• Journal of Applied Biological Chemistry
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• 제64권4호
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• pp.369-374
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• 2021

느타리버섯의 갈반병은 Pseudomonas tolaasii에 의해 생성된 톨라신 및 이의 유사 펩티드 독소에 의해 발생한다. 톨라신 펩티드들은 세포막에 pore를 형성하고 버섯의 자실체 구조를 파괴한다. 적혈구가 파괴되는 용혈은 톨라신의 세포독성에 의해 일어난다. 톨라신의 용혈활성은 Zn²⁺ 및 Ni²⁺과 같은 금속 이온에 의해 저해된다. 가돌리니움 이온을 첨가하였을 때, 톨라신에 의한 용혈작용에서 1 mM 이하의 농도에서는 용혈작용이 증가하고 그 이상의 농도에서는 저해되는 이중 효과가 나타났다. 가돌리니움 이온에 의한 톨라신 활성저해 기작은 다른 양이온들에 의한 저해기작과 다른 것으로 보인다. 가돌리니움 이온은 음전하를 갖는 막지질들에 결합하여 지질막의 측압을 변화시키는 것으로 보고되어, 톨라신 이온통로의 여닫힘에 직접 작용하기 보다는 막 구조의 단단함을 증가시켜 막에 대한 톨라신 이온통로의 안정성을 감소시키는 것으로 보인다.

• Journal of Microbiology and Biotechnology
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• 제31권4호
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• pp.529-539
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• 2021

The beet armyworm, Spodoptera exigua, is a serious insect pest infesting various vegetable crops. Two infectious insect viruses, baculovirus and iflavirus, are known to induce epizootics in S. exigua populations. Indeed, some laboratory colonies have appeared to be covertly infected by these viruses. Diagnostic PCR tests detected two different viruses: Spodoptera exigua multiple nucleopolyhedrosis virus (SeMNPV) and iflaviruses (SeIfV1 and SeIfV2). Viral extract from dead larvae of S. exigua could infect Sf9 cells and produce occlusion bodies (OBs). Feeding OBs to asymptomatic larvae of S. exigua caused significant viral disease. Interestingly, both SeIfV1 and SeIfV2 increased their titers at late larval stages. Sterilization of laid eggs with 1% sodium hypochloride significantly reduced SeMNPV titers and increased larval survival rate. Double-stranded RNA (dsRNA) specific to SeIfV1 or SeIfV2 significantly reduced viral titers and increased larval survival rate. To continuously feed dsRNA, a recombinant Escherichia coli HT115 expressing SeIfV1-dsRNA was constructed with an L4440 expression vector. Adding this recombinant E. coli to the artificial diet significantly reduced the SeIfV1 titer and increased larval survival. These results indicate that laboratory colony collapse of S. exigua is induced by multiple viral infections. In addition, either suppression of SeMNPV or SeIfV infection significantly increased larval survival, suggesting a cooperative pathogenicity between baculovirus and iflavirus against S. exigua.

• Anatomy and Cell Biology
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• 제51권4호
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• pp.292-298
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• 2018

Experimental autoimmune encephalomyelitis (EAE) is a T-cell-mediated autoimmune central nervous system disease characterized by inflammation with oxidative stress. The aim of this study was to evaluate an anti-inflammatory effect of Ishige okamurae on EAE-induced paralysis in rats. An ethanolic extract of I. okamurae significantly delayed the first onset and reduced the duration and severity of hind-limb paralysis. The neuropathological and immunohistochemical findings in the spinal cord were in agreement with these clinical results. T-cell proliferation assay revealed that the ethyl-acetate fraction of I. okamurae suppressed the proliferation of myelin basic protein reactive T cells from EAE affected rats. Flow cytometric analysis showed $TCR{\alpha}{\beta}^+$ T cells was significantly reduced in the spleen of EAE rats with I. okamurae treatment with concurrent decrease of inflammatory mediators including tumor necrosis $factor-{\alpha}$ and cyclooxygenase-2. Collectively, it is postulated that I. okamurae ameliorates EAE paralysis with suppression of T-cell proliferation as well as decrease of pro-inflammatory mediators as far as rat EAE is concerned.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 춘계학술대회
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• pp.120-120
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• 2019

Allergic inflammatory disease has been increased by abnormal lifestyle and food habits. Especially, prevalence of atopic dermatitis (AD) has been elevated and treatment of AD has not been unclear. Red sweet pepper (RSP), named as Capsicum annuum L, has been known as having pharmacological effects such as antioxidant, detoxification and antibacterial effects. However, the beneficial effect of ethanolic extract of RSP on AD has not been partly examined yet. Therefore, the aim of this study was to investigate anti-inflammatory effects of RSP on AD in vitro and in vivo models. The treatment of RSP inhibited the secretion of inflammatory cytokine such as interleukin (IL)-6 and IL-8 in tumor necrosis factor (TNF)-${\alpha}$ and interferon (IFN)-${\gamma}$-stimulated human keratinocyte (HaCaT cell). Also, RSP extract regulated 2,4-dinitroflorobenzene (DNFB)-induced AD-like skin lesions in BALB/c mice. Oral administration of RSP ameliorated DNFB-induced AD-like symptoms. In presented results indicated that RSP inhibited inflammatory cytokines in HaCaT cell and ameliorated AD-like skin lesion through suppression of symptom of DNFB-induced skin inflammation. Thus, RSP might be a potential therapeutic agent for AD.

• Journal of Microbiology and Biotechnology
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• 제29권1호
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• pp.66-78
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• 2019

In this study, strain KNU17Pc1 was tested for its antifungal activity against Rhizoctonia solani AG-1(IA), which causes banded leaf and sheath blight (BLSB) of maize. KNU17Pc1 was tested further for its broad-spectrum antifungal activity and in vitro plant growth promoting (PGP) traits. In addition, the in vivo effects of KNU17Pc1 on reduction of BLSB severity and seedling growth promotion of two maize cultivars under greenhouse conditions were investigated. On the basis of multilocus sequence analysis (MLSA), KNU17Pc1 was confirmed as P. chlororaphis subsp. aurantiaca. The study revealed that KNU17Pc1 had strong in vitro antifungal activity and was effective toward all in vitro PGP traits except phosphate solubilization. In this study, for the first time, a strain of P. chlororaphis against Colletotrichum dematium, Colletotrichum gloeosporioides, Fusarium oxysporum f.sp. melonis, Fusarium subglutinans and Stemphylium lycopersici has been reported. Further biochemical studies showed that KNU17Pc1 was able to produce both types of phenazine derivatives, PCA and 2-OH-PCA. In addition, solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) analysis identified 13 volatile organic compounds (VOCs) in the TSB culture of KNU17Pc1, 1-undecene being the most abundant volatile. Moreover, for the first time, Octamethylcyclotetrasiloxan (D4), dimethyl disulfide, 2-methyl-1,3-butadiene and 1-undecene were detected in P. chlororaphis. Furthermore, this study reported for the first time the effectiveness of P. chlororaphis to control BLSB of maize. Hence, further studies are necessary to test the effectiveness of KNU17Pc1 under different environmental conditions so that it can be exploited further for biocontrol and plant growth promotion.

• The Plant Pathology Journal
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• 제35권3호
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• pp.257-273
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• 2019

Tomato (Solanum lycopersicum) is one of the most widely grown and economically important vegetable crops in the world. Tomato chlorosis virus (ToCV) is one of the recently emerged viruses of tomato distributed worldwide. ToCV-tomato interaction was investigated at the molecular level for determining changes in the expression of tomato genes in response to ToCV infection in this study. A cDNA library enriched with genes induced in response to ToCV infection were constructed and 240 cDNAs were sequenced from this library. The macroarray analysis of 108 cDNAs revealed that the expression of 92 non-redundant tomato genes was induced by 1.5-fold or greater in response to ToCV infection. The majority of ToCV-induced genes identified in this study were associated with a variety of cellular functions including transcription, defense and defense signaling, metabolism, energy, transport facilitation, protein synthesis and fate and cellular biogenesis. Twenty ToCV-induced genes from different functional groups were selected and induction of 19 of these genes in response to ToCV infection was validated by RT-qPCR assay. Finally, the expression of 6 selected genes was analyzed in different stages of ToCV infection from 0 to 45 dpi. While the expression of three of these genes was only induced by ToCV infection, others were induced both by ToCV infection and wounding. The result showed that ToCV induced the basic defense response and activated the defense signaling in tomato plants at different stages of the infection. Functions of these defense related genes and their potential roles in disease development and resistance to ToCV are also discussed.

• 한방안이비인후피부과학회지
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• 제34권3호
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• pp.70-79
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• 2021

Objectives : The purpose of this study is to investigate the possibility of using herbal medicine for the management of psoriasis focusing on lipid metabolism. Methods : We reviewed studies about pathophysiology, and medical treatment of psoriasis, the relationship between psoriasis and metabolic syndrome and lipid metabolism, and herbal medicine on Pubmed and Google scholar. Results : Psoriasis is a chronic multi-organ inflammatory disease not limited to skin, and steroids, immuno-suppressants, and biological agents are used. It is known that psoriasis and metabolic syndrome act as mutual risk factors, and lipid metabolism are involved in psoriasis. The effects of various single herbal preparations and complex herbal extract, decoction on improving lipid metabolism have been consistently reported, and there was an improvement of psoriatic skin lesions and improvement of blood lipid levels through herbal medicine. Conclusions : Herbal medicine research in psoriasis has focused on the anti-inflammatory effect and the suppression effect of certain immune mediators. However, considering that psoriasis is affected by lipid metabolism and side effects of Western medicines, the use of herbal medicines for the purpose of controlling lipid metabolism in psoriasis is useful in aspects of reducing side effects of concurrent Western medicine, improving the severity of psoriasis, and managing metabolic risk factors.

• Biomolecules & Therapeutics
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• 제29권2호
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• pp.127-134
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• 2021

Neuroinflammation―a common pathological feature of neurodegenerative disorders such as Alzheimer's disease―is mediated by microglial activation. Thus, inhibiting microglial activation is vital for treating various neurological disorders. 7,3',4'-Trihydroxyisoflavone (THIF)―a secondary metabolite of the soybean compound daidzein―possesses antioxidant and anticancer properties. However, the effects of 7,3',4'-THIF on microglial activation have not been explored. In this study, antineuroinflammatory effects of 7,3',4'-THIF in lipopolysaccharide (LPS)-stimulated BV2 microglial cells were examined. 7,3',4'-THIF significantly suppressed the production of the proinflammatory mediators nitric oxide (NO), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) as well as of the proinflammatory cytokine interleukin-6 (IL-6) in LPS-stimulated BV2 microglial cells. Moreover, 7,3',4'-THIF markedly inhibited reactive oxygen species (ROS) generation. Western blotting revealed that 7,3',4'-THIF diminished LPS-induced phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), glycogen synthase kinase-3β (GSK-3β), and nuclear factor kappa B (NF-κB). Overall, 7,3',4'-THIF exerts antineuroinflammatory effects against LPS-induced microglial activation by suppressing mitogen-activated protein kinase (MAPK) and NF-κB signaling, ultimately reducing proinflammatory responses. Therefore, these antineuroinflammatory effects of 7,3',4'-THIF suggest its potential as a therapeutic agent for neurodegenerative disorders.

• Journal of Ginseng Research
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• 제45권4호
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• pp.490-497
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• 2021

Background and objective: Synthetic ginsenoside compounds G-Rp (1,3, and 4) and natural ginsenosides in Panax ginseng 20(S)-Rg3, Rg6, F4 and Ro have inhibitory actions on human platelets. However, the inhibitory mechanism of ginsenoside Rk1 (G-Rk1) is still unclear thus, we initiated investigation of the anti-platelet mechanism by G-Rk1 from Panax ginseng. Methodology: Our study focused to investigate the action of G-Rk1 on agonist-stimulated human platelet aggregation, inhibition of platelet signaling molecules such as fibrinogen binding with integrin α_IIbβ₃ using flow cytometry, intracellular calcium mobilization, fibronectin adhesion, dense granule secretion, and thromboxane B2 secretion. Thrombin-induced clot retraction was also observed in human platelets. Key Results: Collagen, thrombin, and U46619-stimulated human platelet aggregation were dose-dependently inhibited by G-Rk1, while it demonstrated a more effective suppression on collagen-stimulated platelet aggregation using human platelets. Moreover, G-Rk1 suppressed collagen-induced elevation of Ca²⁺ release from endoplasmic reticulum, granule release, and α_IIbβ₃ activity without any cytotoxicity. Conclusions and implications: These results indicate that G-Rk1 possess strong anti-platelet effect, proposing a new drug candidate for treatment and prevention of platelet-mediated thrombosis in cardiovascular disease.

• The Plant Pathology Journal
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• 제37권6호
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• pp.607-618
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• 2021

The pepper anthracnose fungus, Colletotrichum scovillei, causes severe losses of pepper fruit production in the tropical and temperate zones. RAC1 is a highly conserved small GTP-binding protein in the Rho GT-Pase family. This protein has been demonstrated to play a role in fungal development, and pathogenicity in several plant pathogenic fungi. However, the functional roles of RAC1 are not characterized in C. scovillei causing anthracnose on pepper fruits. Here, we generated a deletion mutant (𝜟Csrac1) via homologous recombination to investigate the functional roles of CsRAC1. The 𝜟Csrac1 showed pleiotropic defects in fungal growth and developments, including vegetative growth, conidiogenesis, conidial germination and appressorium formation, compared to wild-type. Although 𝜟Csrac1 was able to develop appressoria, it failed to differentiate appressorium pegs. However, 𝜟Csrac1 still caused anthracnose disease with significantly reduced rate on wounded pepper fruits. Further analyses revealed that 𝜟Csrac1 was defective in tolerance to oxidative stress and suppression of host-defense genes. Taken together, our results suggest that CsRAC1 plays essential roles in fungal development and pathogenicity in C. scovilleipepper fruit pathosystem.