• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.280-282
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• 2005

초파리 초기 발생과정은 gap 유전자, pair-rule 유전자, polarity 유전자의 세 가지 유전자 그룹에 의해서 조직화 된다. Gap 유전자들에 의해 pair-rules 유전자들의 발현이 조절되며, 이들에 의해 결국 polarity 유전자들의 발현을 조절함으로써, 정확한 위치에서 각 기관의 형성을 유도한다. 특히 분열 14단계에서는 pair-rule 유전자 중의 하나인 eve 유전자의 발현이 조절되는데, eve 유전자는 배아의 분할의 줄무늬를 형성시키는 유전자에 해당된다. 본 논문에서는 eve 유전자의 발현조절자인 hunchback, giant, kruppel, bicoid의 gap 유전자들로 구성된 조절 네트워크를 S-system을 이용하여 모델링하였다. 이를 통해 각 유전자들의 발현 데이터로부터 파라미터들을 진화 연산을 통해 예측하고, 각 유전자들의 발현에 대한 시뮬레이션 결과를 보여준다. 예측된 결과와 실제 데이터의 비교는 전체적으로 패턴이 서로 유사함을 보여주고 있다.

• Korean Journal of Microbiology
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• v.48 no.4
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• pp.319-324
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• 2012

In this study, we investigated molecular divergences and phylogenetic characteristics of the 16S ribosomal RNA (rRNA) and RNA polymerase beta subunit (rpoB) gene sequences from the order Oscillatoriales (Cyanobacteria). The rpoB of Oscillatoriales showed higher genetic divergence when compared with those of 16S rRNA (p-distance: rpoB=0.270, 16S=0.109), and these differences were statistically significant (Student t-test, p<0.001). Phylogenetic trees of 16S rRNA and rpoB were generally compatible; however, rpoB tree clearly separated the compared Oscillatoriales taxa, with higher phylogenetic resolution. In addition, parsimony analyses showed that rpoB gene evolved 2.40-fold faster than 16S rRNA. These results suggest that the rpoB is a useful gene for the molecular phylogenetics and species discrimination in the order Oscillatoriales.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2000.05a
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• pp.220-223
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• 2000

타입-2 퍼지집합을 이용하여 퍼지논리시스템(Fuzzy Logic System : FLS)을 구현하기 위한 연구들이 R. I John, N. Karnik, J. Mendel 등에 의해 현재 진행되고 있다. 타입-2 집합을 이용한 타입-2 FLS은 기존의 타입-1 FLS보다 제어규칙이나 소속함순가 가지고 있는 불확실성을 표현하는데 있어서 더 효과적이다. 그러나, 타입-2 FLS 역시 타입-1 FLS이 가지고 있는 문제점인 설계시 전문가에게 의존하여 시간과 비용이 많이 소요되고, 제어기의 구성요소들을 효율적으로 생성하기가 어렵다는 문제점을 더욱 심각하게 가지고 있다. 또한, 그 문제점을 해결하기 위한 연구들도 아직 미진한 상태이다. 본 논문에서는 타입-2 FLS의 설계를 위해 유전자 알고리즘을 사용하는 방법을 제안한다. 타입-2 FLS를 설계하기 위해서는 소속함수와 제어규칙을 생성하여야 한다. 본 논문에서는 유전자 알고리즘을 사용하여 타입-2 퍼지제어규칙과 소속함수를 설계하는 방법을 제안한다. 먼저, 유전자 알고리즘에서 사용할 수 있는 유전자의 형태로 타입-2 퍼지제어규칙과 소속함수를 표현하기 위한 인코딩방법을 제안하고, 각각의 염색체를 진화시키기 위한 교차 연산자와 돌연변이 연산자를 정의한다. 그리고, 제안된 방법을 함수근사문제에 적용하여 유효성과 성능을 평가, 검증한다.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.3
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• pp.226-233
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• 2007

Purpose: Dual reporter gene imaging has several advantages for more sophisticated molecular imaging studies such as gene therapy monitoring. Herein, we have constructed hepatoma cell line expressing dual reporter genes of sodium iodide symporter (NIS) and enhanced green fluorescence protein (EGFP), and the functionalities of the genes were evaluated in vivo by nuclear and optical imaging. Materials and Methods: A pRetro-PN vector was constructed after separating NIS gene from pcDNA-NIS. RSV-EGFP-WPRE fragment separated from pLNRGW was cloned into pRetro-PN vector. The final vector expressing dual reporter genes was named pRetro-PNRGW. A human hepatoma (HepG2) cells were transfected by the retrovirus containing NIS and EGFP gene (HepG2-NE). Expression of NIS gene was confirmed by RT-PCR, radioiodine uptake and efflux studies. Expression of EGFP was confirmed by RT-PCR and fluorescence microscope. The HepG2 and HepG2-NE cells were implanted in shoulder and hindlimb of nude mice, then fluorescence image, gamma camera image and I-124 microPET image were undertaken. Results: The HepG2-NE cell was successfully constructed. RT-PCR showed NIS and EGFP mRNA expression. About 50% of cells showed fluorescence. The iodine uptake of NIS-expressed cells was about 9 times higher than control. In efflux study, $T_{1/2}$ of HepG2-NE cells was 9 min. HepG2-NE xenograft showed high signal-to-background fluorescent spots and higher iodine-uptake compared to those of HepG2 xenograft. Conclusion: A hepatoma cell line expressing NIS and EGFP dual reporter genes was successfully constructed and could be used as a potential either by therapeutic gene or imaging reporter gene.

• Clinical and Experimental Pediatrics
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• v.46 no.1
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• pp.24-32
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• 2003

Purpose : Nosocomial infection with Staphylococcus aureus, especially methicillin resistant S. aureus, has become a serious concern in the neonatal intensive care unit. The aim of this study is to investigate the virulence factors, and the relationship between the antibiotic resistance and the associated genes of Staphylococcus aureus isolated from nasal cavity of neonates. Methods : Fifty one isolates of S. aureus were obtained from nasal swab taken in 28 neonates in the NICU and nursery of Pusan National University Hospital between February and May, 2001. They were tested in regard to antibiotic susceptibility, coagulase test and typing, plasmid DNA profile, as well as reactivity to enterotoxin A-E(sea, seb, sec, sed, see) genes and toxic shock syndrome toxin-1(tst) gene by polymerase chain reaction(PCR). Associated genes such as mecA, mecR1, mecI, and femA were also determined by PCR. The origin of MRSA strains was assessed using DNA fingerprinting by arbitrarily-primed polymerase chain reaction(AP-PCR). Results : Twenty three(45.1%) and six(11.8%) isolates were resistant to oxacillin and vancomycin respectively. Multidrug resistance to three or more of the antibiotics tested was observed in 51.0% of the isolates. Forty two isolates were coagulase positive and twenty two isolates had mecA gene. Sixteen isolates had both mecA and femA genes and had type I-III plasmids. 64.7% of isolates carried sec gene, and 80.4% carried tst gene. DNA fingerprinting by AP-PCR for 12 MRSA strains showed 10 distinct patterns, suggesting different origins. Conclusion : We confirmed that the prevalence of nasal carriage of S. aureus and the incidence of antimicrobial-resistant S. aureus, especially vancomycin resistance, is very high in neonates who were admitted in NICU and nursery. It is possible that these pathogens are responsible for serious nosocomial infections in neonates. The need for improved surveillance and continuous control of pathogens is emphasized.

• Korean Journal of Plant Tissue Culture
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• v.28 no.2
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• pp.87-90
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• 2001

BcGRl gene encoding cytosolic glutathione reductase of Chinese cabbage (Brassica campestris var. Pekinensis cv. Seoul) was placed under the control of the CaMV 35S promoter and introduced into tobacco (Nicotiana tabacum L. cv. Samsun) via Agrobacterium-mediated transformation. T$_{0}$ 32 independent plants transformed with BcGRl gene were selected with kanamycin and they were confirmed by polymerase chain reaction (PCR) and Southern blot analysis. Northern blot analysis revealed that the constitutive expression of BcGRl gene and there was no relationship between the copy number of introduced gene and the levels of BcGRl transcripts.

• Korean Journal of Microbiology
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• v.21 no.4
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• pp.229-237
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• 1983

Total tRNA genes from Aspergillus nidulans were cloned for the further investigation of the structure and expression of Aspergillus tRNA genes. Aspergillus DNA was isolated from spores and cloned into pBR322 plasmid DNA using BamHI and $T_4$ ligase. The recombinant hybrid DNA was transformed into E. coli HB101 and some 30,000 transformants were initially selected. Of these, about 5,300 E. coli clones containing Aspergillus DNA inserted into plasmid pBR322 at BamHl site have been isolated. The hybridization data obtained from the labeled Aspergillus $^{32}P-tRNA$ indicated that 105 colonies carried the total tRNA genes. From the data above and cohybridization experiment, tRNA genes of Aspergillus nidulans seem to be twice more clustered than those of yeast.

• Journal of Periodontal and Implant Science
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• v.37 no.sup2
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• pp.339-351
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• 2007

Cytolethal distending toxin(CDT)은 세포 주기 중 G2에서 M 기로의 전환을 막아 세포의 증식을 억제할 수 있는 세균 단백 독소의 일종이다. 구강 미생물 중 유일하게 Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans)만이 이 CDT를 생성 할 수 있는 것으로 알려져 있다. A. actinomycetemcomitans는 localized aggressive periodontitis (LAP)의 원인균으로 여겨지며 비 운동성의 그람 음성 구간균이고 $37^{\circ}C$, 5% $CO_2$ 하에 성장이 왕성하다. A. actinomycetemcomitans의 CDT는 3개의 인접한 유전자인 cdtA, cdtB, cdtC에 의해 형성 되며 각각의 유전자에 대한 단백질의 기능은 아직 완전히 밝혀지지 않았다. 현재까지 연구에 의하면 cdtA는 CDT의 세포부착과 관련이 있는 것으로 여겨지며 이 유전자의 기능 이상 시 CDT의 독성 효과가 현저히 감소한다고 알려져 있다. 따라서 본 연구는 A. actinomycetemcomitans의 cdtA 유전자를 클로닝, 단백질 발현하여 향후 치주질환의 발병 과정에서 CdtA의 역할을 규명하고 질환의 예방 및 치료법에 도움을 주고자 하였다. A. actinomycetemcomitans Y4균주를 cdtA 유전자 클로닝을 위해 사용하였다. A. actinomycetemcomitans의 genomic DNA는 genomic DNA 추출 kit를 사용하여 분리하고 cdtA에 특이적인 primer를 이용하여 PCR을 통해 cdtA 유전자를 증폭하였다. 증폭된 cdtA 유전자를 T-vector에 클로닝 하였으며, 클로닝 된 cdtA 유전자는 단백질 발현을 위해 pRSET Avector에 서브클로닝 한 후 발현 균주인 BL21(DE3)를 이용하여 발현시켰다. 발현 후 Ni-NTA AP conjugate를 이용한 Western blot을 통해 pRSET-CDTA를 확인하였다.

• The Journal of the Korea Contents Association
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• v.17 no.10
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• pp.289-299
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• 2017

To verify the association between susceptibility to chronic myeloid leukemia (CML) and GSTM1, GSTT1 gene polymorphisms in Asian populations, 9 papers published until July 2017 were cited in a meta-analysis. The null present types of the GSTM1, GSTT1 gene were analyzed individually. The significant association was found between CML and GST polymorphism (GSTM1; OR=1.306, 95% CI=1.091-1.563, p=0.004, GSTT1; OR=1.987, 95% CI=1.438-2.746, p=0.000). In addition, there was association between CML and the null type of the combination GSTM1-GSTT1 polymorphisms (OR=4.191, 95% CI=2.833-6.201, p=0.000). Thus, genetic polymorphisms of the GSTM1, GSTT1 and combination GSTM1-GSTT1 polymorphism in Asian populations may be risk factors for CML.

• Korean Journal of Breeding Science
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• v.42 no.1
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• pp.50-55
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• 2010

The R-r:standard (R-r:std) allele of maize R gene complex consists of S subcomplex and P component; the S subcomplex regulates anthocyanin pigmentation of seed aleurone layer, and the P component confers pigmentation of the other plant parts. The S subcomplex contains two functional genes, S1 and S2 components. In the presence of Pl gene some alleles of R gene induce anthocyanin pigmentation of pericarp. In the present study, the effects of different R alleles on the anthocyanin pigmentation of pericarp in the presence of Pl gene were analyzed in order to identify the R gene component responsible for pericarp pigmentation. The results show that R-ch and r-ch alleles condition similar degrees of pericarp pigmentation, and that R-r:Ecuador (R-r:Ec) conditions stronger pigmentation. The r-ch allele, which is inferred that its S subcomplex has lost function but the P component is normal, induces pericarp pigmentation in the presence of Pl gene. On the contrary, the R-g:g1111 allele, derived from R-r:Ec and inferred that its S subcomplex functions normal but the P component has lost its function, did not induce pericarp pigmentation in the presence of Pl gene. Moreover, PCR analysis of genomic DNA's of R-ch and r-ch indicate that R-ch maintains both P and S1 components, whereas r-ch lacks for the S1 component. Taken together, The results suggest that the P components of R alleles inducing pericarp pigmentation in the presence of Pl gene are responsible for pericarp pigmentation.