• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.92.1-92.1
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• 2013

Molecular electronics has been the subject of intese research for many years because of the fundamental interest in molecular charge transport and potential applications, such as (bio)nanosensors and molecular memory devices. Molecular electronics requires a method for making reliable eletrical contacts to singlemolecules. To date, several approaches have been reported: scanning-probe microscopy, mechanical break junctions, nano patterning, and direct deposition of electrode on a self-assembled monolayers. However, most methods are laborious and difficult for large-scale application and more importantly, cannot control the number of moleucles in the junction. Recently, DNA has been used as a template for metallic nanostructures (e.g., Ag, Pd, and Au nanowires) through DNA metallization process. Furthermore, oligodeoxynucleotides have been tethered to organic molecules by using conventional organic reactions. Collectively, these techniques should provide an efficient route toward reliable and reproducible molecular electronic devices with large-scale fabrication. Therefore, I will present a paradigm for the fabrication of moleuclar electronic devices by using micrometer-sized DNA-singe organic molecule and DNA triblock structures.

• Molecules and Cells
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• 제26권4호
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• pp.350-355
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• 2008

Chk2 is a well characterized protein kinase with key roles in the DNA damage response. Chk2 is activated by phosphorylation following DNA damage, and relays that signal to various substrate proteins to induce cell cycle arrest, DNA repair, and apoptosis. In order to identify novel components of the Chk2 signaling pathway in Drosophila, we screened 2,240 EP misexpression lines for dominant modifiers of an adult rough eye phenotype caused by Chk2 overexpression in postmitotic cells of the eye imaginal disc. The rough eye phenotype was suppressed by mutation of the ATM kinase, a well-described activator of Chk2. Twenty-five EP modifiers were identified (three enhancers and 22 suppressors), none of which correspond to previously known components of Chk2 signaling. Three EPs caused defects in G2 arrest after irradiation with incomplete penetrance when homozygous, and are likely directly involved in the response to DNA damage. Possible roles for these modifiers in the DNA damage response and Chk2 signaling are discussed.

• Molecules and Cells
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• 제45권11호
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• pp.792-805
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• 2022

Repairing damaged DNA and removing all physical connections between sister chromosomes is important to ensure proper chromosomal segregation by contributing to chromosomal stability. Here, we show that the depletion of non-SMC condensin I complex subunit H (NCAPH) exacerbates chromosome segregation errors and cytokinesis failure owing to sister-chromatid intertwinement, which is distinct from the ultra-fine DNA bridges induced by DNA inter-strand crosslinks (DNA-ICLs). Importantly, we identified an interaction between NCAPH and GEN1 in the chromatin involving binding at the N-terminus of NCAPH. DNA-ICL activation, using ICL-inducing agents, increased the expression and interaction between NCAPH and GEN1 in the soluble nuclear and chromatin, indicating that the NCAPH-GEN1 interaction participates in repairing DNA damage. Moreover, NCAPH stabilizes GEN1 within chromatin at the G2/M-phase and is associated with DNA-ICL-induced damage repair. Therefore, NCAPH resolves DNA-ICL-induced ultra-fine DNA bridges by stabilizing GEN1 and ensures proper chromosome separation and chromosome structural stability.

• 대한약학회:학술대회논문집
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• 대한약학회 2000년도 NEW STRATEGY FOR DRUG DEVELOPMENT IN POST-GENOMIC ERA(대한약학회)
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• pp.55-56
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• 2000

• 전자공학회논문지SC
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• 제48권6호
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• pp.51-56
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• 2011

자성 산화철 나노입자(iron oxide nanoparticle, ${\gamma}-Fe_2O_3$) 표면을 기능성 유기 분자를 이용하여 아민기($-NH_2$), 카르복실기(-COOH)로 표면 처리 하였으며, 이들 기능기로 표면 처리된 산화철 나노입자를 FT-IR을 이용하여 나노입자 표면을 분석하였다. 아민기, 카르복실기로 표면처리된 산화철 나노입자 표면에 특정 배열을 갖는 21-base pair 길이의 프로브 DNA를 고정하였고, 형광 라벨(Cy5)이 부착된 상보적, 비상보적 타게트 DNA를 이용하여 고정된 프로브 DNA와 hybridization을 진행하였다. 각각의 상보적, 비상보적 타게트 DNA와 hybridization 처리한 산화철 나노입자를 confocal microscopy를 이용하여 관찰하였으며, 그 결과 산화철 나노입자를 이용하여 특정 배열의 DNA검출에 성공하였다.

• 센서학회지
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• 제21권5호
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• pp.359-366
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• 2012

Nanopore DNA sequencing is an emerging and promising technique that can potentially realize the goal of a low-cost and high-throughput method for analyzing human genome. Especially, solid-state nanopores have relatively high mechanical stability, simple surface modification, and facile fabrication process without the need for labeling or amplification of PCR (polymerized chain reaction) in DNA sequencing. For these advantages of solid-sate nanopores, the use of solid-state nanopores has been extensively considered for developing a next generation DNA sequencing technology. Solid-state nanopore sequencing technique can determine and count charged molecules such as single-stranded DNA, double-stranded DNA, or RNA when they are driven to pass through a membrane nanopore between two electrolytes of cis-trans chambers with applied bias voltage by measuring the ionic current which varies due to the existence of the charged particles in the nanopore. Recently, many researchers have suggested that nanopore-based sensors can be competitive with other third-generation DNA sequencing technologies, and may be able to rapidly and reliably sequence the human genome for under $1,000.

• Molecules and Cells
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• 제27권2호
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• pp.205-209
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• 2009

The loci of the 5S and 45S rRNA genes were localized on chromosomes in five species of Capsicum, namely, annuum, chacoense, frutescens, baccatum, and chinense by FISH. The 5S rDNA was localized to the distal region of one chromosome in all species observed. The number of 45S rDNA loci varied among species; one in annuum, two in chacoense and frutescens, and chinense, and four in baccatum, with the exceptions that 'CM334' of annuum had three loci and 'tabasco' of frutescens gad one locus. 'CM334'-derived BAC clones, 384B09 and 365P05, were screened with 5S rDNA as a probe, and BACs 278M03 and 262A23 were screened with 25S rDNA as a probe. Both ends of these BAC clones were sequenced. FISH with these BAC probes on pachytenes from 'CM334' plant showed one 5S rDNA locus and three 45S rDNA loci, consistent with the patterns on the somatic chromosomes. The 5S rDNA probe was also applied on extended DNA fibers to reveal that its coverage measured as long as 0.439 Mb in the pepper genome. FISH techniques applied on somatic and meiotic chromosomes and fibers have been established for chili to provide valuable information about the copy number variation of 45S rDNA and the actual physical size of the 5S rDNA in chili.

• The Plant Pathology Journal
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• 제18권4호
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• pp.187-191
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• 2002

This paper describes the cloning and sequence analysis of the 5'-terminal region and full-length cDNA production of genomic RNA of Lily symptomless virus (LSV), a Species Of the genus Carlavirus. A sing1e DNA band about 600 bp harboring the 5'-end of genomic RNA of the virus was successfully amplified by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE), and was cloned for nucleotide sequence determination. Sequence analysis of selected RACE cDNA clones revealed that the LSV 5'non-translated region consists of 67 nucleotides long of AT rich stretch followed GC rich from the 5'-end. To produce full-length cDNA products for the viral genomic RNA, a set of LSV-specific primers could be designed based on the obtained sequence in this study and the known sequences of 3'-terminal region for the virus. Full-length cDNA copies of LSV, an 8.4 kb long, were directly amplified by the long-template RT-PCR technique from the purified viral genomic RNA samples. This full-length cDNA copies were analyzed by restriction mapping. The molecules produced in this study can be useful for the production of in vitro infectious cDNA clone, as well as, for the completion of genomic RNA sequence and genome structure for the virus.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2004년도 춘계학술대회 학술발표 논문집 제14권 제1호
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• pp.97-100
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• 2004

The identification of the DNA structure as a double-stranded helix consting of two nucleotide chain molecules was a milestone in modern molecular biology. The DNA chip technology is based on reverse hybridization that follows the principle of complementary binding of double-stranded DNA. DNA chip can be described as the deposition of defined nucleic acid sequences, probes, on a solid substrate to form a regular array of elements that are available for hybridization to complementary nucleic acids, targets. DNA chips based on cDNA clons, oligonucleotides and genomic clons have been developed for gene expression studies, genetic variation analysis and genomic changes associated with disease including cancers and genetic diseases. DNA chips for gene expression profiling can be used for functional analysis in human eel Is and animal models, disease-related gene studies, assessment of gene therapy, assessment of genetically modified food, and research for drug discovery. DNA chips for genetic variation detection can be used for the detection of mutations or chromosomal abnormalities in cnacers, drug resistances in cancer cells or pathogenic microbes, histocompatibility analysis for transplantation, individual identification for forensic medicine, and detection and discrimination of pathogenic microbes. The DNA chip will be generalized as a useful tool in clinical diagnostics in near future. Lab-on-a chip and informatics will facilitate the development of a variety of DNA chips for diagnostic purpose.

• Molecules and Cells
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• 제25권4호
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• pp.457-461
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• 2008

DNA damage checkpoint is an important self-defense mechanism for the maintenance of genome stability. Defects in DNA damage signaling and repair lead to various disorders and increase tumor incidence in humans. In the past 10 years, we have identified many components involved in the DNA damage-signaling pathway, including the product of breast cancer susceptibility gene 1 (BRCA1). Mutations in BRCA1 are associated with increased risk of breast and ovarian cancers, highlighting the importance of this DNA damage-signaling pathway in tumor suppression. While it becomes clear that BRCA1 plays a crucial role in the DNA damage responsive pathway, exactly how BRCA1 receives DNA damage signals and exerts its checkpoint function has not been fully addressed. A series of recent studies reported the discovery of many novel components involved in DNA damage-signaling pathway. These newly identified checkpoint proteins, including RNF8, RAP80 and CCDC98, work in concern in recruiting BRCA1 to DNA damage sites and thus regulate BRCA1 function in G2/M checkpoint control. This review will summarize these recent findings and provide an updated view of the regulation of BRCA1 in response to DNA damage.