• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
• /
• pp.711-712
• /
• 2000

DNA probe assay comprising a microwell as' solid matrix for the immobilization of streptavidin (SA) and an oligonucleotide with covalently bound fluorecein as detection probe was developed. The insolubilized SA captured the biotinylated DNA product of polymerase chain reaction (PCR), and the product was denatured under a basic condition. The remaining single-stranded DNA on the solid surface was hybridized with the probe for signal generation that was performed based on enzyme-linked immuno -reactions.

• BMB Reports
• /
• 제35권2호
• /
• pp.194-198
• /
• 2002

Eukaryotic replication protein A (RPA) is a single-stranded(ss) DNA binding protein with multiple functions in DNA replication, repair, and genetic recombination. The 70-kDa subunit of eukaryotic RPA contains a conserved four cysteine-type zinc-finger motif that has been implicated in the regulation of DNA replication and repair. Recently, we described a novel function for the zinc-finger motif in the regulation of human RPA's ssDNA binding activity through reduction-oxidation (redox). Here, we show that yeast RPA's ssDNA binding activity is regulated by redox potential through its RPA32 and/or RPA14 subunits. Yeast RPA requires a reducing agent, such as dithiothreitol (DTT), for its ssDNA binding activity. Also, under non-reducing conditions, its DNA binding activity decreases 20 fold. In contrast, the RPA 70 subunit does not require DTT for its DNA binding activity and is not affected by the redox condition. These results suggest that all three subunits are required for the regulation of RPA's DNA binding activity through redox potential.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2007년도 제38회 하계학술대회
• /
• pp.1375-1376
• /
• 2007

A synthesized 21-mer single-stranded DNA(ss DNA) was covalently immobilized onto a self-assembled aminoethanethiol monolayer modified gold electrode onto QCM. The covalently immobilized ssDNA was hybridized with complementary ssDNA. The interaction between surface immobilized ssDNA and complementary 21-mer DNA in solution was also examined. Each step was followed by monitoring changes in the QCM frequency with time. Also, PBS with pH 7.0 was selected as a supporting electrolyte in order to get maximum sensitivity and good bioactivity.

• Bulletin of the Korean Chemical Society
• /
• 제27권11호
• /
• pp.1731-1732
• /
• 2006

• 생명과학회지
• /
• 제19권3호
• /
• pp.305-310
• /
• 2009

플라스미드 pGKV21에는 229-nt single-strand DNA initiation (ssi) signal이 존재한다. Asymmetric PCR 기법으로 합성된 229-nt ssDNA 단편을 이용하여 실제로 RNA polymerase에 의한 priming ability와 protein interaction을 확인하였다. in vitro primer RNA 합성 실험 결과, 229-nt ssDNA 단편은 filamentous M13 phage의 주형 DNA에서와 비슷한 효율로 시발체 RNA를 합성하였으며, 이 반응은 strand-specific하게 이루어졌다. DNase I footprinting과 gel retardation 실험 결과, RNA polymerase와 SSB 단백질은 229-nt ssDNA 단편에 stable interaction을 하며, 시발체 RNA를 합성하였다. 또한, in vivo 조건 하에서 RNA polymerase의 저해제인 rifampicin을 처리하여 세포내에 ssDNA 중간체가 집적되는 정도를 비교하여 본 결과, 플라스미드 pGKV21은 rifampicin-sensitive RNA polymerase가 상보가닥 합성에 관여 함을 보여 주었다.

• 전자공학회논문지SC
• /
• 제48권2호
• /
• pp.86-90
• /
• 2011

전계효과 트랜지스터(FETs)를 이용한 전하 검출형 DNA센서는 DNA가 가지고 있는 음전하를 중성화 시키는 양이온의 영향은 매우 중요하다. 본 논문에서는 양이온 농도에 의존하는 Debye length에 관한 연구를 통해 DNA 검출감도를 평가하였다. Debye length는 낮은 농도의 NaCl 용액에서 긴 거리를 유지하며, Debye length가 높은 용액에서 DNA가 가지고 있은 음전하는 게이트 채널에 보다 많은 영향을 미친다. 용액내 NaCl농도가 1 mM인 버퍼 용액에서 상보적 DNA의 hybridization에 의한 전계효과 트랜지스터의 게이전압은 21 mV 시프트 했으며, NaCl 농도가 10 mM인 버퍼 용액에서는 7.2 mV, NaCl농도가 100 mM인 버퍼 용액에서는 전계효과 트랜지스터의 게이트 전압이 5.1 mV 각각 시프트 하였다. 이러한 결과를 바탕으로 전계효과 트랜지스터를 이용한 전하 검출형 DNA센서의 검출 감도는 Debye length에 의존하는 것을 규명하였다.

• 생명과학회지
• /
• 제8권2호
• /
• pp.119-125
• /
• 1998

dsRNA결합인자인 RBF단백질을 정제하여 이의 단일 또는 이중선의 RNA 또는 DNA 와의 결합도를 측정하였다ㅓ. RBF단백질은 이들과 각각 반응시켜 그 결합도는 SDS-PAGE에 의하여 비교관찰하였다. RBF단백질은 dsRNA와은 강한 결합력을 나타낸 반면 기타의 핵산구조에 대해서는 이러한 결과를 나타내지 못하였다. 인산화 실험의 결과, RBF단백질은 poly(I) : poly(C)의 존재하에서 사람 도는 쥐 모두로 부터의 PKR 효소의 자가인산화를 유사한 방식으로 억제하였다. 이는 다른 종류의 진핵세포생물에서 단백질합성조절을 위한 PKR과 RBF가 유사한 경쟁적 관련성을 유지하면서 존재함을 시사하고 있다.

• 한국식물학회:학술대회논문집
• /
• 한국식물학회 1987년도 식물생명공학 심포지움 논문집 Proceedings of Symposia on Plant Biotechnology
• /
• pp.149-155
• /
• 1987

Growth and development of a higher plant, or any living organism for that matter, could be defined as an orderly expression of the genome in time and space in close interaction with the environment. During differentiation and development of a tissue or organ a group of genes must be selectively turned on or turned off mainly by trans-acting regulators. In this general concept of regulation of regulation of gene expression, a DNA molecule is recognized at a specific nucleotide sequence by DNA-binding factors. Molecular biology of the regulatory factors such as hormones, and their receptors, target DNA sequences and DNA-binding proteins are well advanced. What is not clearly understood is the molecular basis of the interactions between DNA and binding factors, expecially of the usages of the dyad symmetry of the target DNA sequences and the dimeric nature of the DNA-binding proteins. A unique 3-dimensional structure of DNA has been proposed that may play an important role in the orderly expression of the gene. A foldback intercoil (FBI) DNA configuration which was originally found by electron microscopy among mtDNA molecules from pearl millet has some unique features. The FBI configuration of DNA is believed to be formed when a flexible double helix folds back and interwines in the widened major grooves resulting in a four stranded, intercoil DNA whose thickness is the same as that of double stranded DNA. More recently, the FBI structure of DNA has been also induced in vitro by a novel enzyme which was purified from pearl millet mitochondria. It has been proposed that the FBI DNA could be utillized in intramolecular recombination which leads to inversion or deletion, and in intermolecular recombination which can lead to either site-specific recombination, genetic recombination via single strand invasion, or cross strand recombination. The structure and function of DNA in 3-dimensional aspect is emphasized for better understanding orderly expression of genes during growth and development.

• BMB Reports
• /
• 제28권6호
• /
• pp.484-489
• /
• 1995

The product of bacteriophage T7 gene 2.5 is a single-stranded DNA binding protein and plays an important role in T7 DNA replication, recombination, and repair. Genetic analysis of T7 phage defective in gene 2.5 shows that the gene 2.5 protein is essential for T7 DNA replication and growth (Kim and Richardson, 1993). The C-terminal truncated gene 2.5 protein ($GP2.5-{\Delta}21C$) cannot substitute for wild-type gene 2.5 protein in vivo; suggesting that the C-terminal domain of gene 2.5 protein is essential for protein-protein interactions (Kim and Richardson, 1994; J. Biol. Chem. 269, 5070-5078). Truncated gene 2.5 proteins lacking 19 residues ($GP2.5-{\Delta}19N$) and 39 residues ($GP2.5-{\Delta}39N$) from the amino-terminal domain were constructed by in vitro mutagenesis. $GP2.5-{\Delta}19N$ can support the growth of T7 phage lacking gene 2.5 while $GP2.5-{\Delta}39N$ cannot substitute for wild-type gene 2.5 protein in vivo; however, its ability to bind to single-stranded DNA is not affected. These results clearly demonstrate that the 20~39 amino-terminal region of gene 2.5 protein is required for T7 growth in vivo but may not be involved in DNA binding activity.

• 대한전기학회논문지:전기물성ㆍ응용부문C
• /
• 제53권5호
• /
• pp.286-292
• /
• 2004

In this study, an integrated microelectrode array was fabricated on glass slide using microfabrication technology. Probe DNAs consisting of mercaptohexyl moiety at their 5-end were spotted on the gold electrode using micropipette or DNA arrayer utilizing the affinity between gold and sulfur. Cyclic voltammetry in 5mM ferricyanide/ferrocyanide solution at 100 ㎷/s confirmed the immobilization of probe DNA on the gold electrodes. When several DNAs were detected electrochemically, there was a difference between target DNA and control DNA in the anodic peak current values. It was derived from specific binding of Hoechst 33258 to the double stranded DNA due to hybridization of target DNA. It suggested that this DNA chip could recognize the sequence specific genes. It suggested that multichannel electrochemical DNA microarray is useful to develop a portable device for clinical gene diagnostic System.