• KSBB Journal
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• v.20 no.1 s.90
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• pp.21-25
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• 2005

Paraquat, a widely used herbicide, has been suggested as a potential risk factor for Parkinson's disease. Heme oxygenase-1(HO-1), a marker for oxidative stress and endoplasmic reticulum(ER) stress, is known to catalyze heme to biliverdin, carbon monoxide and free iron in response to various stimuli. Here we show that paraquat activates HO-1 expression in a time-and dose-dependent manner in substantia nigra(SN) dopaminergic neuronal cells. Activation of Ho-1 by paraquat was regulated primarily at the level of gene transcription. Deletion analysis of the promoter and the 5' distal enhancers, E1 and E2, of the HO-1 gene revealed that the E2 enhancer is a potent inducer of the paraquat-dependent Ho-1 gene expression in dopamninergic neuronal cells. Mutational analysis of the E2 enhacer further demonstrated that the transcription factor activator protein-1(AP-1) plays an important role in mediating paraquat-induced HO-1 gene transcription. Moreover, using specific inhibitors of the mitogen-activated protein kinases(MAPKs), we investigated the role of paraquat and MAPKs for HO-1 gene regulation in dopaminergic cells. The c-Jun N-terminal kinase(JNK) inhibitor SP600125 significantly suppressed the expression of HO-1 by paraquat. All these results demonstrate that induction of HO-1 by paraquat requies the activation of the AP-1 and JNK pathway.

• Korean Journal of Weed Science
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• v.31 no.1
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• pp.112-117
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• 2011

A series of experiments was conducted to investigate the herbicidal activity of natural compound chrysophanic acid under the greenhouse condition in 16 weed species. Chrysophanic acid showed non-selective herbicidal activity. While chrysophanic acid exhibited severe injury by foliar treatment, little or no injury was found by the soil treatment. Among the tested weeds, the most effective activity was found in grass and broad leaf weeds, a lower significant difference in herbicidal activity was found in sedge. At early post-emergence, weeds appeared to be very susceptible to chrysophanic acid with $2,000{\mu}g\;mL^{-1}$. The higher the natural compound concentrations, the lower weed growth. At middle post-emergence, weeds appeared to be very effective to chrysophanic acid with $30,000{\mu}g\;mL^{-1}$.

• Asian Journal of Turfgrass Science
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• v.20 no.2
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• pp.157-165
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• 2006

This study was initiated to investigate herbicidal selectivity margin with annual bluegrass and bentgrass according to growth stages through herbicidal spectrum of bispyribac-sodium and therefore to examine application possibility to prevent annual bluegrass selectively. The herbicidal efncacy by pre-emergence application was generally low. But a high herbicidal efficacy was observed over 90% for Shehpherd's purse. Foliar treatment resulted in a higher herbicidal efficacy in all tested plants except dallisgrass, lovegrass, curled dock and bentgrass as compared with pre-emergence application. We found bispyribac-sodium could be used as a selective weeding chemical between annual bluegrass and bentgrass. In regard to dose-responses to the growth stage, annual bluegrass was more susceptible to bispyribac-sodium than bentgrass for the same dosage. Particularly, bispyribac-sodium application in inflorescence emergence stage showed a greater herbicidal selectivity margin of 6.8 times with annual bluegrass over creeping bentgrass after 28 days from the application. These data demonstrated that annual bluegrass was more sensitive to bispyribac-sodium over creeping bentgrass.

• Journal of Life Science
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• v.31 no.2
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• pp.109-114
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• 2021

Oryzalin is a dinitroaniline herbicide that has been known to disrupt microtubules. Microtubules and microfilaments are components of cytoskeletons that are implicated in plant cell growth, which requires the synthesis of cellulose when cell walls elongate. In addition, microtubules are also involved in the sedimentation of statoliths, which regulate the perception of gravity in the columella cells of root tips. In this study, we investigated the effect of oryzalin on the growth and gravitropic response of Arabidopsis roots. The role of ethylene in oryzalin's effect was also examined using these roots. Treatment of oryzalin at a concentration of 10-4 M completely inhibited the roots' growth and gravitropic response. At a concentration of 10-6 M oryzalin, root growth was inhibited by 47% at 8 hr when compared to control. Gravitropic response was inhibited by about 38% compared to control in roots treated with 10-6 M oryzalin for 4 hr. To understand the role of oryzalin in the regulation of root growth and gravitropic response, we measured ethylene production in root segments treated with oryzalin. It was found that the addition of oryzalin stimulated ethylene production through the activation of ACC oxidase and ACC synthase genes, which are key components in the synthesis of ethylene. From these findings, it can be inferred that oryzalin inhibits the growth and gravitropic response of Arabidopsis roots by stimulating ethylene production. The increased ethylene alters the arrangement of the microtubules, which eventually interferes with the growth of the cell wall.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.112-112
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• 2022

외래잡초인 애기수영(Rumex acetosella)는 생태계 교란종으로 생물다양성을 감소시키고, 우리나라 목초지에 우점하고 있어 큰 문제를 야기한다. 애기수영의 경우, 살초효과 및 제초활성물질인 chrysophanic acid와 catechd이 밝혀져 있지만, 톨페스큐(Festuca arundinacea)에 대한 살초 효과 연구는 미비하다. 이에 본 연구는 톨페스큐 종자에 대해 애기수영 MeOH 추출물을 처리한 Seed bioassay를 진행해 IC₅₀ 값을 구하고, 톨페스큐에 애기수영 MeOH 추출물을 경엽처리를 진행한 후 생육조사를 진행했다. Seed bioassay의 경우, petri dish 위에 톨페스큐 종자 20개가 치상하고, 애기수영 지상부 추출물과 지하부 추출물을 각각 20,000 mg L^-1, 10,000 mg L^-1, 5,000 mg L^-1, 2,500 mg L^-1 농도로 serial dilution 하여 1mL씩 분주한 뒤, 일주일 뒤에 발아한 종자에 대해 생체중을 조사하고 Prizm 프로그램을 이용해 IC₅₀을 구하였다. 경엽처리의 경우, 톨페스큐 종자 파종4주 뒤에 IC₅₀값이 더 낮았던 지상부 추출물을 100,000 mg L^-1, 50,000 mg L^-1, 25,000 mg L^-1, 12,500 mg L^-1, 6,250 mg L^-1 농도로 serial dilution 한 뒤 5mL씩 일주일 간격으로 3회 경엽처리를 진행하였고, 마지막 처리 일주일 뒤 초장, 근장, 생체중, 건물중을 조사하였다. Seed bioassay 결과, 애기수영 지하부 추출물에 대한 톨페스큐의 IC₅₀값은 3274가 나왔고, 애기수영 지상부 추출물에 대한 톨페스큐의 IC₅₀값은 2728가 나왔다. Seed bioassay 결과를 바탕으로 효과적 이 었던 지상부 추출물을 이용해 톨페스큐 경엽처리를 진행하였다. 애기수영 지상부 추출물 경엽처리 결과, 톨페스큐 초장과 생체중이 추출물 처리량이 높아짐에 따라 낮아졌으며, 100,000 mg L^-1 처리구는 Control과 비교해 유의적으로 감소하였고, 처리량이 높아짐에 따라 근장이 감소했지만, 유의적인 차이는 없었다. 그리고 건물중은 100,000 mg L^-1 처리구가 Control, 12,500 mg L^-1, 6,250 mg L^-1 처리구와 비교해 유의적으로 낮았다.

• Korean Journal of Weed Science
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• v.31 no.2
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• pp.134-145
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• 2011

The objectives of this study were to investigate fitness difference in growth and rice yield in herbicide-transgenic rice overexpressing Myxococcus xanthus and Arabidopsis thaliana protoporphyrinogen oxidase (Protox) genes and non-transgenic rice. We also aimed to determine whether these fitness differences are related to ALA synthesizing capacity, accumulation of terapyrroles, reactive oxygen species, lipid peroxidation, and antioxidative enzymes at different growth stages of rice. Plant height of the transgenic rice overexpressing M. xanthus (MX) and A. thaliana (AP37) Protox genes at 43, 50, and 65 days after transplanting (DAT) was significantly lower than that of WT. Number of tiller of PX as well as MX and AP37 at 50 and 65 DAT was significantly lower than that of WT. At harvest time, culm length and yield of MX, PX and AP37 and rice straw weight of MX and AP37 were significantly low compared with WT. The reduction of yield in MX, PX, and AP37 was caused by spikelets per panicle and 1000 grain weight, ripened grain, spikelets per panicle, 1000 grain weight, and ripened grain, respectively. On the other hand, 135 the reduction of yield in MX, PX, and AP37 was also observed in another yearly variation experiment. The reduction of rice growth in MX, PX, and AP37 was observed in seedling stage as well as growth duration in field. There were no differences in tetrapyrrole intermediate Proto IX, Mg-Proto IX and Mg-Proto IX monomethyl ester, reactive oxygen species ($H_2O_2$ and ${O_2}^-$), MDA, antioxidative enzymes (SOD, CAT, POX, APX, and GR) and chlorophyll between transgenic lines and wild type, indicating that accumulated tetrapyrrole intermediate and other parameters were not related to growth reduction in transgenic rice. However, ALA synthesizing capacity in MX, PX, and AP37 at one day after exposure to light and 52 DAT was significantly lower than that of WT. Further study is required to elucidate the mechanisms underlying the growth and yield difference between transgenic and WT lines.

• The Korean Journal of Pesticide Science
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• v.4 no.4
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• pp.19-25
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• 2000

The leaching behaviour of quinclorac was elucidated using soil columns. On top of each glass column packed with a rice paddy soil up to the 30 cm height were applied three different treatments of [$^{14}C$]quinclorac: quincloiac only (T-1), quinclorac adsorbed onto active carbon (T-2), and quinclorac adsorbed onto a mixture of active carbon and $Ca(OH)_{2}$ (T-3). Half of the columns were planted with rice plants for 17 weeks and half of them unplanted for comparison. Average amounts of $^{14}C$-activity percolated from tile soil columns without rice plants in T-1, T-2, and T-3 were 81.1%, 27.8% and 48.0%, respectively, of tile originally applied $^{14}C$, whereas those with rice plants grown were 36.8%, 9.6% and 11.0%, respectively, indicating that the leaching of [$^{14}C$]quinclorac was significantly affected by vegetation and by treatment with the adsorbents. The bioavailability of the herbicide to rice plants in T-1, T-2, and T-3 were 13.6%, 11.0% and 13.9%, respectively. The residue levels of quinclorac in the edible part of rice grains would be far less than the maximum residue limit (MRL, 0.5 ppm). After the leaching, the amounts of $^{14}C$ remaining in soil in with rice planting T-1, T-2, and T-3 were 36.3%, 73.7%, and 61.8%, whereas those without rice planting were 19.7%, 71.1%, and 52.3%, respectively. The balance sheets indicate that [$^{14}C$]quinclorac translocated to rice shoots would be lost by volatilization and/or in other ways in T-1 and T-3. The $^{14}C$-activity partitioned into the aqueous phase of the leachates collected from all treatments was less than 7% of the total, but it increased gradually with time in the case of rice growing, suggesting tile formation of some polar degradation products.

• Journal of Plant Biotechnology
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• v.36 no.1
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• pp.30-37
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• 2009

Tissue-type plasminogen activator (t-PA) is a thrombolytic agent important in fibirn clot lysis. T-PA causes fibirn-specific plasminogen activation. Six binary vectors harboring t-PA and its derivative genes were cloned and expressed in transgenic alfalfa plants. The insertion of the t-PA and its derivative genes in genomic DNA of alfalfa plants was confirmed by PCR. The presence of the t-PA and its derivative transcripts in total RNAs of the transgenic alfalfa leaves was verified by RT-PCR. ELISA experiments demonstrated that the highest level of recombinant t-PA expression was $75.1{\mu}g$/ total soluble protein (mg) in alfalfa plants. The amount of recombinant t-PA and its derivative proteins in transgenic plants was estimated to range from 9.7 to $39.5{\mu}g$/ total soluble proteins (mg). Western blot analysis of the transformed alfalfa leaves revealed bands of approximately 68-kDa recombinant t-PA and its derivative proteins. The fibrinolysis of recombinant t-PA and its derivative proteins was confirmed by a fibrin plate assay (range from 3.2 to 8.1 cm). The results presented provide information for the development of an additional production of recombinant human proteins having pharmaceutical applications using transgenic plants.

• Horticultural Science & Technology
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• v.34 no.1
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• pp.112-121
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• 2016

Development of genetically-modified (GM) crops enables the introduction of new traits to the plant to confer characteristics such as disease resistance, herbicide resistance and human health-promoting bioactivity. Successful commercialization of newly developed GM crops requires stable inheritance of integrated T-DNA and newly introduced traits through the multiple generations. This study was carried out to confirm the stable inheritance of the integrated T-DNA in $T_1$ and $T_2$ transgenic Chinese cabbage (Brassica rapa ssp. pekinensis) that was genetically modified to increase concentrations of phenylethylisothiocyanate (PEITC), which is a potential anti-carcinogenic phytochemical. For this purpose, the IGA 1-3 ($T_1$ generation) and IGA 1-3-5 ($T_2$ generation) lines were selected by PCR and a IGA 1-3 transgenic plant ($T_1$ generation) was analyzed to confirm the T-DNA insertion site in the Chinese cabbage genome by VA-TAIL PCR. The results of this study showed that the introduced T-DNA in IGA 1 line was stably inherited to the next generations without any variations in terms of the structure of the transgenes, and this line also showed the expected transgene function that resulted in increased concentration of PEITC through the multiple generations. Finally, we confirmed the increased QR activity in IGA 1 $T_1$ and $T_2$ transgenic lines, which indicates an enhanced potential anti-carcinogenic bioactivity and its stable inheritance in IGA1 $T_1$ and $T_2$ transgenic lines.

• Korean Journal of Plant Tissue Culture
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• v.28 no.5
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• pp.289-296
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• 2001

The main objective of this topic is to establish strategies and to plan biotechnology researches which are related to the agricultural improvements especially focusing on the crop breeding in Korea. From 1960's to 1980's government policy had been emphasized to develope high yielding cultivars for the self sufficient supply of the staple food crops. As a result, considerable increase of rice production has been made with accumulating technology and man's powers. Recently genetically modified crops harboring useful characteristics have been developed using biotechnology and released in the developed countries. National research institutes and private companies have been developed biotechnology researches to establish competitive capabilities, however they have not been successfully used in commercialization. Therefore it is necessary to promote the practical. application by connecting molecular technology with conventional breeding. Proposed research projects are; (1) basic researches including plant genome studies, (2) developing new cultivars through gene transformation, (3) screening and producing antioxidants, secondary metabolite substances and edible vaccines. To set a government policy, both domestic and international research trends were reviewed and possibility of success based on the economic view point were discussed. The intellectual property and preservation of environment play a key role to decide the research priority. It is also necessary for us to make one step system for the distribution of research resources such as microorganisms, genes cloned, plant seeds and research informations for promoting research activities.