• Molecules and Cells
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• 제28권5호
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• pp.431-439
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• 2009

Rice Oryza sativa accelerated cell death and resistance 1 (OsACDR1) encodes a putative Raf-like mitogen-activated protein kinase kinase kinase (MAPKKK). We had previously reported upregulation of the OsACDR1 transcript by a range of environmental stimuli involved in eliciting defense-related pathways. Here we apply biochemical, gain and loss-of-function approaches to characterize OsACDR1 function in rice. The OsACDR1 protein showed autophosphorylation and possessed kinase activity. Rice plants overexpressing OsACDR1 exhibited spontaneous hypersensitive response (HR)-like lesions on leaves, upregulation of defense-related marker genes and accumulation of phenolic compounds and secondary metabolites (phytoalexins). These transgenic plants also acquired enhanced resistance to a fungal pathogen (Magnaporthe grisea) and showed inhibition of appressorial penetration on the leaf surface. In contrast, loss-of-function and RNA silenced OsACDR1 rice mutant plants showed downregulation of defense-related marker genes expressions and susceptibility to M. grisea. Furthermore, transient expression of an OsACDR1:GFP fusion protein in rice protoplast and onion epidermal cells revealed its localization to the nucleus. These results indicate that OsACDR1 plays an important role in the positive regulation of disease resistance in rice.

• 대한수의학회지
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• 제39권2호
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• pp.247-256
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• 1999

A disease of young Holstein calves characterized by recurrent pneumonia, ulcerative and granulomatous stomatitis, enteritis with bacterial overgrowth, periodontitis, delayed wound healing, persistent neutrophilia and death at an early age had been originally described in 1983 and again in 1987. Most of these calves had stunted growth and a persistent, progressive neutrophilia (often exceeding 100,000/ml). By investigation of pedigrees, all of the affected calves have now been traced to a common sire and confirmed by polymerase chain reaction (PCR) diagnostic DNA testing to be homozygous carriers of a defective allele for bovine CD18. Neutrophils from these calves have several functional deficits and, most importantly, fail to adhere in a ${\beta}_2$-integrin dependent manner. The ${\beta}_2$-integrins represent a family of glycoproteins which participate in various leukocyte adhesion reactions during host defense. The presence or absence of ${\beta}_2$-integrin molecules can be demonstrated on the surface of neutrophils, monocytes and lymphocytes from normal or affected calves using specific monoclonal antibodies and flow cytometry, or by colloidal gold immunolabeling and scanning electron microscopy in backscatter mode. Deficiency of the ${\beta}_2$-integrins on all leukocyte types in Holstein calves is analogous to leukocyte adhesion deficiency (LAD) seen in humans. Neutrophils in bovine (BLAD) and human LAD patients are unable to adhere to the endothelial lining of the cardiovascular system thus interrupting egression of neutrophils into infected tissues. Other leukocytes, while still deficient in expression of the ${\beta}_2$-integrins, are still able to efficiently egress from the blood stream due to interactions of other adhesion molecules that are not as highly expressed on neutrophils. Both BLAD cattle and LAD children (who do not receive bone marrow transplants) often die at an early age as a result of the failure of neutrophils to extravasate into infected tissues. In 1991, Shuster, et $al^{27}$, identified two point mutations within the alleles encoding bovine CD18 in a Holstein calf afflicted with leukocyte adhesion deficiency. One mutation causes an aspartic acid to glycine substitution at amino acid 128 (D128G) in an extracellular region of this adhesion glycoprotein that is highly conserved (> 95% identity) between humans, cattle and mice. The other mutation is silent. Numerous calves with clinical symptoms of leukocyte adhesion deficiency have since been tested and all have been found homozygous for the D128G allele. In addition, calves homozygous far the D128G allele have been identified during widespread DNA testing in the United States. All cattle with the mutant allele are related to one bull, who through artificial insemination (A.I.), sired many calves in the 1950's and 1960's. The carrier frequency of the D128G CD18 allele among U.S. Holstein cattle had reached approximately 15% among active A.I. bulls and 8% among cows. By 1993, the organization of the dairy industry and the diagnostic test developed to genotype cattle, enabled virtually complete eradication of bovine leukocyte adhesion deficiency among current and future A.I. bulls.

• 생명과학회지
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• 제19권4호
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• pp.429-435
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• 2009

산화적 스트레스는 정상적인 대사 과정뿐만 아니라 외부적인 환경에 노출 되었을 때 일어나는 것으로 잘 알려져 있다. 이러한 스트레스를 극복하기 위해 생물체들은 각자의 시스템에 맞게 다양한 항산화 시스템을 진화 발전시켜 왔다. Saccharomyces cerevisiae KNU5377 균주는 고온뿐만 아니라 다양한 스트레스에 대해 내성을 가짐을 확인하였다. 대부분의 스트레스는 궁극적으로는 산화적 스트레스로 귀결된다. 이러한 측면에서 본 연구는 KNU5377 균주가 어떠한 시스템에 의해서 다른 균주보다 스트레스 내성을 가지는지를 밝히기 위해 접근하였다. 수행된 연구결과에서 KNU5377 균주는 항산화 시스템과 밀접하게 관련된 단백질(superoxide dismutase, thioredoxin system, heat shock proteins)과 항산화 관련 물질(trehalose)을 과발현함을 확인하였다. 그러나 이러한 단백질들이 어떠한 조절 시스템에 의해서 균주 특이적인 발현 양상을 보이는지는 현재까지 확인되지 않고 있다. 본 연구는 KNU5377 균주 그 자체의 중요성과 함께 균주 내의 스트레스 내성과 관련된 유용한 유전자를 탐색하여 더욱 우수한 유전자원을 발굴하는데 기여 할 것으로 보인다.

• Molecules and Cells
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• 제38권1호
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• pp.40-50
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• 2015

In the interaction between plants and pathogens, carbon (C) resources provide energy and C skeletons to maintain, among many functions, the plant immune system. However, variations in C availability on pathogen associated molecular pattern (PAMP) triggered immunity (PTI) have not been systematically examined. Here, three types of starch mutants with enhanced susceptibility to Pseudomonas syringae pv. tomato DC3000 hrcC were examined for PTI. In a dark period-dependent manner, the mutants showed compromised induction of a PTI marker, and callose accumulation in response to the bacterial PAMP flagellin, flg22. In combination with weakened PTI responses in wild type by inhibition of the TCA cycle, the experiments determined the necessity of C-derived energy in establishing PTI. Global gene expression analyses identified flg22 responsive genes displaying C supply-dependent patterns. Nutrient recycling-related genes were regulated similarly by C-limitation and flg22, indicating re-arrangements of expression programs to redirect resources that establish or strengthen PTI. Ethylene and NAC transcription factors appear to play roles in these processes. Under C-limitation, PTI appears compromised based on suppression of genes required for continued biosynthetic capacity and defenses through flg22. Our results provide a foundation for the intuitive perception of the interplay between plant nutrition status and pathogen defense.

• Journal of Nutrition and Health
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• 제44권6호
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• pp.488-497
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• 2011

Oxygen is necessary to sustain life, yet cellular oxygen metabolism creates destructive elements called free radicals. Free radicals are chemically unbalanced and carrying free electrons that can damage molecules, potentially damaging the cell itself. For this reason, many antioxidant products, including supplements and functional foods, are being developed. In particular, natural products are rich sources of pharmacologically active compounds. The purpose of this study was to investigate the antioxidant effects of target biomaterials in Korean traditional spices such as diallyl sulfide (DAS), capsaicin (CAP), and gingerol (GGR), and to investigate the response of the antioxidant defense system to oxidative stress by hydrogen peroxide ($H_2O_2$) compared to sulforaphane (SFN) in HepG2 cells. After the analysis of the cell viability using Cell Counting kit-8 (CCK-8) assay, we determined that the optimum levels were $200{\mu}M$ DAS, $25{\mu}M$ CAP, $50{\mu}M$ GGR, and $12.5{\mu}M$ SFN. Antioxidant enzymes were measured and protein expression was detected by Western blotting. All treatments showed a significant decrease in antioxidant enzyme activity such as superoxide dismutase, catalse, and glutathione peroxidase in HepG2 cells. Additionally, DAS, CAP, GGR and SFN increased the antioxidant system-related transcription factor Nrf2 which was found to be regulated by the activation of MAPK-JNK in this study. In conclusion, these results indicate the protective effects of DAS CAP, GGR, and SFN against $H_2O_2$-induced oxidative stress.

• Bulletin of the Korean Chemical Society
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• 제29권6호
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• pp.1157-1161
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• 2008

2,6-Dinitrophenol (2,6-DNP) complexes with lanthanide series including yttrium (except Pm, Tm, and Lu) have been synthesized and their crystal structures have been analyzed by X-ray diffraction methods. Singlecrystal X-ray structure determinations have been performed at 296 K on the Ce$\rightarrow$Yb species and shown them to be isomorphous, triclinic, P1, a = 8.6558(2)$\rightarrow$8.5605(3) $\AA$, b = 11.8813(3)$\rightarrow$11.6611(4) $\AA$, c = 13.9650(3) $\rightarrow$13.8341(5) $\AA$, $\alpha$ = 73.785(1)$\rightarrow$73.531(2)o, $\beta$ = 74.730(1)→74.903(2)${^{\circ}}$, $\gamma$ = 69.124(1)→ 69.670 $(2){^{\circ}}$, V = 1266.86(5)→1221.53(7) $$\AA^{3}$$, Z = 2. In Ln(III) complexes, three 2,6-DNP ligands coordinate directly to the metal ion in the bidentate fashion. The nine coordinated Ln(III) ion forms slightly distorted tri-capped trigonal prism. There are no water molecules in the crystal lattice. The dependences of metal to ligand bond lengths are discussed on the atomic number of lanthanide elements. The thermal properties of lanthanide complexes of 2,6- DNP have also studied by TG-DTG and DSC thermal analysis methods.

• Asian-Australasian Journal of Animal Sciences
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• 제14권7호
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• pp.1024-1050
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• 2001

Avian spermatozoa are characterised by high concentrations of polyunsaturated fatty acids (PUFAs), in particular docosatetraenoic (DTA, 22:4n-6) and arachidonic (AA, 20:4n-6) acids. As a result they are vulnerable to lipid peroxidation, which is considered to be an important factor of male infertility. Antioxidant systems are expressed in spermatozoa and seminal plasma and build three major levels of antioxidant defense. The first level is based on the activity of superoxide dismutase (SOD) which is, in conjunction with glutathione peroxidase (GSH-Px), catalase and metal-binding proteins, responsible for prevention of free radical formation. The second level of defence is responsible for prevention and restriction of chain reaction propagation and includes chain-breaking antioxidants such as vitamin E, ascorbic acid, glutathione and some others. The third level of antioxidant defence deals with damaged molecules, repairing or removing them from the cell and includes specific enzymes such as lipases, proteases, DNA repair enzymes etc. In the review, profiles of PUFAs and the two first lines of antioxidant defence in avian spermatozoa are characterised. Dietary manipulation of the breeder's diet (PUFA, vitamin E and selenium) as an effective means of modulating fatty acid composition and antioxidant system is also considered. Antioxidant properties of seminal plasma and efficiencies of inclusion of antioxidants into semen diluents are also characterised.

• The Korean Journal of Physiology and Pharmacology
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• 제15권1호
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• pp.23-29
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• 2011

Melatonin, which is the main product of the pineal gland, has well documented antioxidant and immune-modulatory effects. Macrophages produce molecules that are known to play roles in inflammatory responses. We conducted microarray analysis to evaluate the global gene expression profiles in response to treatment with melatonin in lipopolysaccharide (LPS) activated RAW 264.7 macrophage cells. In addition, eight genes were subjected to real-time reverse transcription polymerase chain reaction (RT-PCR) to confirm the results of the microarray. The cells were treated with LPS or melatonin plus LPS for 24 hr. LPS induced the up-regulation of 1073 genes and the down-regulation of 1144 genes when compared to the control group. Melatonin pretreatment of LPS-stimulated RAW 264.7 cells resulted in the down regulation of 241 genes and up regulation of 164 genes. Interestingly, among genes related to macrophage-mediated immunity, LPS increased the expression of seven genes (Adora2b, Fcgr2b, Cish, Cxcl10, Clec4n, Il1a, and Il1b) and decreased the expression of one gene (Clec4a3). These changes in expression were attenuated by melatonin. Furthermore, the results of real-time PCR were similar to those of the microarray. Taken together, these results suggest that melatonin may have a suppressive effect on LPS-induced expression of genes involved in the regulation of immunity and defense in RAW 264.7 macrophage cells. Moreover, these results may explain beneficial effects of melatonin in the treatment of various inflammatory conditions.

• Nutrition Research and Practice
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• 제1권1호
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• pp.19-28
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• 2007

To identify regulatory molecules which play key roles in the development of obesity, we investigated the transcriptional profiles in 3T3-L1 cells at early stage of differentiation and analyzed the promoter sequences of differentially regulated genes. One hundred and sixty-one (161) genes were found to have significant changes in expression at the 2nd day following treatment with differentiation cocktail. Among them, 86 transcripts were up-regulated and 75 transcripts were down-regulated. The 161 transcripts were classified into 10 categories according to their functional roles; cytoskeleton, cell adhesion, immune, defense response, metabolism, protein modification, protein metabolism, regulation of transcription, signal transduction and transporter. To identify transcription factors likely involved in regulating these differentially expressed genes, we analyzed the promoter sequences of up- or - down regulated genes for the presence of transcription factor binding sites (TFBSs). Based on coincidence of regulatory sites, we have identified candidate transcription factors (TFs), which include those previously known to be involved in adipogenesis (CREB, OCT-1 and c-Myc). Among them, c-Myc was also identified by our microarray data. Our approach to take advantage of the resource of the human genome sequences and the results from our microarray experiments should be validated by further studies of promoter occupancy and TF perturbation.

• 한국추진공학회지
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• 제19권4호
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• pp.24-36
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• 2015

본 연구에서는 복사 데이터베이스 기반의 LBL 모델과 근사 이론에 기초한 입자의 영향이 고려된 로켓 플룸의 적외선 스펙트럼 예측을 수행하였다. 로켓 플룸 내에 존재하는 가스 분자의 스펙트럼을 예측하기 위하여 고해상도 복사 데이터베이스를 이용하였다. 로켓 플룸 내에 존재하는 입자는 수트 입자로 모델링 하였으며 미 이론의 1항 근사 및 레일리 근사를 적용하였다. 두 이론의 적용에 대한 타당성을 검증하였으며, 이를 바탕으로 로켓 플룸의 적외선 스펙트럼을 예측하였다. 수트 입자의 영향을 고려함으로써 짧은 파장 영역 대에서 향상된 로켓 플룸의 스펙트럼 예측 결과가 도출되었다.