• The Plant Pathology Journal
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• v.19 no.1
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• pp.34-42
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• 2003

The ascomycete Magnaporthe grisea is a pathogen of rice blast and is known to form specialized infection structures called appressoria for successful infection into host cells. To understand the molecular mechanism underlying infection process, appressorium-related genes were identified through global approaches including EST sequencing, differential hybridization, and sup-pression subtractive hybridization. EST database was generated on >2,000 cDNA clones randomly selected from appressorium stage cDNA library. Large number of ESTs showed homology to known proteins possibly involved in infection-related cellular development (attachment, germination, appressorium formation, and colonization) of rice blast fungus. The 1051 ESTs showing significant homology to known genes were assigned to 11 functional categories. Differential hybridization and suppression subtractive hybridization were applied to identify genes showing an appressorium stage specific expression pattern. A number of genes were selected as up-regulated during appressorium formation compared with the vegetative growing stage. Clones from various cDNA libraries constructed in different developmental stages were arrayed on slide glass for further expression profiling study. functional characterization of genes identified from these global approaches may lead to a better understand-ing of the infection process of this devastating plant disease, and the development of novel ways to protect host plant.

• Molecules and Cells
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• v.41 no.7
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• pp.665-675
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• 2018

Rice is a facultative short-day (SD) plant in which flowering is induced under SD conditions or by other environmental factors and internal genetic programs. Overexpression of Histone Deacetylase 701 (HDT701) accelerates flowering in hybrid rice. In this study, mutants defective in HDT701 flowered late under both SD and long-day conditions. Expression levels of florigens Heading date 3a (Hd3a) and Rice Flowering Locus T1 (RFT1), and their immediate upstream floral activator Early heading date 1 (Ehd1), were significantly decreased in the hdt701 mutants, indicating that HDT701 functions upstream of Ehd1 in controlling flowering time. Transcript levels of OsINDETERMINATE SPIKELET 1 (OsIDS1), an upstream repressor of Ehd1, were significantly increased in the mutants while those of OsGI and Hd1 were reduced. Chromatin-immunoprecipitation assays revealed that HDT701 directly binds to the promoter region of OsIDS1. These results suggest that HDT701 induces flowering by suppressing OsIDS1.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.11
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• pp.1674-1680
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• 2014

The aim of this study was to investigate the protective effects of methanolic extracts of cooked mixed grain rice samples, including grain rice (sorghum, black bean, proso millet, and Job's tears) mixed with fermented brown rice (GR), GR added with 0.5% water extract of Sanghwang mushroom (GRS) or 0.1% curry (GRK), and traditional five grain mixed rice (TMR, Ohgokbap), on $H_2O_2$-induced oxidative injury in LLC-PK1 pig renal epithelial cells. White rice (WR) was used as a positive control. Cells were first exposed to $H_2O_2$ ($250{\mu}M$) for 4 hr, followed by treatment with $100{\mu}g/mL$ of different GR extracts for 24 hr. $H_2O_2$ significantly induced cell damage (P<0.05). Cellular levels of reactive oxygen species (ROS), lipid peroxidation, and antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-px), were measured. In addition, mRNA levels of antioxidant enzymes were determined by RT-PCR assay. Mixed grain rice, particularly GRS and GRK, were able to reduce cellular levels of ROS, decrease lipid peroxidation, and also increase mRNA expression of antioxidant enzymes compared to other samples. These results suggest that mixed grain rice, specifically GRS and GRK, have strong protective effects against $H_2O_2$-induced oxidative injury in LLC-PK1 cells through inhibition of lipid peroxidation, reduction of ROS levels, and elevation of antioxidant enzyme activities.

• The Korean Journal of Food And Nutrition
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• v.13 no.5
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• pp.411-418
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• 2000

The purpose of this study was to investigate effects of chestnut inner skin tea, brown rice-green tea and Cassia lora tea on the activation of physiological functions (regional cerebral blood flow, mean arterial blood pressure, proliferation of immunocytes in vitro and in vitro, suppression of cancer cell proliferation) in mouse and rat. We used 8 weeks-old balb/c male mice, 300g ICR rats and L1210 cell lines. Regional cerebral blood flow(rCBF) and mean arterial blood pressure(BP) were measured using Leser-Doppler Flowmetry(LDF) and the proliferation of cells was measured using a colorimetric tetrazolium assay(MTT assay). The experimental results are as follows : 1. rCBF was increased by Cassia tora tea, but decreased by chestnut inner skin tea in rats. 2. BP was increased by brown rice-green tea in rats. 3. Proliferation of mouse thymocytes and splenocytes were significantly increased by chestnut inner skin tea in vitro. 4. Proliferation of mouse thymocytes was decreased by Cassia tora tea and brown rice-green tea in vitro. 5. Proliferation of mouse thymocytes was decreased by Cassia tora tea and brown rice-green tea in L1210 transplanted mice. 6. Proliferation of splenocytes was accelerated by chestnut inner skin tea in L1210 transplanted mice. 7. Proliferation of L1210 cells was inhibited by chestnut inner skin tea and Cassia tora tea in L1210 transplanted mice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.599-604
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• 2005

The aim of this study was to develop the new processing method for ginseng. To investigate the efficacy of the new product (the traditional rice wine steamed-red ginseng: RWS-RGS), antioxidant and anticancer effects of RWS-RGS were examined. The DPPH radical scavenging effect of RWS-RGS extracted with ethanol was increased in dose-dependent manner Especially, A3 ($3^{rd}$ traditional rice wine steamed-red ginsengs) exhibited effective DPPH radical scavenging activity. Nitrite scavenging effect of white ginseng (W.G), red ginseng (R.G) and RWS-RGS ($A1\~A9:\;1^{st}$ traditional rice wine steamed-red $ginseng\~9^{th}$ traditional rice wine steamed-red ginseng) were $25.9{\pm}4.4\%,\;12.9{\pm}1.1\%\;and\;26.2{\pm}0.1\~56.1{\pm}0.6\%$ at pH 1.2, respectively. The antitumor effects of W.G, R.G and RWS-RGS (A9) were examined in Hep3B cancer cells. Their growth inhibition against Hep3B cancer cells showed $19.6{\pm}4.5\%,\;54.5{\pm}6.1\%,\;96.3{\pm}2.4\%$ at 5,000 ppm, respectively. These result suggest that the traditional rice wine steamed ginseng will be useful product with antioxidant and antitumor effect.

• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.11-11
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• 1999

;It has been reported that suspension-cultured rice cells grown on mixed carbon sources of glucose (GIc) and acetate exhibited diauxic growth in which acetate was the preferred carbon source (Lee and Lee, 1996). Carrot (Daucus carota L.) suspension cells, showing a diauxic growth very similar to that of rice cells, were used to delineate the mechanisms underlying this preferential use of acetate over GIc. Uptakes of both GIc and 3-0-methylglucose (3-0MG), a non-metabolizable GIc analogue, were similarly inhibited when acetate or butylate, weak acids which are capable of transporting protons into the cytosol, were present in the uptake assay mixture containing cells harvested during the GIc-utilizing second growth phase. Inhibition of GIc uptake by these weak acids was similar when equivalent experiments were carried out with isolated plasma membranes. It was further shown that Glc uptake, which requires a proper proton gradient across the plasma membranes, was inhibited during the first growth phase by acetate-mediated alkalization of growth medium and/or simultaneous acidification of cytosol. This study strongly suggests that Glc utilization in plant cells is inhibited by co-presenting carbon source(s) which can alter the proton gradient across the plasma membrane. We further examined diauxic growth in culture containing GIc and malate. Unlike the case in the culture with GIc and acetate, carrot cells used GIc first. Malate was utilized only after Glc is depleted from medium. These results indicate that GIc can be a preferred or less-preferred carbon source depending on the competing carbon source. It was noted that malate was not directly taken up by cells. Instead it was converted extracellularly into fumarate which was subsequently transported into cells. During the malate-growth phase malate uptake was negligible, and fumarate uptake was active and pH-sensitive. It was shown that fumarase released into medium was responsible for the extracellular conversion of malate into fumarate. An immunoblot experiments showed that fumarase antibody raised against Arabidopsis fumarase provided positive signals only in medium in malate culture, not in fumarate or GIc cultures. This study demonstrates the first example in that fumarase, a mitochondria marker enzyme, can be present in places other than mitochondria.ndria.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.203-204
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• 2005

• Journal of Life Science
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• v.18 no.10
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• pp.1390-1394
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• 2008

Previously, we found that the transgenic rice plants over-expressing the Arabidopsis $H^+/Ca^{2+}$ antiporter CAX 1 (accession no. U57411) gene accumulated 2.7 to 7.5-fold more calcium in the T3 rice grains as compared to those of control. To examine physiological safety of the $T_3$ rice grains, the effect of the $T_3$ brown rice on change in levels of body weight and white blood cells was compared with that of the control Ilpum brown rice by feeding trial in mice. During the feeding trial for one month, there was no significant difference between two mice groups, which were fed by the $T_3$ brown rice or Ilpum brown rice. There were no detectable differences in their effects on immune functions including plaque-forming unit, peritoneal macrophage number, and NK-cell activity. In addition, biochemical analysis of the blood failed to exhibit any difference between two mice groups. Together, these results suggested that the $T_3$ brown rice, which was produced from a genetically modified organism (GMO), might be safe and possess a potential to be applicable as calcium-fortified feed or food. Long-term safety of the $T_3$ brown rice, however, remains to be elucidated.

• Korean Journal of Weed Science
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• v.14 no.2
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• pp.144-155
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• 1994

Scanning electron micrography and Transmission electron micrography studies were performed on the surfaces of stem(coleoptiles) of rice and barnyardgrass under various cropping patterns at 5 days after seeding or transplanting. Stem surfaces of rice under dry condition possessed rodlet-like epicuticular waxes, trichomes, stomata and cork cell layer in both broadcast and drilled rice while barnyardgrass had only thread-like epicuticular waxes, but trichomes, stomata and cork cell layers were not found. However, rice under water condition has no rodlet-like waxes, stomata and cork cells, and barnyardgrass was similar to that under dry condition. On the other hand, those on stems of 8-day and 25-day transplanted rice were well arranged and developed compared with those of direct seeded rice. Electron micrography showed significant difference in thickness of outer epidermal cell walls of rice and barnyardgrass under dry, water and transplanting condition. Thickness of outer epidermal cell was greater in transplanted rice, dry direct seeded rice, water-direct seeded rice and barnyardgrass in descending order.

• Korean Journal of Food Science and Technology
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• v.41 no.5
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• pp.572-577
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• 2009

The effects of cereal (rice, brown rice, barley, glutinous rice) ethanol extracts on the proliferation, nitric oxide (NO) production, and level of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) in B and T lymphocytes, isolated from human blood cells of sasang constitution, were examined in vitro. The rice, brown rice, and glutinous rice ethanol extract, which are known as suitable for eumin (taeumin and soeumin) constitutions, showed the highest activities for proliferation, NO production, and TNF-${\alpha}$ concentration, respectively. However, the barley ethanol extract, which is known tobe suitable for yangin (taeyangin and soyangin) constitutions, showed the highest overall activities for proliferation, NO production, and TNF-${\alpha}$ concentration. The different immunological activities of the cereal extracts in sasang constitution lymphocytes might be due to their individual components. Thus, determination of components from the cereal extracts suitable for sasang constitution could be useful in new food developments.