• Journal of Applied Biological Chemistry
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• v.62 no.1
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• pp.1-6
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• 2019

The flavonoid, isokaempferide, has various biological activities such as hepatoprotective, antimicrobial and antiproliferative effect and is extracted from Amburana cearensis and Cirsium rivulare (Jacq.). Biotransformation is an alternative tool for the synthesis of value-added flavonoids with inexpensive substrates. Here, to synthesize isokaempferide from naringenin, two genes, PFLS and Rice O-mthyltransferae-9 were introduced in Escherichia coli. Although isokaempferide was successfully synthesized, the amount of biosynthesis was no high. In order to increase the yields of isokaempferide, S-adenosylmethionine (SAM) used as a methyl donor was increased by deleting MetJ, which is a transcriptional regulator related to SAM biosynthetic pathway. Next we optimized the cell concentration and substrate feed concentration with the engineered E. coli strain. Through these strategies, the biosynthesis of isokaempferide was increased up to 87 mg/L.

• Reproductive and Developmental Biology
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• v.35 no.3
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• pp.281-285
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• 2011

In the present study, we identified differentially methylated region (DMR) upstream of Dnmt1o and Dnmt1s gene in early porcine embryos. Porcine Dnmt1o had at least one DMR which was located between -530 bp to -30 bp upstream from transcription start site of the Dnmt1o gene. DNA methylation analyses of Dnmt1o revealed the DMR to be hypomethylated in oocytes, whereas it was highly methylated in sperm. Moreover, the DMR upstream of Dnmt1o was gradually hypermethylated from oocytes to two cells and dramatically changed in the methylation pattern from four cells to BL stages in an in vivo. In an IVF, the methylation status in the DMR upstream of Dnmt1o was hypermethylated from one cell to eight cells, but demethylated at the Morula and BL stages, indicating that the DNA methylation pattern in the Dnmt1o upstream ultimately changed from stage to stage before the implantation. Next, to elucidate whether DNA methylation status of Dnmt1s upstream is stage-by-stage changed in during porcine early development, we analyzed the dynamics of the DNA methylation status of the Dnmt1s locus in germ cell, or one cell to BL cells. The Dnmt1s upstream was highly methylated in one and eight cells, while less methylated in two, four, morula, and BL cells. Taken together, our data demonstrated that DNA methylation and demethylation events in upstream of Dnmt1o/Dnmt1s during early porcine embryos dramatically occurred, and this change may contribute to the maintenance of genomewide DNA methylation in early embryonic development.

• BMB Reports
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• v.45 no.3
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• pp.200-205
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• 2012

Enzymatic oxidation of commercially available pyrogallol was efficiently transformed to an oxidative product, purpurogallin. Purpurogallin plays an important role in inhibiting glutathione S-transferase, xanthine oxidase, catechol O-methyltransferase activities and is effective in the cell protection of several cell types. However, the anti-inflammatory functions of purpurogallin are not well studied. Here, we determined the effects of purpurogallin on lipopolysaccharide (LPS)-mediated proinflammatory responses. The results showed that purpurogallin inhibited LPS-mediated barrier hyper-permeability, monocyte adhesion and migration and such inhibitory effects were significantly correlated with the inhibitory functions of purpurogallin on LPS-mediated cell adhesion molecules (vascular cell adhesion molecules, intracellular cell adhesion molecule, E-selectin). Furthermore, LPS-mediated nuclear factor-${\kappa}B$ (NF-${\kappa}B$) and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) releases from HUVECs were inhibited by purpurogallin. Given these results, purpurogallin showed its anti-inflammatory activities and could be a candidate as a therapeutic agent for various systemic inflammatory diseases.

• Journal of Plant Biotechnology
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• v.3 no.3
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• pp.135-140
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• 2001

An Agrobacterium tumefaciens LBA4404 (harboring antisense OMT gene)-mediated transformation method has been developed for poplar (P.nigra x maximowiczii) using prolonging co-cultivation time. Explants on LT (longterm) were induced transgenic calli one month earlier than those from ST (short-term) co-cultivation and remained healthier on LT than ST. With this approach, LT method reduced time to produce transgenic calli. Shoots were successfully regenerated from transgenic calli on SIM (Shoot Induction Medium) and rooted well on the basal medium spontaneously. The presence of antisense OMT gene was verified both by PCR and Southern analysis. Each transgenic poplar was phenotypically indishtinguishable when compared with controls for their growth pattern, leaf morphologies and xylem coloration.

• The Plant Pathology Journal
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• v.24 no.1
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• pp.8-16
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• 2008

Aurofusarin is a polyketide pigment produced by some Fusarium species. The PKS12 and GIP1 genes, which encode a putative type I polyketide synthase (PKS) and a fungal laccase, respectively, are known to be required for aurofusarin biosynthesis in Gibberella zeae (anamorph: Fusarium graminearum). The ten additional genes, which are located within a 30 kb region of PKS12 and GIP1 and regulated by a putative transcription factor (GIP2), organize the aurofusarin biosynthetic cluster. To determine if they are essential for aurofusarin production in G. zeae, we have employed targeted gene deletion, complementation, and chemical analyses. GIP7, which encodes O-methyltransferase, is confirmed to be required for the conversion of norrubrofusarin to rubrofusarin, an intermediate of aurofusarin. GIP1-, GIP3-, and GIP8-deleted strains accumulated rubrofusarin, indicating those gene products are essential enzymes for the conversion of rubrofusarin to aurofusarin. Based on the phenotypic changes in the gene deletion strains examined, we propose a possible pathway for aurofusarin biosynthesis in G. zeae. Our results would provide important information for better understanding of naphthoquinone biosynthesis in other fdarnentous fungi as well as the aurofusarin biosynthesis in G. zeae.

• YAKHAK HOEJI
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• v.34 no.5
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• pp.311-322
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• 1990

This study primarily attempted to investigate the effects of methamphetamine on stereotyped behavior. Furthermore, an extensive experiment was conducted to examine the cortex methamphetamine concentration and levels of dopamine, serotonin, and their metabolites in striatum, septum and hypothalamus. Following treatment with 10 mg/kg methamphetamine, stereotyped behavior was observed in 10 minutes. Consequently female rats displayed more intense and longer lasting activity than the male. The concentration of cortex methamphetamine was even higher in female than male. The administration of methamphetamine increased the rate of dopamine turnover-i.e. lower dopamine, higher homovanillic acid in the striatum, septum. The highest rate was found in the striatum. Methamphetamine decreased the levels of serotonin, and its metabolite of 5-indoleacetic acid in the striatum, septum. An intensity in behavioral response was accompanied by an increase in dopamine turnover, a decrease in serotonergic transmission. The reduction of 3,4-dihydroxyphenylacetic acid-i.e. the metabolite of dopamine was due not to the inhibition of monoamine oxidase but to the induction of monoamine oxidase but to the induction of catechol-O-methyltransferase. The phenomenon of biogenic amines by methamphetamine concurred upon the concentration of methamphetamine in the brain. This process preceded stereotyped behavior. After single injection of 10 mg/kg methamphetamine, the levels of biogenic amines recovered within 6 hours.

• Radiation Oncology Journal
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• v.37 no.1
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• pp.1-12
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• 2019

Despite recent innovation in treatment techniques and subsequently improved outcomes, the majority of glioblastoma (GBL) have relapses, especially in locoregional areas. Local re-irradiation (re-RT) has been established as a feasible option for recurrent GBL of all ages with safety, tolerability, and effectiveness both in survival and quality of life regardless of fractionation schedule. To keep adverse effects under acceptable range, cumulative dose limit in equivalent dose at 2 Gy fractions by the linear-quadratic model at α/β = 2 for normal brain tissue (EQD2) with narrow margin should be observed and single/hypofractionated re-RT should be undertaken very carefully to recurrent tumor with large volume or adjacent to the brainstem. Promising outcome of re-operation (re-Op) plus re-RT (re-Op/RT) need to be validated and result from re-RT with temozolomide/bevacizumab (TMZ/BV) or new strategy is expected. Development of new-concept prognostic scoring or risk group is required to select patients properly and make use of predictive biomarkers such as O(6)-methylguanine-DNA methyltransferase (MGMT) promotor methylation that influence outcomes of re-RT, re-Op/RT, or re-RT with TMZ/BV.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.80.1-80
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• 2003

Several plant and microbial genes that could confer disease resistance in transgenic rice plants are being cloned and characterized. We are currently constructing transgenic rice lines that overexpress the gene products, such as a galactinol synthase, a defensin, and a bacterial ACC deaminase. Subtractive hybridization of a rice cDNA library constructed from the Xanthomonas oryzae-infected ice leaves resulted in isolation of many inducible cDNA clones including a elongation factor EF2, a oryzain alpha, a catalase, a aldehyde dehydrogenase, a S-adenosylmethionine synthetase, a caffeic acid O-methyltransferase, a glyceraldehyde-3-phosphate dehydrogenase, a light-regulated protein, nKY transcription factors, and a nucleotide diphosphate kinase. Some genes among those may be useful genetic sources for construction of disease resistant transgenic rice. Full lengths of the rice OsFIERG and a rice oryzain genomic clones were cloned, and serial deletion fragments of the promoter regions of these genes were fused with GUS reporter gene in pCAMBIA1201, respectively. Promoter activities of these constructs will be examined upon various stresses and Pathogen infections to obtain the pathogen specific inducible-promoter. This work was supported by a grant from BioGreen 21 Program, Rural Development Administration, Republic of Korea.

• Journal of Life Science
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• v.19 no.10
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• pp.1456-1462
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• 2009

D-chiro-Inositol, which is the isomer of myo-inositol, is a well known drug for the treatment of type II diabetes. The methylated form of D-chiro-inositol, D-pinitol and D-chiro-inositol are synthesized when the plants are exposed to the abiotic stresses such as drought, salinity and low temperature as osmoprotectants. In soybean, myo-inositol is converted to ononitol by O-methyltransferase, and ononitol is converted to D-pinitol by ononitol epimerase and finally converted to D-chiro-inositol by demethylase. However there have been some reports that in buckwheat, myo-inositol can be converted to D-chiro-inositol directly. This study was conducted to determine the changes of soluble cyclitols in buckwheat seedlings after exposure to salt and drought stresses by GC-FID. The results indicated that myo-inositol may be the precursor of D-chiro-inositol biosynthesis.

• Journal of Plant Biotechnology
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• v.35 no.4
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• pp.307-316
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• 2008

Transposon-mediated insertional mutagenesis is one of powerful strategy for assessing functions of genes in higher plants. In this report, we have selected highly susceptible and tolerance plant by screening about high salt (3% NaCl) and cold stresses ($4^{\circ}C$) from F2 seeds of 30,000 Ac/Ds insertional mutagenesis lines in rice (Oryza sativa L. cv. Dongjin). In order to identify the gene tagging, insertion of Ds element was analyzed by Southern blot and these results revealed that 19 lines were matched genotype of selected lines with phenotype from the first selected 212 lines, and 13 lines have one copy of Ds elements. The Franking Sequence Tags (FSTs) of selected mutant lines showed high similarities with the following known function genes: signal transduction and regulation of gene expression (transpoter, protease family protein and apical meristem family protein), osmotic stress response (heat shock protein, O-methyltransferase, glyceraldehyde-3-phosphate dehydrogenase and drought stress induce protein), vesicle trafficking (SYP 5 family protein) and senescence associated protein. The expression pattern of 19 genes were analyzed using RT-PCR under the abiotic stresses of 9 class; 250mM NaCl, osmotic, drought, 3% $H_2O_2$, $100{\mu}M$ ABA, $100{\mu}M$ IAA, 0.1 ppm 2,4-D, $4^{\circ}C$ cold and $38^{\circ}C$ high temperature. Isolated knock-out genes showed the positive response about 250 mM NaCl, drought, $H_2O_2$, PEG, IAA, 2,4-D, ABA treatment and low ($4^{\circ}C$) and high temperature ($38^{\circ}C$). The results from this study indicate that function of selected knock-out genes could be useful in improving of tolerance to abiotic stresses as an important transcriptional activators in rice.