Raw 264.7 cell line with $\beta$-glucans from Pleurotus ostreatus, Saccharomyces cerevisiae, and Laminaria digitata. Then, we analyzed cytokines such as tumor necrosis factor (TNF)-$\alpha$ and interleukin (IL)-6 by reverse transcription-polymerase chain reaction (RT-PCR). In addition we analyzed gene expression patterns in $\beta$-glucan-treated Raw 264.7 cells by applying total mRNA to cDNA microarray to investigate the expression of 7,000 known genes. When stimulated with $\beta$-glucans, the macrophage cells increased TNF-$\alpha$ expression. When co-stimulation of the cells with $\beta$-glucan and lipopolysaccharide (LPS), a synergy effect was observed by increased TNF-$\alpha$ expression. In IL-6 expression, any of the $\beta$-glucans tested could not induce IL-6 expression by itself. However, when co-stimulation occurred with $\beta$-glucan and LPS, the cells showed strong synergistic effects by increased IL-6 expression. Chip analysis showed that $\beta$-glucan of P. ostreatus increased gene expressions of immunomodulating gene families such as kinases, lectin associated genes and TNF-related genes in the macrophage cell line. Induction of TNF receptor expression by FACS analysis was synergized only when co-stimulated with $\beta$-glucan and LPS, not with $\beta$-glucan alone. From these data, $\beta$-glucan increased expressions of immunomodulating genes and showed synergistic effect with LPS.

• Journal of Plant Biotechnology
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• v.5 no.4
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• pp.209-214
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• 2003

Expression of 43 flowering-related genes was examined in two inbred lines of Chinese cabbage, Chiifu and Kenshin, under different photoperiod, vernalization and flower development stages. The floral genes cloned by RT-PCR with degenerated primers showed high homology with Arabidopsis counterparts. Genes in two inbred lines, TOC, CRY1, CO, RGAL and GAl, were highly expressed under all tested conditions. However, expression of three genes was regulated by particular experimental conditions. The expression of LHY gene was predominant in Chiifu under the short-day conditions, whereas the expression of RGAL gene was influenced by vernalization in both inbred lines. Besides, the expression of NAP gene was induced by vernalization only in Chiifu. Most of the flower identity-related genes were expressed during flower development. The transcript level for several genes was not detected in this experiment.

• Preventive Nutrition and Food Science
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• v.5 no.4
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• pp.184-188
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• 2000

HMG-CoA reductase is th rate-limiting enzyme of cholesterol biosynthesis. As intracellular levels of cholesterol should be regulated elaborately in response to external stimuli an internal needs, the expression of the HMG-CoA reductase gene is regulated intricately at several different levels from transcription to post-translational modification. In this study, we investigated the regulatory mechanism of HMG-CoA reductase gene expression at the post-transcriptional/pre-translational levels in a baby hamster kidney cell line, C100. when 25-hydroxycholesterol was added to cells cultured in medium containing 5% delipidized fetal bovine serum and 25$\mu$M lovastatin, the levels of HMG-CoA reductase mRNA decreased rapidly, which seemed to be due to the increased degradation of reductase mRNA. These suppressive effects of 25-hydroxycholesterol on MG-CoA reductase mRNA levels were blocked by a translation inhibitor, cycloheximide. Similarly, actinomycin D and 5,6-dichloro-1-$\beta$-D-ribofuranosylbenzimidazole, transcription inhibitors, blocked the 25-hydroxycholesterol-mediated degradation of HMG-CoA reductase mRNA. These results indicate that new protein/RNA synthesis is required for the degradation of HMG-CoA reductase mRNA. In addition, data from the transfection experiments shows that cis-acting determinants, regulating the stability of reductase mRNA, were scattered in the sequence corresponding to 1766-4313 based on the sequence of Syrian hamster HMG-CoA reductase cDNA. Our data suggests that sterol-mediated destabilization of reductase mRNA might be one of the important regulatory mechanism of HMG-CoA reductase gene expression.

• Journal of Ginseng Research
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• v.44 no.5
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• pp.747-755
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• 2020

Background: Ginsenosides accumulation responses to temperature are critical to quality formation in cold-dependent American ginseng. However, the studies on cold requirement mechanism relevant to ginsenosides have been limited in this species. Methods: Two experiments were carried out: one was a multivariate linear regression analysis between the ginsenosides accumulation and the environmental conditions of American ginseng from different sites of China and the other was a synchronous determination of ginsenosides accumulation, overall DNA methylation, and relative gene expression in different tissues during different developmental stages of American ginseng after experiencing different cold exposure duration treatments. Results: Results showed that the variation of the contents as well as the yields of total and individual ginsenosides Rg1, Re, and Rb1 in the roots were closely associated with environmental temperature conditions which implied that the cold environment plays a decisive role in the ginsenoside accumulation of American ginseng. Further results showed that there is a cyclically reversible dynamism between methylation and demethylation of DNA in the perennial American ginseng in response to temperature seasonality. And sufficient cold exposure duration in winter caused sufficient DNA demethylation in tender leaves in early spring and then accompanied the high expression of flowering gene PqFT in flowering stages and ginsenosides biosynthesis gene PqDDS in green berry stages successively, and finally, maximum ginsenosides accumulation occurred in the roots of American ginseng. Conclusion: We, therefore, hypothesized that cold-induced DNA methylation changes might regulate relative gene expression involving both plant development and plant secondary metabolites in such cold-dependent perennial plant species.

• BMB Reports
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• v.42 no.4
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• pp.217-222
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• 2009

Controlled gene expression in specific cells is a valuable tool for gene therapy. We attempted to determine whether the lentivirus-mediated Tet-On inducible system could be applied to cancer gene therapy. In order to select the genes that induce cancer cell death, we compared the ability of the known pro-apoptotreic genes, Bax and tBid, and a cell cycle inhibitor, p21cip1/waf1, and determined that Bax was the most effective. For the cancer cell-specific expression of $rtTA2^S$-M2, we tested the matrix metalloproteinase-2 (MMP-2) promoter and determined that it is highly expressed in cancer cell lines, including SNU475 cells. The co-transduction of two lentiviruses that contain sequences for TRE-Bax and $rtTA2^S$-M2, the expression of which is controlled by the MMP-2 promoter, resulted in the specific cell death of SNU475, whereas other cells with low MMP-2 expression did not evidence significant cell death. Our data indicate that the lentivirus-mediated Tet-On system using the cancer-specific promoter is applicable for cancer gene therapy.

• Development and Reproduction
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• v.3 no.1
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• pp.59-67
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• 1999

To investigate the role of interleukin-l$\beta$ (IL-1$\beta$) in the embryonic development, in vivo and in vitro expression patterns of IL-1$\beta$ gene in the preimplantation mouse embryos were examined by RT-PCR, and the effects of explanted mouse ovi-duct and uterine epithelial cells on the expression of IL-1$\beta$ gene in the pleimplantation mouse embryos were examined by co-culture. IL-1$\beta$ mRNA was detected in the embryos from 4-cell stage to blastocyst stage in vivo and from morula stage to hatching blastocyst stage in vitro. This transcript was not detected from the GV stage to late 2-cell stage in vivo, and not at the 4-cell and 8-cell stages in vitro. For the co-culture of late 2-cell embryos with the explanted mouse oviduct and uterine epithelial cells, oviducts and uterine epithelial cells were isolated at 48 hour alter the hCG injection. The explanted oviduct and uterine epithelial cells in co-culture groups facilitated the IL-1$\beta$ gene expression of the mouse embryos in comparison with the control. Taken together these results suggest that the presence of IL-1$\beta$ plays an important role in preimplantation embryonic development. In addition, the up-regulation of IL-1$\beta$ gene expression by the explanted oviduct and uterine epithelial cells demonstrates that embryonic expression of IL-l$\beta$ gene may be regulated by the interaction with oviductal and uterine factor (s).

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.3
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• pp.404-412
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• 2016

We hypothesized that supplementing finishing diets with palm oil would promote adipogenic gene expression and stearoyl-CoA desaturase (SCD) gene expression in subcutaneous (s.c.) and intramuscular (i.m.) adipose tissues of feedlot steers. Eighteen Angus and Angus crossbred steers were assigned to three groups of 6 steers and fed a basal diet (control), with 3% palm oil, or with 3% soybean oil, for 70 d, top-dressed daily. Tailhead s.c. adipose tissue was obtained by biopsy at 14 d before the initiation of dietary treatments and at 35 d of dietary treatments. At slaughter, after 70 d of dietary treatment, tailhead s.c. adipose tissue and i.m. adipose tissue were obtained from the longissimus thoracis muscle. Palm oil increased plasma palmitic acid and soybean oil increased plasma linoleic acid and ${\alpha}$-linolenic acid relative to the initial sampling time. Expression of AMP-activated protein kinase alpha ($AMPK{\alpha}$) and peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) increased between the initial and intermediate biopsies and declined thereafter (p<0.03). SCD gene expression did not change between the initial and intermediate biopsies but declined by over 75% by the final period (p = 0.04), and G-coupled protein receptor 43 (GPR43) gene expression was unaffected by diet or time on trial. Soybean oil decreased (p = 0.01) $PPAR{\gamma}$ gene expression at the intermediate sample time. At the terminal sample time, $PPAR{\gamma}$ and SCD gene expression was less in i.m. adipose tissue than in s.c. adipose tissue (p<0.05). $AMPK{\alpha}$ gene expression was less in s.c. adipose tissue of palm oil-fed steers than in control steers (p = 0.04) and CCAAT enhancer binding protein-beta ($CEBP{\beta}$) gene expression was less in s.c. and i.m. adipose tissues of palm oil-fed steers than in soybean oil-fed steers (p<0.03). Soybean oil decreased SCD gene expression in s.c. adipose tissue (p = 0.05); SCD gene expression in palm oil-fed steers was intermediate between control and soybean oil-fed steers. Contrary to our original hypothesis, palm oil did not promote adipogenic gene expression in s.c. and i.m. adipose tissue.

• Journal of Plant Biotechnology
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• v.7 no.1
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• pp.37-43
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• 2005

Explants of button daisy were screened for their regeneration potential and transient GUS gene expression. Medium containing MS salts minerals and $B_5$ vitamins supplemented with $0.1\;\cal{mg/L}$ BA and $0.1\;\cal{mg/L}$ TDZ showed the best regeneration. Disc florets and receptacles were the most responsive explants in regeneration and transient gene expression respectively. Regenerated plants were successfully rooted and established in the green-house conditions. Infection and co-cultivation of explants with Agrobacterium tumefaciens containing pCAMBIA 1301 resulted in transient GUS foci. Among the different explants, receptacles showed the highest percentage of transient GUS gene expression. Enzymatic and molecular analyses of transformed calli confirmed the integration of GUS gene.

• Journal of Microbiology and Biotechnology
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• v.18 no.1
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• pp.135-137
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• 2008

The metabolic engineering of epothilones, as secondary metabolites, was investigated using Sorangium cellulosum to achieve the selective production of epothilone B, a potent anticancer agent. Thus, the propionyl-CoA synthetase gene (prpE) from Ralstonia solanacearum was heterologously expressed in S. cellulosum to increase the production of epothilone B. Propionyl-CoA synthetase converts propionate into propionyl-CoA, a potent precursor of epothilone B. The recombinant S. celluloslim containing the prpE gene exhibited a significant increase in the resolution of epothilones B/A, with an epothilone B to A ratio of 127 to 1, which was 100 times higher than that of the wild-type cells, demonstrating its potential use for the selective production of epothilone B.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.4
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• pp.301-305
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• 2001

The co-expression of the arg U gene in a double-vector expression system of recombi-nant Escherichia coli BL22(DE3)[pET-IEN2a+pAC-argU] significantly enhanced the production level of reconminant human interferon -$\alpha$2a(rhIFN-$\alpha$2a) in high cell density cultures, compared to a recombinant E. coli culture containing only the single expression vector, pET-IEN2a. The dry cell mass concentration increased to almost 100 g/L, and more than 4 g/L of rhIFN-$\alpha$2a was accumu-lated in the culture broth. Evidently, the synthesis of rhIFN-$\alpha$2a was strongly dependent on the pre-induction growtih rate and more efficient at a higher specific growth rate. The additional sup-ply of tRN $A^{Arg(AGG/AGA)}$ enhanced the expression level of the rhIFN-$\alpha$2a gene in the early stage of the post-induction phase, yet thereafter the specific production rate of rhIFN-$\alpha$2a rapidly de-creased due to severe segregational instability of plasmid vector pET-IEN2a. It would appear that the plasmid instability with only occurred to pET-IEN2a in the double vector system, was re-lated to the effect of translational stress due to the over expression of rhIFN-$\alpha$2a.