• Journal of Microbiology and Biotechnology
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• 제25권12호
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• pp.2125-2134
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• 2015

IrrE is a highly conserved global regulator in the Deinococcus genus and contributes to survival from high doses of UV radiation, ionizing radiation, and desiccation. Drad-IrrE and Dgob-IrrE from Deinococcus radiodurans and Deinococcus gobiensis I-0 each share 66% sequence identity. However, Dgob-IrrE showed a stronger protection phenotype against UV radiation than Drad-IrrE in the D. radiodurans irrE-deletion mutant (ΔirrE), which may be due to amino acid residues differences around the DNA-binding HTH domain. Site-directed mutagenesis was used to generate a Drad-IrrE A184S single mutant, which has been characterized and compared with the ΔirrE mutant complemented strain with Drad-irrE, designated ΔirrE-E. The effects of the A184S mutation following UV radiation and mitomycin C (MMC) shock were determined. The A184S mutant displayed significantly increased resistance to UV radiation and MMC shock. The corresponding A184 site in Dgob-IrrE was inversely mutated, generating the S131A mutant, which exhibited a loss of resistance against UV radiation, MMC shock, and desiccation. qPCR analysis revealed that critical genes in the DNA repair system, such as recA, pprA, uvrA, and ddrB, were remarkably induced after UV radiation and MMC shock in the ΔirrE-IE and A184S mutants. These data suggested that A184S improves the ability against UV radiation and MMC shock, providing new insights into the modification of IrrE. We speculated that the serine residue may determine the efficiency of DNA binding, leading to the increased expression of IrrE-dependent genes important for protection against DNA damage.

• Journal of Radiation Protection and Research
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• 제24권1호
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• pp.17-22
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• 1999

이온화방사선이 동물 생식세포에 미치는 생화학적 및 형태학적 영향을 알아보기 위해 본 연구를 시행하였다. 미성숙 생쥐 (ICR, 3 주령)에 $\gamma$선을 선량 $LD_{80(30)}$으로 전신조사하였다. 방사선 조사 후 6 시간, 12 시간, 1 일, 그리고 2 일 후에 난소를 적출하였다. 난소에서 추출한 과립세포의 세포주기를 DNA에 대한 유세포 분석으로 분석하였다. 세포자연사를 확인할 수 있는 $A_0$ 세포주기는 이온화방사선이 조사된 실험군에서 대조군에 비해 현저히 높은 값을 보였다. 이온화방사선을 조사한 후 6 시간 군에서 TUNEL 면역조직화학 염색도를 나타낸 난포의 수가 대조군에 비해 현저히 증가하였다. 따라서, 본 실험의 결과 방사선 조사에 의해 유발되는 난포의 퇴화는 6 시간 이내에 급성으로 진행되는 과립세포의 세포자연사에 의해 매개됨을 알 수 있었다. 유세포분석기를 이용한 세포주기 평가는 방사선에 의해 유발되는 세포자연사 기작의 이해와 퇴화난포의 정량화를 위한 수단이 될 수 있다.

• The Plant Pathology Journal
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• 제40권5호
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• pp.486-497
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• 2024

Mosaic is the most common viral disease affecting fig plants. Although the Fig mosaic virus is the leading cause of mosaic disease, other viruses are also involved. High-throughput sequencing was used to assess viral infections in fig plants with mosaic. The genomic DNA and total RNAseq of mosaic-symptomatic fig leaves were sequenced using the Illumina platform. The analysis revealed the presence of fig badnavirus 1 (FBV-1), grapevine badnavirus 1 (GBV-1), citrus exocortis viroid (CEVd), and apple dimple fruit viroid (ADFVd). The FBV-1 and GBV-1 sequences were 7,140 bp and 7,239 bp long, respectively. The two genomes encode one open reading frame containing five major protein domains. The viroids, CEVd and ADFVd, were 397 bp and 305 bp long. Phylogenetic analyses revealed a close relationship between FBV-1 and Iranian isolates of the same species, while GBV-1 was closely related to Russian grapevine badnavirus isolates (Tem64, Blu17, KDH48, and Pal9). CEVd was closely related to other Iraqi isolates, while ADFVd was strongly related to a Spanish isolate. A registered endogenous pararetrovirus, caulimovirus-Fca1, with a size of 7,556 bp, was found in the RNA transcripts with a low expression level. This integrant was also detected in the genomes of the two lines 'Horaishi' (a female line) and 'Caprifig 6085' (a male line). Phylogenetic analyses revealed that caulimovirus-Fca1 was distinct from two other clades of different endogenous virus genera.

• 한국식품저장유통학회지
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• 제24권3호
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• pp.325-333
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• 2017

본 연구에서는 현초의 식품소재 적용과 기능성 소재의 개발을 위해 현초 에틸 아세테이트 분획물을 이용하여 활성산소종의 소거활성과 산화적 DNA 손상 보호효과 및 항균활성에 대해 검증하였다. 현초를 메탄올로 추출하여 얻어진 추출물에 대해 n-hexane, chloroform, ethyl acetate, n-butanol, water의 용매를 이용하여 순차분획을 실시하였고, 얻어진 결과물에 대하여 다양한 항산화 측정 방법을 통하여 항산화 효능을 측정한 결과 에틸 아세테이트 분획물의 경우 DPPH 라디칼 소거능, ABTS 라디칼 소거능 및 환원력에서 효과가 높게 측정 되었으며, $50{\mu}g/mL$의 농도에서 각각 80.88%, 80.12%, 28%를 저해하는 것으로 측정되었다. 이러한 항산화 효능과 함께 산화적 DNA 손상 보호효과를 검증하였고 농도별로 억제하는 경향을 나타냈다. 또한 식품 소재 및 다양한 첨가 소재로 이용하기 위하여 항균활성을 측정하였으며, 에틸 아세테이트 분획물에서 연구에 사용된 모든 균주에 대하여 저해 활성을 보였다. 이러한 활성을 가진 현초 에틸 아세테이트 분획물의 활성물질을 검증하기 위하여 phenolic compound 및 flavonoid 대조군을 이용하여 LC 분석을 하였다. 그 결과 ellagic acid와 gallic aicd가 검출 되었으며 각각 55.14 mg/g, 5.42 mg/g 측정 되었다. 이는 결과적으로 현초는 다양한 식품소재로서의 활용될 수 있으며, 본 논문은 기능성 물질로 활용을 위한 기초자료가 될 것으로 사료 된다.

• Animal cells and systems
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• 제1권3호
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• pp.451-455
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• 1997

The effects of nalidixic acid, mitomycin C, and cadmium chloride $(CdCI_2)$ on the activity of 8-hydroxyguanine $(oh^8Gua)$ endonuclease, a DNA repair enzyme for oxidatively modified guanine, $(oh^8Gua$ were studied. Nalidixic acid and mitomycin C, typical inducers of the S0S DNA repair response in E. coli, showed different effects. Nalidixic acid raised the activity of this enzyme, but mitomycin C did not show such an effect. Cadmium chloride also induced the enzyme activity, These results show that the expression of $oh^8$ Gua endonuclease is regulated by multiple factors and can be induced under stressful conditions. In an attempt to demonstrate the importance of this enzyme in defense against DNA damage and mutagenesis, we also characterized mutM mutant for its oh8 Gua endonuclease activity. The mutM mutant showed no detectable $oh^8$ Gua endonuclease activity, unlike its wild type showing high activity. In addition, paraquat, a superoxide producing compound, failed to elevate $oh^8Gua$ endonuclease activity in this mutant. These results suggest that the mutM gene is identical to the $oh^8Gua$ endonuclease gene of E. coli. Taken together with previous reports, these results suggest that $oh^8Gua$ endonuclease plays a crucial role in the protection of aerobically growing organisms from threats of oxidative DNA damage and mutation.

• The Korean Journal of Physiology and Pharmacology
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• 제8권2호
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• pp.95-100
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• 2004

Ischemic preconditioning (IPC) has been accepted as a heart protection phenomenon against ischemia and reperfusion (I/R) injury. The activation of ATP-sensitive potassium $(K_{ATP})$ channels and the release of myocardial nitric oxide (NO) induced by IPC were demonstrated as the triggers or mediators of IPC. A common action mechanism of NO is a direct or indirect increase in tissue cGMP content. Furthermore, cGMP has also been shown to contribute cardiac protective effect to reduce heart I/R-induced infarction. The present investigation tested the hypothesis that $K_{ATP}$ channels attenuate DNA strand breaks and oxidative damage in an in vitro model of I/R utilizing rat ventricular myocytes. We estimated DNA strand breaks and oxidative damage by mean of single cell gel electrophoresis with endonuclease III cutting sites (comet assay). In the I/R model, the level of DNA damage increased massively. Preconditioning with a single 5-min anoxia, diazoxide $(100\;{\mu}M)$, SNAP $(300\;{\mu}M)$ and 8-(4-Chlorophenylthio)-guanosine-3',5'-cyclic monophosphate (8-pCPT-cGMP) $(100\;{\mu}M)$ followed by 15 min reoxygenation reduced DNA damage level against subsequent 30 min anoxia and 60 min reoxygenation. These protective effects were blocked by the concomitant presence of glibenclamide $(50\;{\mu}M)$, 5-hydroxydecanoate (5-HD) $(100\;{\mu}M)$ and 8-(4-Chlorophenylthio)-guanosine-3',5'-cyclic monophosphate, Rp-isomer (Rp-8-pCPT-cGMP) $(100\;{\mu}M)$. These results suggest that NO-cGMP-protein kinase G (PKG) pathway contributes to cardioprotective effect of $K_{ATP}$ channels in rat ventricular myocytes.

• 한국응용곤충학회지
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• 제42권1호
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• pp.65-70
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• 2003

곤충자원의 대량사육을 위한 병 발생 예방과 해충의 효과적인 방제를 위하여 흰점박이꽃무지 이병충으로부터 곤충병원 사상균을 분리하였다. 전자현미경 관찰 결과 분리균주 KMA-1은 Metharizium속의 전형적인 쇠사슬형의 분생자를 paliside-like masse에 형성하였다. 따라서, 정확한 동정을 위하여 28S rRNA와 ITS염기 서열을 바탕으로 제작한 특이 프라이머쌍을 사용하여 PCR 반응을 수행하였다. 각각의 프라이머쌍을 사용한 PCR반응으로부터 특이 밴드가 검출되었으며 이 증폭 산물들의 염기 서열을 결정, 비교하였다. 분리 균주 KMA-1의 PCR산물인 28S rRNA와 ITS DNA염기서열을 GenBank데이터베이스에 등록된 염기서열 정보와의 상동성을 검색한 결과, 모두 Metarhizium anisopliae와 가장 높은 서열 상동성을 보였다. 이상의 결과로서 본 실험에서 분리 명명된 KMA-1는 M. anisopliae로 동정되었다.

• International Journal of Industrial Entomology and Biomaterials
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• 제7권2호
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• pp.181-189
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• 2003

We describe here the complete nucleotide sequence and the exon-intron structure of the luciferase gene of the firefly, Pyrocoelia rufa. The luciferase gene of the P. rufa firefly consisted of six introns and seven exons coding for 548 amino acid residues. From the translational start site to the end of last exon, however, the genomic DNA length of the P. rufa luciferase gene from the Korean and Chinese samples spans 1,968 bp and 1983 bp, respectively, and 3 amino acid residues were different to each other. Additionally, we also analyzed mitochondrial cytochrome oxidase I(COI) gene of the Chinese P. rufa fireflies. Analysis of DNA sequences from the mitochondrial COI protein-coding gene revealed 4 mitochondrial DNA sequence-based haplotypes with a maximum divergence of 0.7％. With the 20 P. rufa haplotypes found in Korea, phylogenetic analyses using PAUP and PHYLIP subdivided the P. rufa into three clades, termed clades A and B for the Korean sample, and clade C for the Chinese sample.

• BMB Reports
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• 제39권6호
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• pp.743-748
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• 2006

The complement (C) regulatory proteins decay accelerating factor (DAF, CD55) and CD59 could protect host cells using different mechanisms from C-mediated damage at two distinct levels within the C pathway. Co-expression of DAF and CD59 would be an effective strategy to help overcome host C-induced xenograft hyperacute rejection. In this study, we made a construct of recombinant expression vector containing DAF and CD59 cDNA and the stable cell lines were obtained by G418 selection. Extraneous genes integration and co-expression were identified by PCR, RT-PCR and Western blot analysis. Human c-mediated cytolysis assays showed that NIH/3T3 cells transfected stably with pcDNA3-CD59, pcDNA3-DAF, and pcDNA3-CD59DAF-DP were protected from C-mediated damage and that synchronously expressed human CD59 and DAF provided the most excellent protection for host cells as compared with either human CD59 or DAF expressed alone. Therefore, the construct represents an effective and efficacy strategy to overcome C-mediated damage in cells and, ultimately, in animals.

• Journal of Microbiology and Biotechnology
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• 제27권11호
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• pp.2060-2069
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• 2017

Newcastle disease is a serious infectious disease in the poultry industry. The commercial vaccines can only offer limited protection and some of them are expensive and need adjuvants. At present, DNA vaccines are widely used. However, the immune responses induced by DNA vaccines are too slow and low. Here, we constructed the transfer vectors with a different number of C3d as molecular adjuvants (n = 1, 2, 4, or 6), and the vectors were cloned into the optimal eukaryotic expression plasmid (pVAXI-optiF) that expressed the F gene of Newcastle disease virus (NDV), and named pVAXI-F(o)-C3d1, pVAXI -F(o)-C3d2, pVAXI-F(o)-C3d4, and pVAXI-F(o)-C3d6, respectively. Cell transfection test indicated that pVAXI-F(o)-C3d6 showed the highest expression. In vivo immunization showed that the chickens immunized with pVAXI-F(o)-C3d6 intramuscularly induced better immune responses than the chickens immunized with the other plasmids. The protective efficacy of pVAXI-F(o)-C3d6 was 80% after challenge with the highly virulent NDV strain F48E9. The results in this study showed that C3d6 could be used as a molecular adjuvant to quickly induce an effective immune response to control NDV.