• Journal of Microbiology and Biotechnology
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• 제10권3호
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• pp.405-409
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• 2000

We have studied the genome of an obligately commensal thermophile, Symbiobacterium toebii. The chromosome was extracted from pure cultures of S. toebii recently established. Total DNA of S. toebii was resolved by pulsed-field gel electrophoresis (PFGE) into discrete numbers of fragments by digenstion with the endonuclease SspI, SpeI, XbaI, and HpaI. Estimated sizes of fragments produced by the four enzymes and their sum consistently yielded a total genome size of 2.8 Mb. Because restriction endonucleases NotI and SwaI, recognizing 8 bp, released too many fragments, these enzymes could not be used for the estimation of the genome size. Considering no mobility of undigested genome under PFGE, the genome of S. toebii appears to be circular. The presence of extrachromosomal DNA in S. toebii was excluded by the results of the conventional 1% agarose gel electrophoresis and the field inversion gel electrophoresis of undigested S. toebii DNA.

• Animal cells and systems
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• 제5권4호
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• pp.267-274
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• 2001

Calpains are a family of cysteine proteases existing primarily in two forms designated by the $Ca^{2+}$ concentration needed for activation in vitro, $\mu$-calpain (calpain-I) and m-calpain (calpain-II). The physiologica1 roles of calpains remain unclear. Many groups have proposed a role for calpains In apoptosis, but their patterns of activation are not well characterized. Calpains have been implicated in neutrophil apoptosis, glucocorticoid-induced thymocyte apoptosis, as well as many other apoptotic pathways. Calpain activation in apoptosis is usually linked upstream or downstream to caspase activation, or in a parallel pathway alongside caspase activation. Calpains have been suggested to be involved in DNA fragmentation (via endonuclease activation), but also as effector proteases that cleave cellular proteins involved in DNA repair, membrane associated proteins and other homeostatic regulatory proteins. Recently, our laboratory demonstrated $\mu$-calpain activation in NAD(P)H: quinone oxidoreducatse 1 (NQO1)-expressing cells after exposure to $\beta$-lapachone, a novel quinone and potential chemo- and radio-therapeutic agent. Increased cytosolic $Ca^{2+}$ in NQO1-expressing cells after $\beta$-lapachone exposures were shown to lead to $\mu$-calpain activation. In turn, $\mu$-calpain activation was important for substrate proteolysis and DNA fragmentation associated with apoptosis. Upon activation, $\mu$-calpain translocated to the nucleus where it could proteolytically cleave PARP and p53. We provided evidence that $\beta$-lapachone-induced, $\mu$-calpain stimulated, apoptosis did not involve any of the known caspases; known apoptotic caspases were not activated after $\beta$-lapachone treatment of NQO1-expressing cells, nor did caspase inhibitors have any effect on $\beta$-1apachone-induced cell death. Elucidation of processes by which $\beta$-1apachone-stimulated $\mu$-calpain activation and calpains ability to activate endonucleases and induce apoptosis independent of caspase activity will be needed to further develop/modulate $\beta$-lapachone for treatment of human cancers that over-express NQO1.

• IMMUNE NETWORK
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• 제11권5호
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• pp.253-257
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• 2011

Background: The active metabolite (1, 25- dihydroxycholecalciferol) of vitamin D (25-hydroxycholecalciferol) leads to activation of macrophages and deficiency of vitamin D seems to be involved in the risk of tuberculosis. The effects of vitamin D are exerted by interaction with the vitamin D receptor (VDR) and may be influenced by polymorphism in the VDR gene. In this study, variation in the VDR gene was investigated in Korean population with tuberculosis. Methods: We typed three VDR polymorphisms of restriction endonuclease sites for TaqI, BsmI and FokI in 155 patients with tuberculosis and 105 healthy volunteers. Results: The frequencies of FokI genotypes determined from TB patients were 29.13% for FF, 56.31% for Ff, and 14.56% for ff. We observed 1.4-fold increased prevalence of the Ff genotype in TB patients compared with normal healthy groups (p=0.0857). However, there was no significant association between the genotype groups, TB patient and normal control, for FokI polymorphism. There was also no significant association between VDR gene and tuberculosis in another polymorphism (BsmI and TaqI). Conclusion: Three polymorphisms (TaqI, BsmI and FokI) in the VDR gene do not appear to be responsible for host susceptibility to human tuberculosis in Korean population.

• Asian-Australasian Journal of Animal Sciences
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• 제30권8호
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• pp.1183-1189
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• 2017

Objective: Owing to the public availability of complete genome sequences, including avian species, massive bioinformatics analyses may be conducted for computational gene prediction and the identification of gene regulatory networks through various informatics tools. However, to evaluate the biofunctional activity of a predicted target gene, in vivo and in vitro functional genomic analyses should be a prerequisite. Methods: Due to a lack of quail genomic sequence information, we first identified the partial genomic structure and sequences of the quail SH3 domain containing ring finger 2 (SH3RF2) gene. Subsequently, SH3RF2 was knocked out using clustered regularly interspaced short palindromic repeat/Cas9 technology and single cell-derived SH3RF2 mutant sublines were established to study the biofunctional activity of SH3RF2 in quail myoblast (QM7) cells during muscle differentiation. Results: Through a T7 endonuclease I assay and genotyping analysis, we established an SH3RF2 knockout (KO) QM7#4 subline with 61 and 155 nucleotide deletion mutations in SH3RF2. After the induction of myotube differentiation, the expression profiles were analyzed and compared between regular QM7 and SH3RF2 KO QM7#4 cells by global RNA sequencing and bioinformatics analysis. Conclusion: We did not detect any statistically significant role of SH3RF2 during myotube differentiation in QM7 myoblast cells. However, additional experiments are necessary to examine the biofunctional activity of SH3RF2 in cell proliferation and muscle growth.

• 한국수정란이식학회지
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• 제31권3호
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• pp.179-183
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• 2016

Even though klotho deficiency in mice exhibits multiple aging-like phenotypes, studies using large animal models such as pigs, which have many similarities to humans, have been limited due to the absence of cell lines or animal models. The objective of this study was to generate homozygous klotho knockout porcine cell lines and cloned embryos. A CRISPR sgRNA specific for the klotho gene was designed and sgRNA (targeting exon 3 of klotho) and Cas9 RNPs were transfected into porcine fibroblasts. The transfected fibroblasts were then used for single cell colony formation and 9 single cell-derived colonies were established. In a T7 endonuclease I mutation assay, 5 colonies (#3, #4, #5, #7 and #9) were confirmed as mutated. These 5 colonies were subsequently analyzed by deep sequencing for determination of homozygous mutated colonies and 4 (#3, #4, #5 and #9) from 5 colonies contained homozygous modifications. Somatic cell nuclear transfer was performed to generate homozygous klotho knockout cloned embryos by using one homozygous mutation colony (#9); the cleavage and blastocyst formation rates were 72.0% and 8.3%, respectively. Two cloned embryos derived from a homozygous klotho knockout cell line (#9) were subjected to deep sequencing and they showed the same mutation pattern as the donor cell line. In conclusion, we produced homozygous klotho knockout porcine embryos cloned from genome-edited porcine fibroblasts.

• 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.

• 한국자원식물학회지
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• 제21권1호
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• pp.41-46
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• 2008

차나무의 분자학적 유연관계 및 유전적 다양성을 알아보기 위하여 한국에서 자생하는 차나무 집단 21개 지역 차나무에 대하여 DFR 유전자 부위를 이용하여 PCR-RFLP분석을 하였다. DFR 4+5 primer 쌍을 이용하여 증폭결과 DFR유전자의 크기는 약 1.4kb에서 PCR산물을 획득하였다. PCR산물에 제한효소 Hpa II 및 Mse I를 이용하여 RFLP분석 결과 차나무 집단간 또는 집단내 차나무간의 유전적 다양성을 보였다. Hpa II 제한효소를 이용한 RFLP 밴드패턴은 3가지 형태로 구분되었으며, 같은 차나무 집단내에서도 유전적 다양성이 나타났다. Mse I 제한효소를 이용한 밴드패턴은 6가지의 형태로 다양성을 보였으며, 웅포집단 차나무의 경우 집단 내 다양성이 2가지 형태로 나타나 같은 집단내에서의 유전적 변이는 적은 것으로 보인다. 본 연구에서 사용한 2가지의 제한효소의 결과 차나무의 집단간 또는 같은 집단내의 차나무간에서 유전적 다양성을 확인할 수 있었다.

• 한국미생물·생명공학회지
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• 제26권2호
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• pp.117-121
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• 1998

김치로부터 분리한 Lactobacillus plantarum bacteriophage SC 921은 M.O.I가 0.2일 경우 용균효과가 빠르게 진행됨을 알 수 있었고, SDS-PAGE를 실시하여 phage particle protein을 조사해 본 결과 4개의 major protein으로 구성되어 있는데 이들은 각각 48, 34, 32, 29 kDa으로 구성되어 있다. Exo III로 30분간 반응시킨 후 S1 nuclease를 처리하여 DNA의 형태를 조사해 본 결과 intact DNA는 linear form의 double strand를 유전전달 물질로 가지고 있었다. 제한효소에 대한 절단 효과를 조사한 결과, Sma I에 대해서 1개, Xba I, Cla I, Kpn I, EcoRI에 대해서 각각 2, 4, 5, 6개의 절단부위를 가지고 있으며, Hind III에 대해서는 절단부위가 매우 많은 것을 알 수 있었다. Hind III를 이용하여 intact DNA의 genome size를 측정해본 결과 약 66.5 kbp정도였다. 위의 실험결과와 restriction enzyme mapping을 통해 기존에 알려진 bacteriophage B2와 비교해본 결과 숙주 균주는 같으나 단백질적인 구조나 유전전달물질로 본 구조는 서로 다름을 알 수 있었다.

• Journal of Photoscience
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• 제10권2호
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• pp.195-198
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• 2003

In the cellular response to DNA damaging agents, cells undergo cell cycle arrest or apoptosis against irrepairable DNA damage. RpS3 is known to function as UV DNA repair endonuclease III and ribosomal protein S3. In this study, we used normal and rpS3-overexpressed 293T cells to examine the role of rpS3 in response to DNA damaging agents. When 293T cells transfected with rpS3 were irradiated with UV, the pattern of cell cycle was dramatically changed in comparison with un-transfected 293T cells. We also found that the expression of rpS3 in normal cells was increased by treatment with DNA damaging agents. By means of Western and Northern blot analyses in rat tissues, we showed the expression pattern of rpS3 protein and its mRNA. These data suggest that DNA repair and cell cycle arrest are interrelated to each other through rpS3, and the increased expression of rpS3 seems to regulate the cell cycle arrest by DNA damaging agents.

• 대한수의학회지
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• 제32권3호
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• pp.369-376
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• 1992

This paper dealt with plasmid DNA profile in 98 Salmonella(S) isolated from pigs and cattle sources in Taegu, Gyeongbook and Gyeongnam during the period from 1984 to 1987. Also we were studied for restriction enzyme analysis of the plasmid DNA, and mouse infection, Sereny test and normal setum resistance test in guinea pig for S typhimurium and S enteritidis harbored or cured 60 megadalton(Md) plasmid and 36 Md plasmid, respectively. Of the 13 Salmonella isolated from cattle, 7 Salmonella harbored one or more plasmids and molecular sizes of the large plasmids were 60 Md for S typhimurium and 36 Md for S enteritidis. Of the 85 Salmonella isolated from pigs, 47 Salmonella were confirmed as being one or more plasmids, and all the S typimurium stains harbored 60 Md plasmid. In enzyme digestion with 8 types of restriction endonuclease for 60 Md plasmid DNA of S typhimurium, cleavage patterns were varied to enzymes, and the DNA was segmented into 4 to 15 fragments. In restriction enzyme analysis of 36 Md plasmid DNA obtained from four strains of S. enteritidis, the DNA showed the same cleavage patterns obtained with Eco RI, Hind III and Bam H I, and was segmented into 3 to 5 fragments. In virulence for mice by measuring the 50% lethal dose ($LD_{50}$), the $LD_{50}$ values obtained for 60 Md virulence-associated plasmid harbored strains of S typhimurium and 36 Md virulence-associated plasmid of S enteritidis were up to $10^4$-fold lower than the values obtained for the plasmid-cured strains of the same serotype. Only the plasmid harbored strains were resistant to the bactericidal activity of 90% guinea pig serum, and only they gave positive responses in sereny test. We suggested that their plasmid DNA might be associated with virulence for mice.