Name: real-time tracking of dna fragment separation by smartphone
Uploaded: 2017-06-01T15:00:00.000+00:00
Duration: 6 min 58 s
Description: Watch this Scientific Journal Video about Real-time Tracking of DNA Fragment Separation by Smartphone at JoVE.com

우리는 중국 국립 자연 과학 재단 (No 21205078)과 중국 고등 교육 박사 과정 프로그램 (No.20123120110002)의 지원에 감사드립니다. 이 연구는 중국의 국가 핵심 연구 및 개발 프로그램 (2016YFB1102303), 중국의 국가 기본 연구 프로그램 (973 프로그램 2015CB352001) 및 중국 자연 과학 재단 (61378060)에 의해 부분적으로 지원되었습니다.

1. SGE 칩의 기본 설계 <ol><li> 폴리 메틸 메타 크릴 레이트 (PMMA) 또는 폴리 카보네이트와 같은 투명 플라스틱을 사용하십시오. 참고 : SGE 칩은 그림 1B 에 나와 있습니다. SGE 칩은 TBE 버퍼 용 원통형 구멍, DNA 분리 용 채널 및 전극 용 구멍을 따라 삽입 된 2 개의 차선으로 구성됩니다. </li><li> 레이저 조각기를 사용하여 PMMA 블록에서 SGE 채널 어레이를 제작하십시오. 참고 : 칩의 기하학적 매개 변수는 분리 할 DNA의 크기에 따라 다릅니다. 예를 들어, DNA 조각이 1,000bp보다 작 으면 SGE 칩의 최적 채널 매개 변수는 2.5mm x 4.0mm x 90mm (폭 x 깊이 x 길이)입니다. </li><li> SGE 디자인을 기반으로 DNA 샘플을로드하기 위해 칩에 우물을 만들기 위해 빗을 제작하십시오. </li></ol> 2. 아가로 오스 겔의 제조 <ol><li> 10 × TBE (1 × TBE =89 mM 트리스, 89 mM 붕산 및 2 mM EDTA; pH 8.4) 및 증류수를 1:19 비율로 혼합 하였다. </li><li> 100-bp DNA 사다리를 분리하기위한 1.0 % 아가 로즈 겔을 준비한다. 참고 : 0.5x TBE 버퍼에서 아가로 오스의 농도는 분리 할 DNA 단편의 크기에 따라 다릅니다. </li><li> 플라스크에 0.1 g의 아가로 오스를 넣고 0.5 x TBE 완충액 10 mL를 넣는다. 참고 : 준비된 용액의 부피는 플라스크 용량의 1/3보다 적어야합니다. </li><li> 플라스크를 방부제 필름으로 밀봉 한 다음 전자 레인지 (중간, 1.0 분)에서 아가로 오스 / 버퍼 혼합물을 가열하십시오. 플라스크를 전자 렌지에 넣기 전에 방폭이 될 경우 방수 필름에 구멍을 뚫습니다. </li><li> SGE 칩의 4 채널에 녹인 아가로 오스 솔루션 2.7 ML을 부어. 우물을 만들기 위해 빗을 아가로 오스 용액에 넣으십시오. 참고 : 녹은 아가로 오스 솔루션은 실온에서 3 분 후 겔 상태로 냉각됩니다. </li><li> g에서 빗을 꺼냅니다.겔을 덮고 0.5x TBE 완충액 0.9 mL를 넣어 젤을 덮는다. </li></ol> 3. SGE 칩에서 전기 영동 실행하기 <ol><li> LED 광원을 켜고 광원 위에 425 ~ 505 nm 밴드 패스 필터를 놓습니다. </li><li> 100 bp DNA 사다리 14.4 μL와 SYBR Green 1.6 μL를 볼텍스를 사용하여 섞는다. </li><li> SGE 칩 ( 그림 2 )에서 아가로 오스 겔의 각 우물에 혼합물 4 μL를 적재하십시오. </li><li> SGE 칩의 두 차선에 전극을 놓습니다. </li><li> SGE 칩 위에 550 ~ 700 nm 밴드 패스 필터를 배치하십시오. </li><li> 전원을 켜십시오. 전기 전압을 180V (20V / cm)로 설정하십시오. 스마트 폰을 켜서 DNA 단편 분리 과정을 기록하십시오 ( 그림 3 ). </li><li> 10 분 후에 전기 영동이 끝나면 전원과 LED 표시등을 끕니다. </li><li> SGE 칩을 청소하십시오. </li></ol>

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이해 충돌이 선언되지 않습니다.

아가 로스 겔 전기 영동은 DNA, RNA 및 단백질 분리에 널리 사용됩니다. 이 연구는 전통적인 겔 전기 영동 프로토콜을 대체 할 새로운 방법을 제안합니다. 결과는 50, 100 및 1,000 bp DNA 사다리가 작은 조립 장치에서 잘 분리 될 수 있음을 보여줍니다. 이 방법의 가장 큰 장점은 거의 화학 물질을 소비하지 않고 핵산을 분리 할 수있을뿐만 아니라 분리 과정을 기록 할 수 있다는 것입니다. ...

<html> 슬랩 겔 전기 영동 (SGE)은 DNA 단편 분리 1 , 2 , 3 , 4 , 5 에 가장 효과적인 방법이며 따라서 생화학 및 생물학적 분석에서 다용도 도구로 간주됩니다 6 , 7 , 8 . 그러나 많은 실험에서 SGE가 다음 네 가지 문제에 의해 제한된다는 것을 나타냅니다. (1) 분리에는 수 시간이 걸리고 심지어 며칠이 걸립니다. (2) 화학 물질 소비가 매우 높다. (3) 복잡한 장치 ( 예 : 2D 전기 영동 세포, 전기 영동 전원 및 겔 이미징 시스템)가 필요합니다. (4) 겔 영상 시스템은 실험이 끝났을 때 분리 된 DNA 조각만을 관찰 할 수있다. 또한, SGE 9 에서 일반적으로 사용되는 ethidium bromide (EtBr)10 = 돌연변이 유발 및 암 유발 11,12 . 따라서 EtBr이 들어있는 젤을 나눠 줄 때는 항상 장갑을 착용해야합니다. 모세관 전기 영동 (CE)은 자동 작동, 짧은 분리 시간, 낮은 소비 등과 같은 SGE에 비해 13 , 14 , 15 , 16 , 17의 다양한 장점을 가지고 있습니다. 그러나 CE 장비는 꽤 비쌉니다. 따라서 이러한 한계를 극복하기 위해 DNA 분리를위한 시스템이 개발되었습니다 ( 그림 1 ). 이러한 시스템은 화학 물질 소비를 크게 줄이고 SGE 실험 시간 (8 분 미만)을 절약 할 수있을뿐만 아니라 스마트 폰을 통해 아가로 오스 겔에서 DNA 분리 과정을 실시간으로 추적 할 수도 있습니다. 이 프로토콜에 설명 된 절차를 따르면, 학생들은SGE 칩을 설계 및 제작하고, 칩에서 아가 로스 겔을 준비하고, 스마트 폰으로 간단한 SGE 시스템을 설치하고 아가로 오스 겔에서 DNA 이동 과정을 기록 할 수 있어야한다.

<table><tbody><tr><td>10&amp;times;TBE</td><td>Beijing Solarbio Science &amp;amp; Technology Co., Ltd.</td><td>T1051</td><td></td></tr><tr><td>50 bp DNA ladder</td><td>Takara Bio Inc.</td><td>3421A</td><td></td></tr><tr><td>100 bp DNA ladder</td><td>Takara Bio Inc.</td><td>3422A</td><td></td></tr><tr><td>1 kbp DNA ladder</td><td>Takara Bio Inc.</td><td>3426A</td><td></td></tr><tr><td>SYBR GREEN</td><td>Takara Bio Inc.</td><td>5760A</td><td></td></tr><tr><td>Agarose</td><td>Sigma-Aldrich Corporate</td><td>V900510</td><td></td></tr></tbody></table>

real-time tracking of dna fragment separation by smartphone

슬래브 겔 전기 영동 (SGE)은 DNA 단편을 분리하는 가장 일반적인 방법입니다. 따라서 그것은 생물학 및 다른 분야에 광범위하게 적용됩니다. 그러나 전통적인 SGE 프로토콜은 매우 지루하고 실험에 많은 시간이 걸립니다. 또한, SGE 실험에서 화학 물질 소비가 매우 높습니다. 이 연구는 SGE 칩을 기반으로 DNA 조각을 분리하는 간단한 방법을 제안한다. 이 칩은 조각 기계로 만든다. 두 개의 플라스틱 시트가 광 신호의 여기 및 방출 파장에 사용됩니다. DNA 밴드의 형광 신호는 스마트 폰으로 수집됩니다. 이 방법을 확인하기 위해 50, 100 및 1,000 bp DNA 사다리를 분리했습니다. 결과는 5,000 bp보다 작은 DNA 사다리가이 방법을 사용할 때 12 분 이내에 고해상도로 분석 할 수 있음을 보여 주며 전통적인 SGE 방법에 대한 이상적인 대체품임을 나타냅니다.

<html> 그림 4 , 그림 5 및 그림 6 은 50, 100 및 1,000 bp DNA 사다리의 겔 전기 영동 후 일반적인 결과를 나타냅니다. 실험 후, DNA 조각은 잘 분리되었다. 또한 동일한 샘플을 SGE 칩의 4 개 채널에서 분리하여 동일한 크기의 DNA 조각이 각 실험에서 동일한 거리로 이동 함을 보여줍니다. DNA 사다리의 분리 성능은 이동 거...

Watch this Scientific Journal Video about Real-time Tracking of DNA Fragment Separation by Smartphone at JoVE.com

Real-time Tracking of DNA Fragment Separation by Smartphone

Smartphone을 이용한 DNA 단편 분리 실시간 추적

전통적인 슬랩 젤 전기 영동 (SGE) 실험은 복잡한 장치와 높은 화학 물질 소비가 필요합니다. 이 연구는 단시간 내에 DNA 단편을 분리하는 저비용 방법을 설명하는 프로토콜을 제시합니다.

Slab gel electrophoresis (SGE) is the most common method for the separation of DNA fragments; thus, it is broadly applied to the field of biology and ...

real-time-tracking-of-dna-fragment-separation-by-smartphone

Research

JoVE Journal

Biochemistry

14.4K 조회수.  University of Shanghai for Science and Technology.  전통적인 슬랩 젤 전기 영동 (SGE) 실험은 복잡한 장치와 높은 화학 물질 소비가 필요합니다. 이 연구는 단시간 내에 DNA 단편을 분리하는 저비용 방법을 설명하는 프로토콜을 제시합니다. 

비디오: Real-time Tracking of DNA Fragment Separation by Smartphone

Detection of Copy Number Alterations Using Single Cell Sequencing

Detection of genomic changes at single cell resolution is important for characterizing genetic heterogeneity and evolution in normal tissues, cancers, and microbial populations. Traditional methods for assessing genetic heterogeneity have been limited by low resolution, low sensitivity, and/or low specificity. Single cell sequencing has emerged as a powerful tool for detecting genetic heterogeneity with high resolution, high sensitivity and, when appropriately analyzed, high specificity. Here we provide a protocol for the isolation, whole genome amplification, sequencing, and analysis of single cells. Our approach allows for the reliable identification of megabase-scale copy number variants in single cells. However, aspects of this protocol can also be applied to investigate other types of genetic alterations in single cells.

Single cell sequencing is an increasingly popular and accessible tool for addressing genomic changes at high resolution. We provide a protocol that uses single cell sequencing to identify copy number alterations in single cells.

단일 셀 시퀀싱을 사용하여 복사 번호 수선의 검출

Detection of genomic changes at single cell resolution is important for characterizing genetic heterogeneity and evolution in normal tissues, cancers, and ...

연구

유전학

Modified Terminal Restriction Fragment Analysis for Quantifying Telomere Length Using In-gel Hybridization

There are several different techniques for measuring telomere length, each with their own advantages and disadvantages. The traditional approach, Telomere Restriction Fragment (TRF) analysis, utilizes a DNA hybridization technique whereby genomic DNA samples are digested with restriction enzymes, leaving behind telomere DNA repeats and some sub-telomeric DNA. These are separated by agarose gel electrophoresis, transferred to a filter membrane and hybridized to oligonucleotide probes tagged with either chemiluminescence or radioactivity to visualize telomere restriction fragments. This approach, while requiring a larger quantity of DNA than other techniques such as PCR, can measure the telomere length distribution of a population of cells and allows measurement expressed in absolute kilobases. This manuscript demonstrates a modified DNA hybridization procedure for determining telomere length. Genomic DNA is first digested with restriction enzymes (that do not cut telomeres) and separated by agarose gel electrophoresis. The gel is then dried and the DNA is denatured and hybridized in situ to a radiolabeled oligonucleotide probe. This in situ hybridization avoids loss of telomere DNA and improves signal intensity. Following hybridization, the gels are imaged utilizing phosphor screens and the telomere length is quantified using a graphing program. This procedure was developed by the laboratories of Drs. Woodring Wright and Jerry Shay at the University of Texas Southwestern1,2. Here, we present a detailed description of this procedure, with some modifications.

In this article, a detailed protocol for quantifying telomere length using a modified terminal restriction fragment analysis is discussed that provides fast and efficient direct measurement of telomere length. This technique can be applied to a variety of cell sources of DNA for quantifying telomere length.

In-gel Hybridization을 이용한 Telomere 길이 정량을위한 수정 된 terminal restriction fragment 분석

There are several different techniques for measuring telomere length, each with their own advantages and disadvantages. The traditional approach, Telomere ...

암 연구학

A Simple, Robust, and High Throughput Single Molecule Flow Stretching Assay Implementation for Studying Transport of Molecules Along DNA

We describe a simple, robust and high throughput single molecule flow-stretching assay for studying 1D diffusion of molecules along DNA. In this assay, glass coverslips are functionalized in a one-step reaction with silane-PEG-biotin. Flow cells are constructed by sandwiching an adhesive tape with pre-cut channels between a functionalized coverslip and a PDMS slab containing inlet and outlet holes. Multiple channels are integrated into one flow cell and the flow of reagents into each channel can be fully automated, which significantly increases the assay throughput and reduces hands-on time per assay. Inside each channel, biotin-&#955;-DNAs are immobilized on the surface and a laminar flow is applied to flow-stretch the DNAs. The DNA molecules are stretched to &#62;80% of their contour length and serve as spatially extended templates for studying the binding and transport activity of fluorescently labeled molecules. The trajectories of single molecules are tracked by time-lapse Total Internal Reflection Fluorescence (TIRF) imaging. Raw images are analyzed using streamlined custom single particle tracking software to automatically identify trajectories of single molecules diffusing along DNA and estimate their 1D diffusion constants.

This protocol demonstrates a simple, robust and high throughput single molecule flow-stretching assay for studying one-dimensional (1D) diffusion of molecules along DNA.

간단 하 고 강력한, 높은 처리량 단일 분자 DNA에 따라 분자의 수송을 공부에 대 한 스트레칭 분석 결과 구현 흐름

We describe a simple, robust and high throughput single molecule flow-stretching assay for studying 1D diffusion of molecules along DNA. In this assay, ...

생화학

Real-time Observation of the DNA Strand Exchange Reaction Mediated by Rad51

The DNA strand exchange reaction mediated by Rad51 is a critical step of homologous recombination. In this reaction, Rad51 forms a nucleoprotein filament on single-stranded DNA (ssDNA) and captures double-stranded DNA (dsDNA) non-specifically to interrogate it for a homologous sequence. After encountering homology, Rad51 catalyzes DNA strand exchange to mediate pairing of the ssDNA with the complementary strand of the dsDNA. This reaction is highly regulated by numerous accessary proteins in vivo. Although conventional biochemical assays have been successfully employed to examine the role of such accessory protein in vitro, kinetic analysis of intermediate formation and its progression into a final product has proven challenging due to the unstable and transient nature of the reaction intermediates. To observe these reaction steps directly in solution, fluorescence resonance energy transfer (FRET)-based real-time observation systems of this reaction were established. Kinetic analysis of real-time observations shows that the DNA strand exchange reaction mediated by Rad51 obeys a three-step reaction model involving the formation of a three-strand DNA intermediate, maturation of this intermediate, and the release of ssDNA from the mature intermediate. The Swi5-Sfr1 complex, an accessary protein conserved in eukaryotes, strongly enhances the second and third steps of this reaction. The FRET-based assays presented here enable us to uncover the molecular mechanisms through which recombination accessary proteins stimulate the DNA strand exchange activity of Rad51. The primary goal of this protocol is to enhance the repertoire of techniques available to researchers in the field of homologous recombination, particularly those working with proteins from species other than Schizosaccharomyces pombe, so that the evolutionary conservation of the findings presented herein can be determined.

Fluorescence resonance energy transfer-based real-time observation systems of the DNA strand exchange reaction mediated by Rad51 were developed. Using the protocols presented here, we are able to detect the formation of reaction intermediates and their conversion into products, while also analyzing the enzymatic kinetics of the reaction.

중재 Rad51 DNA 물가 교환 반응의 실시간 관찰

The DNA strand exchange reaction mediated by Rad51 is a critical step of homologous recombination. In this reaction, Rad51 forms a nucleoprotein filament ...

Application of DNA Fingerprinting using the D1S80 Locus in Lab Classes

In biological sciences, DNA fingerprinting has been widely used for paternity testing, forensic applications and phylogenetic studies. Here, we describe a reliable and robust method for genotyping individuals by Variable Number of Tandem Repeat (VNTR) analysis in the context of undergraduate laboratory classes. The human D1S80 VNTR locus is used in this protocol as a highly polymorphic marker based on variation in the number of repetitive sequences.
This simple protocol conveys useful information for teachers and the implementation of DNA fingerprinting in practical laboratory classes. In the presented laboratory exercise, DNA extraction followed by PCR amplification is used to determine genetic variation at the D1S80 VNTR locus. Differences in the fragment size of PCR products are visualized by agarose gel electrophoresis. The fragment sizes and repeat numbers are calculated based on a linear regression of the size and migration distance of a DNA size standard.
Following this guide, students should be able to:
&#8226;&#160; Harvest and extract DNA from buccal mucosa epithelial cells 
&#8226;&#160; Perform a PCR experiment and understand the function of various reaction components 
&#8226;&#160; Analyze the amplicons by agarose gel electrophoresis and interpret the results 
&#8226;&#160; Understand the use of VNTRs in DNA fingerprinting and its application in biological sciences

Application of DNA Fingerprinting using the D1S80 Locus in Lab Classes

Here we describe a simple protocol to generate DNA fingerprinting profiles by amplifying the VNTR locus D1S80 from epithelial cell DNA.

실험실 클래스에서 D1S80 로커스를 사용하여 DNA 지문 응용 프로그램

In biological sciences, DNA fingerprinting has been widely used for paternity testing, forensic applications and phylogenetic studies. Here, we describe a ...

Single-Molecule Dwell-Time Analysis of Restriction Endonuclease-Mediated DNA Cleavage

This novel total internal reflection fluorescence microscopy-based assay facilitates the simultaneous measurement of the length of the catalytic cycle for hundreds of individual restriction endonuclease (REase) molecules in one experiment. This assay does not require protein labeling and can be carried out with a single imaging channel. In addition, the results of multiple individual experiments can be pooled to generate well-populated dwell-time distributions. Analysis of the resulting dwell-time distributions can help elucidate the DNA cleavage mechanism by revealing the presence of kinetic steps that cannot be directly observed. Example data collected using this assay with the well-studied REase, EcoRV - a dimeric Type IIP restriction endonuclease that cleaves the palindromic sequence GAT&#8595;ATC (where &#8595; is the cut site) - are in agreement with prior studies. These results suggest that there are at least three steps in the pathway to DNA cleavage that is initiated by introducing magnesium after EcoRV binds DNA in its absence, with an average rate of 0.17 s-1 for each step.

Using quantum-dot-labeled DNA and total internal reflection fluorescence microscopy, we can investigate the reaction mechanism of restriction endonucleases while using unlabeled protein. This single-molecule technique allows for massively multiplexed observation of individual protein-DNA interactions, and data can be pooled to generate well-populated dwell-time distributions.

Single-Molecule Dwell-Time Analysis of restriction Endonuclease-mediated DNA cleavage(제한 엔도뉴클레아제 매개 DNA 절단의 단일 분자 체류 시간 분석)

This novel total internal reflection fluorescence microscopy-based assay facilitates the simultaneous measurement of the length of the catalytic cycle for ...

Bradford Assay를 사용하여 단백질을 정량화하기 위한 분석 장치로서의 스마트폰

RGBradford: Protein Quantitation with a Smartphone Camera

Protein quantitation is an essential procedure in life sciences research. Amongst several other methods, the Bradford assay is one of the most used. Because of its widespread, the limitations and advantages of the Bradford assay have been exhaustively reported, including several modifications of the original method to improve its performance. One of the alterations of the original method is the use of a smartphone camera as an analytical instrument. Taking advantage of the three forms of the Coomassie Brilliant Blue dye that exist in the conditions of the Bradford assay, this paper describes how to accurately quantify protein in samples using color data extracted from a single picture of a microplate. After performing the assay in a microplate, a picture is taken using a smartphone camera, and RGB color data is extracted from the picture using a free and open-source image analysis software application. Then, the ratio of blue to green intensity (in the RGB scale) of samples with unknown concentrations of protein is used to calculate the protein content based on a standard curve. No significant difference is observed between values calculated using RGB color data and those calculated using conventional absorbance data.

저자 스포트라이트: 스마트폰을 사용한 Bradford Assay의 단백질 정량화에 대한 대안적 접근 방식 

This paper provides a protocol for protein quantification using the Bradford assay and a smartphone as an analytical device. Protein levels in samples can be quantified using color data extracted from a picture of a microplate taken with a smartphone.

RGBradford: 스마트폰 카메라를 이용한 단백질 정량 분석

Protein quantitation is an essential procedure in life sciences research. Amongst several other methods, the Bradford assay is one of the most used. ...

<meta charset="utf8"></head><body>ssDNA-RPA Tract Growth에서 관찰된 CMG 매개 DNA 풀기

Single-Molecule Real-Time Visualization of DNA Unwinding by CMG Helicase

Faithful genome duplication is essential for preserving the genetic stability of dividing cells. DNA replication is carried out during the S phase by a dynamic complex of proteins termed the replisome. At the heart of the replisome is the&#160;CDC45-MCM2-7-GINS (CMG) helicase, which separates the two strands of the DNA double helix such that DNA polymerases can copy each strand. During genome duplication, replisomes must overcome a plethora of obstacles and challenges. Each of these threatens genome stability, as failure to replicate DNA completely and accurately can lead to mutations, diseases, or cell death. Therefore, it is of great interest to understand how CMG functions in the replisome during both normal replication and replication stress. Here, we describe a total internal reflection fluorescence (TIRF) microscopy assay using recombinant purified proteins, which allows for real-time visualization of surface-tethered stretched DNA molecules by individual CMG complexes. This assay provides a powerful platform to investigate CMG behavior at the single-molecule level, allowing helicase dynamics to be directly observed with real-time control over reaction conditions.

<meta charset="utf8"></head><body>저자 스포트라이트: Unraveling the Dynamics of Eukaryotic DNA Replication Through Single-Molecule Visualization (단일 분자 시각화를 통한 진핵생물 DNA 복제의 역학 규명)

This protocol demonstrates performing a single-molecule assay for live visualization of DNA unwinding by CMG helicase. It describes (1) preparing a DNA substrate, (2) purifying fluorescently labeled Drosophila melanogaster CMG helicase, (3) preparing a microfluidic flow cell for total internal reflection fluorescence (TIRF) microscopy, and (4) the single-molecule DNA unwinding assay.

CMG Helicase를 이용한 DNA 풀림의 단일 분자 실시간 시각화

Faithful genome duplication is essential for preserving the genetic stability of dividing cells. DNA replication is carried out during the S phase by a ...

Smartphone을 이용한 DNA 단편 분리 실시간 추적

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단일 셀 시퀀싱을 사용하여 복사 번호 수선의 검출

In-gel Hybridization을 이용한 Telomere 길이 정량을위한 수정 된 terminal restriction fragment 분석

간단 하 고 강력한, 높은 처리량 단일 분자 DNA에 따라 분자의 수송을 공부에 대 한 스트레칭 분석 결과 구현 흐름

중재 Rad51 DNA 물가 교환 반응의 실시간 관찰

실험실 클래스에서 D1S80 로커스를 사용하여 DNA 지문 응용 프로그램

Single-Molecule Dwell-Time Analysis of restriction Endonuclease-mediated DNA cleavage(제한 엔도뉴클레아제 매개 DNA 절단의 단일 분자 체류 시간 분석)

RGBradford: 스마트폰 카메라를 이용한 단백질 정량 분석

RGBradford: 스마트폰 카메라를 이용한 단백질 정량 분석

RGBradford: 스마트폰 카메라를 이용한 단백질 정량 분석

CMG Helicase를 이용한 DNA 풀림의 단일 분자 실시간 시각화