• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.472-475
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• 2004

Microarray-based DNA chips provide an architecture for multi-analyte sensing. In this paper, we report a new approach for DNA chip microarray fabrication. Multifunctional DNA chip microarray was made by immobilizing many kinds of biomaterials on transducers (particles). DNA chip microarray was prepared by randomly distributing a mixture of the particles on a chip pattern containing thousands of m-scale sites. The particles occupied a different sites from site to site. The particles were arranged on the chip pattern by the random fluidic self-assembly (RFSA) method, using a hydrophobic interaction for assembly.

• 생태와환경
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• 제54권3호
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• pp.156-169
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• 2021

동물플랑크톤 군집 연구에 DNA 바코딩과 같은 DNA 분석 기법의 적용은 분류형태학을 기반으로 하는 전통적인 종동정 시 발생할 수 있는 문제(e.g. 개체의 표현형 가소성에 의한 오동정, 유사종 및 자매종, 유생 시기의 종 동정의 어려움)를 보완할 수 있다. 최근 DNA 시퀀싱 기술의 발전으로 다양한 수생태계의 동물플랑크톤 군집은 물론, 육안 및 현미경을 통해 구분하는 데 한계가 있는 동물플랑크톤의 위 내용물에 대한 DNA 기반 군집 분석 또한 가능하게 되었으며, 이는 동물플랑크톤의 섭식 먹이원 분석을 통한 생물학적 상호작용을 이해를 돕는다. 본 논문은 동물플랑크톤 연구에 DNA 분석 기법이 활용된 사례(e.g. DNA 바코딩을 이용한 계통분류학적 연구, 메타바코딩을 이용한 군집 분석, 위 내용물 분석)를 소개하고 분석 방법을 요약하여, 최종적으로 향후 이를 활용하고자 하는 연구자들에게 연구 접근성을 높일 수 있도록 방법론적인 기초 지식을 제공하고자 하였다.

• BMB Reports
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• 제29권1호
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• pp.1-10
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• 1996

The binding interaction of ethidium to a series of synthetic deoxyoligonucleotides containing a B-Z junction between left-handed Z-DNA and right-handed B-DNA, was studied. The series of deoxyoligonucleotides was designed so as to vary a dinucleotide step immediately adjacent to a B-Z junction region. Ethidium binds to the right-handed DNA forms and hybrid B-Z forms which contain a B-Z junction, in a highly cooperative manner. In a series of deoxyoligonucleotides, the binding affinity of ethidium with DNA forms which were initially hybrid B-Z forms shows over an order of magnitude higher than that with any other DNA forms, which were entirely in B-form DNA The cooperativity of binding isotherms were described by an allosteric binding model and by a neighbor exclusion model. The binding data were statistically compared for two models. The conformation of allosterically converted DNA forms under binding with ethidium is found to be different from that of the initial B-form DNA as examined by CD spectra. The ratio of the binding constant was interestingly correlated to the free energy of base unstacking and the conformational conversion of the dinucleotide. The more the base stacking of the dinucleotide is unstable, or the harder the conversion of B to A conformation, the higher the ratio of the binding constant of ethidium with the allosterically converted DNA forms and with the initial B-Z hybrid forms. DNA sequence around a B-Z junction region affects the binding affinity of ethidium. The results in this study demonstrate that ethidium could preferentially interact with unusual DNA structures.

• Animal cells and systems
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• 제6권3호
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• pp.263-269
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• 2002

The p53 tumor suppressor gene is among the most frequently mutated and studied genes in human cancer, but the mechanisms by which it sur presses tumor formation remain unclear. DNA damage regulates both the protein levels of p53 and its affinity for specific DNA sequences. Stabilization of p53 in response to DNA damage is caused by its dissociation from Mdm2, a downstream target gene of p53 and a protein that targets p53 for degradation in the proteosome. Recent studies have suggested that phosphorylation of human p53 at Ser20 is important for stabilizing p53 in response to DNA damage through disruption of the interaction between Mdm2 and p53. We generated mice with an allele encoding changes at Ser20, known to be essential for p53 accumulation following DNA damage, to enable analyses of p53 stabilization in vivo. Our data showed that the mutant p53 was clearly defective for full stabilization of p53 in response to DNA damage. We concluded that Ser20 phosphorylation is critical for modulating the negative regulation of p53 by Mdm2, probably through phosphorylation-dependent inhibition of p53-Mdm2 interaction in the physiological context.

• Journal of Microbiology and Biotechnology
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• 제17권10호
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• pp.1607-1615
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• 2007

We investigated the applicability of the TEM-l ${\beta}$-lactamase fragment complementation (BFC) system to develop a strategy for the screening of protein-protein interactions in bacteria. A BFC system containing a human Fas-associated death domain (hFADD) and human Fas death domain (hFasDD) was generated. The hFADD-hFasDD interaction was verified by cell survivability in ampicillin-containing medium and the colorimetric change of nitrocefin. It was also confirmed by His pull-down assay using cell lysates obtained in selection steps. A coiled-coil helix coiled-coil domain-containing protein 5 (CHCH5) was identified as an interacting protein of human uracil DNA glycosylase (hUNG) from the bacterial BFC cDNA library strategy. The interaction between hUNG and CHCH5 was further confirmed with immunoprecipitation using a mammalian expression system. CHCH5 enhanced the DNA glycosylase activity of hUNG to remove uracil from DNA duplexes containing a U/G mismatch pair. These results suggest that the bacterial BFC cDNA library strategy can be effectively used to identify interacting protein pairs.

• Bulletin of the Korean Chemical Society
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• 제24권5호
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• pp.579-582
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• 2003

Norfloxacin, that inhibits the action of topoisomerase Ⅱ, binds to wide variety of DNA. The binding mode of this drug to double- and super-coiled DNA (ds- and scDNA) is compared in this study by various spectroscopic methods, including absorption, fluorescence, and circular dichroism(CD) spectroscopy. Hypochromism in the absorption band, negative and positive induced CD bands (respectively in 240-260 nm and 270-300 nm region) are apparent for the norfloxacin that bound to both the dsDNA and scDNA. A decrease in fluorescence is also noticed in the presence of both DNAs. Since the spectroscopic characteristics are the same for both complexes, it is imperative that the binding mode of the norfloxacin is similar in ds- and scDNA. In the presence of $Mg^{2+}$, which is a cofactor in the topoisomerase Ⅱ action, the fluorescence intensity of the scDNA-norfloxacin complex increased and the resulting fluorescence intensity and shape was identical to that in the absence of scDNA. Therefore, the addition of an excess amount of $Mg^{2+}$ may result in the extrusion of norfloxacin from scDNA.

• Animal cells and systems
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• 제7권1호
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• pp.81-87
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• 2003

While screening proteins that interact with DnaA protein, the initiator protein for Escherichia coil chromosomal DNA replication, we found a 52-kD sized protein which bound to DnaA protein in a salt-dependent manner. This protein was identified as trigger factor, a ribosome-associated peptidyl-prolyl- cisltrans isomerase with chaperone activity. Trigger factor was overproduced and purified to near homogeneity, and its effect on the function of DnaA protein was examined, Enhanced binding of DnaA protein to DnaA box with no apparent supershift in the gel-shift experiments suggested that trigger factor, by virtue of its chaperone activity, exerts a change on DnaA protein thus increasing its binding affinity for DnaA box.

• 대한화학회지
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• 제29권3호
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• pp.304-310
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• 1985

송아지 흉선 nucleohistone의 DNase 1에 對한 susceptibility와 相互作用의 cooperativity에 미치는 spermine의 效果를 nucleostone의 構造變移와 關聯시켜 調査하였다. 이들 data로 부터 nucleohistone은 遊離 DNA와는 對照的으로 spermine에 의하여 monomoclecular condensation을 일으키지 않고 intermolecular aggregation을 이루며 nucleohistone의 DNase 1과의 相互作用 cooperativity가 spermine에 의하여 增加됨을 推理할 수 있다. Nucleohistine의 histone 部分의 cooperativity에 關한 機能的 役割을 究明하기 위하여 histone 部分을 단실化시킨 DNS-nucleohistone을 製造하여 DNase 1 과의 相互作用을 調査하여 보았는바 negative cooperativity로 나타났다. 이로 부터 nucleohistone의 histone部分은 nucleohistone의 cooperativity에 影響을 미치리라고 推理할 수 있다.

• 생명과학회지
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• 제24권11호
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• pp.1187-1192
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• 2014

고추는 한국, 중국, 멕시코를 포함한 온대 및 아열대 지역을 중심으로 전세계적으로 전형적인 향신료로 식용되고 있으며 그 생산량 및 사용량은 해마다 증가하는 추세에 있다. 고추역병균인 Phytophthora capsici는 고추의 생산에 있어, 질적, 양적으로 많은 피해를 야기하는 식물병원균으로 알려져 있다. 난균강에 속하는 이 병원균은 기주식물의 뿌리, 줄기, 잎과 함께 과실에 이르기까지 식물체 전체를 가해한다. 고추역병의 발병을 분자수중에서 이해하기 위해서는, 발병과정에서 발현되는 유전자에 대한 연구분석이 필수적이며, 이를 위해 최근 개발되어 응용되고 있는 발현서열표지(expressed sequence tags, ESTs)의 분석을 시도하였다. 고추역병균을 접종한후 3일째 발병초기의 고추잎으로부터 추출한 total RNA를 이용하여 고추-고추역병균 발병초기 cDNA library를 구축하였다. 이 cDNA library에서 무작위로 선발된 5,760 clone에 대하여 말단 염기서열 분석을 수행하여 5,148개의 양질의 염기서열을 확보하고 contig assembly에 적용한 결과, 2,990개의 unigenes을 확보하였다. 이들 2,990개의 unigenes에 대한 BLASTX를 이용한 상동성 분석결과, 2,409개가 기존에 알려진 서열과 matching을 보였으며, 이중 606개가 기능적으로 구분되었다.

• BMB Reports
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• 제34권1호
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• pp.15-20
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• 2001

One of the innate immune reactions in invertebrates is the pro-phenoloxidase (pro-PO) activation system that is involved in the generation of superoxide, melanin synthesis, and the subsequent sequestration of foreign matter entering the hemocoel of the invertebrates. However, the molecular mechanism of this biological reaction is still obscure. To expand our understanding of the biological roles of the pro-PO activation system in invertebrates, we performed a yeast two-hybrid screening by using three regions of pro-PO as bait and a yeast two-hybrid cDNA library from Tenebrio molitor larvae as prey We isolated a novel partial cDNA clone that encodes a glycine-rich protein that interacted with the active phenoloxidase (termed phenoloxidase interacting protein, POIP). POIP consists of two domains: One is an N-terminal unique domain and the other is a C-terminal glycine-rich domain. The C-terminal glycine-rich domain showed sequential homology with those of insect antifungal proteins. Also, the yeast two-hybrid screen in a reverse orientation (using POIP as bait) yielded PO, suggesting that the PO-POIP interaction is specific. By using a 315 bP PCR fragment of the N-terminal unique region of POIP, we cloned the full-length cDNA of POIP from the Tenebruo cDNA library constructed by using E. coli injected larvae. The interaction analysis between PO, and a truncated fragment lacking the N-terminal unique region of POIP, indicated that the N-terminal unique region is necessary for interaction between PO and POIP. The expression level of the POIP mRNA is increased by bacterial injection into T. molitor larvae. This suggests that POIP might be engaged in the humoral defense reaction.