이 작품은 과학 발전 (Cottrell 대학 학술 상 #22548)에 대 한 연구 corporation 및 TriLink 바이오 (ResearchReward 그랜트 #G139)에 의해 지원 되었다.

<ol>
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E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selection+of+2'-Fluoro-Modified+Aptamers+with+Optimized+Properties.">Selection of 2'-Fluoro-Modified Aptamers with Optimized Properties.</a> J Am Chem Soc. 139 (8), 2892-2895 (2017).</li><li>Taylor, A. I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Catalysts+from+synthetic+genetic+polymers.">Catalysts from synthetic genetic polymers.</a> Nature. 518 (7539), 427-430 (2015).</li><li>Alves Ferreira-Bravo, I., Cozens, C., Holliger, P., DeStefano, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selection+of+2'-deoxy-2'-fluoroarabinonucleotide+(FANA)+aptamers+that+bind+HIV-1+reverse+transcriptase+with+picomolar+affinity.">Selection of 2'-deoxy-2'-fluoroarabinonucleotide (FANA) aptamers that bind HIV-1 reverse transcriptase with picomolar affinity.</a> Nucleic Acids Res. 43 (20), 9587-9599 (2015).</li><li>Schultz, H. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Taq+DNA+Polymerase+Mutants+and+2'-Modified+Sugar+Recognition.">Taq DNA Polymerase Mutants and 2'-Modified Sugar Recognition.</a> Biochemistry. 54 (38), 5999-6008 (2015).</li><li>Rosenblum, S. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+and+discovery+of+new+combinations+of+mutant+DNA+polymerases+and+modified+DNA+substrates.">Design and discovery of new combinations of mutant DNA polymerases and modified DNA substrates.</a> Chembiochem. 18 (8), 816-823 (2017).</li><li>Creighton, S., Goodman, M. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gel+kinetic+analysis+of+DNA+polymerase+fidelity+in+the+presence+of+proofreading+using+bacteriophage+T4+DNA+polymerase.">Gel kinetic analysis of DNA polymerase fidelity in the presence of proofreading using bacteriophage T4 DNA polymerase.</a> J Biol Chem. 270 (9), 4759-4774 (1995).</li><li>Joyce, C. M., Benkovic, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=DNA+polymerase+fidelity:+kinetics,+structure,+and+checkpoints.">DNA polymerase fidelity: kinetics, structure, and checkpoints.</a> Biochemistry. 43 (45), 14317-14324 (2004).</li><li>Leconte, A. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Discovery,+characterization,+and+optimization+of+an+unnatural+base+pair+for+expansion+of+the+genetic+alphabet.">Discovery, characterization, and optimization of an unnatural base pair for expansion of the genetic alphabet.</a> J Am Chem Soc. 130 (7), 2336-2343 (2008).</li><li>Sanger, F., Nicklen, S., Coulson, A. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=DNA+sequencing+with+chain-terminating+inhibitors.">DNA sequencing with chain-terminating inhibitors.</a> Proc Natl Acad Sci U S A. 74 (12), 5463-5467 (1977).</li><li>Karger, B. L., Guttman, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=DNA+Sequencing+by+Capillary+Electrophoresis.">DNA Sequencing by Capillary Electrophoresis.</a> Electrophoresis. 30 (Suppl 1), S196-S202 (2009).</li><li>Lawyer, F. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-level+expression,+purification,+and+enzymatic+characterization+of+full-length+Thermus+aquaticus+DNA+polymerase+and+a+truncated+form+deficient+in+5'+to+3'+exonuclease+activity.">High-level expression, purification, and enzymatic characterization of full-length Thermus aquaticus DNA polymerase and a truncated form deficient in 5' to 3' exonuclease activity.</a> PCR Methods Appl. 2 (4), 275-287 (1993).</li><li>Lawyer, F. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation,+characterization,+and+expression+in+Escherichia+coli+of+the+DNA+polymerase+gene+from+Thermus+aquaticus.">Isolation, characterization, and expression in Escherichia coli of the DNA polymerase gene from Thermus aquaticus.</a> J Biol Chem. 264 (11), 6427-6437 (1989).</li><li>Carroll, S. S., Cowart, M., Benkovic, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+mutant+of+DNA+polymerase+I+(Klenow+fragment)+with+reduced+fidelity.">A mutant of DNA polymerase I (Klenow fragment) with reduced fidelity.</a> Biochemistry. 30 (3), 804-813 (1991).</li><li>Shendure, J., Ji, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Next-generation+DNA+sequencing.">Next-generation DNA sequencing.</a> Nat Biotechnol. 26 (10), 1135-1145 (2008).</li><li>Larsen, A. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+general+strategy+for+expanding+polymerase+function+by+droplet+microfluidics.">A general strategy for expanding polymerase function by droplet microfluidics.</a> Nat Commun. 7, 11235 (2016).</li><li>Cozens, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enzymatic+Synthesis+of+Nucleic+Acids+with+Defined+Regioisomeric+2'-5'+Linkages.">Enzymatic Synthesis of Nucleic Acids with Defined Regioisomeric 2'-5' Linkages.</a> Angew Chem Int Ed Engl. 54 (51), 15570-15573 (2015).</li></ol>

저자는 공개 없다.

여기, 우리는 M-DNA의 DNA 중 합 효소 중재 합성 특성 분석 결과 설명 했습니다. 근처-적외선 레이블이 DNA 뇌관을 사용 하 여 다르게 크기 oligonucleotides 해결 하려면 변성 polyacrylamide 젤 전기 이동 법을 사용 하 여 합성의 정확한 측정을 사용 oligonucleotides, 단일 뉴클레오티드 해상도 얻을 수 있습니다 우리. 이러한 접근 하거나 효소 (섹션 2.1)의 전반적인 활동을 측정 하거나 개별 단계 (다음 단계 2.1 참고...

DNA polymerases 정확 하 고 효율적인 DNA 합성을 수행 하 고 게놈 무결성을 유지 하기 위해 필수적입니다. 오류 없이 수백 초 당 뉴클레오티드를 합성 하는 능력 또한 분자 생물학 및 생명 공학에서 DNA polymerases 필수 도구를 만든다. 그러나, 이러한 속성은 또한 M-DNA 기판;에 대 한 응용 프로그램 제한 일반적으로 말하자면, 자연 DNA polymerases 수 없습니다 음성 합성 많은 잠재적으로 귀중 한 M-DNA 기판, 가능성이 인해 비표준 기판에 vivo에서를 사용 하 여에 대 한 높은 선택적 압력에. 많은 그룹 돌연변이 DNA polymerases M-DNA 합성1,2,3,,45;의 생성을 지시 진화 접근을 개발 했습니다. 이러한 노력은 DNA6,,78의 바이오 유틸리티를 확장 했습니다.
M-DNA 합성 돌연변이 DNA polymerases의 능력을 평가 하기 위해 우리9,10, 등11,,1213 일반적으로 사용 하는 DNA의 생체 외에서 측정 중 합 효소 활동이이 원고에 설명 되어 있습니다. 이 실험에서 DNA polymerases는 공동 incubated 레이블이 뇌관/템플릿을 이중와 nucleoside 3 인산 염 기판; 제품 젤 전기 이동 법에 의해 평가 됩니다. 특정 실험적인 질문, 돌연변이 DNA polymerases, 수정된 뇌관, 수정 된 서식 파일 또는 수정 된 nucleoside 된 사용할 수 있습니다, 활성화 돌연변이 효소 활동의 체계적인 생 화 확 적인 평가.
역사적으로, 이러한 분석 추적 DNA 합성; 5' 방사성 라벨에 의존 가장 일반적으로, P 32 33P 사용 되었습니다; 일반적으로, 라벨 이루어집니다 T4 polynucleotide 키 니 아 제11를 사용 하 여. 그러나, 유한 수명 및 방사성 레이블 및 그들의 안전한 처리의 상대적으로 높은 비용, 우리의 그룹은 합성 5' 근처-적외선 fluorophore DNA를 표시 대신 사용 합니다. 상대적으로 저렴 한 비용 근처-적외선 젤 영상을 사용 하 여, 우리는 비슷한 검출 한계가 방사성 레이블 (게시 되지 않은 결과)를 사용 하 여 이전 연구 관찰. 우리는 성공적으로 관측9, 과거 복제 하 고 우리가 하지 이전 측정된 속도 상수 (게시 되지 않은 결과)와 어떤 큰 양적 차이 관찰 했다.
DNA의 크기 및 따라서, DNA 종합의 정도 분석 하려면 우리는 생어 시퀀싱14 모 세관 전기 이동 법15의 도래 하기 전에 원래 개발 polyacrylamide 젤 전기 이동 법 방법에 의존. 분리 또는 거리; 분자량의 측정으로 사용할 수 있습니다. 대형, 수직 polyacrylamide 젤 단일 뉴클레오티드 해상도, 다양 한 길이의 DNA oligonucleotides의 양적 관찰 가능 얻을 수 있습니다.
샨 다, 이러한 실험은 중 합 효소 특성에 대 한 강력한 방법입니다. 시간으로 인해 민감한 반응, 준비 및 관리의 재현성 결과 얻을 필요가 있다. 또한, 아크릴 아 미드 젤은 DNA 합성, 수많은 다른 DNA 수정 반응, 단일 뉴클레오티드 해상도 측정 하는 매우 효과적인 방법 그것은 기술적으로 도전 수 것 이다. 잘하면 여기 프로토콜 가장 일반적인 실수를 피하고 있는 동안이 실험을 수행 하려면 사용자가 하면 수 있습니다.

<table>
	<tbody>
		<tr>
			<td>Tris HCl</td>
			<td>Promega</td>
			<td>H5123</td>
			<td></td>
		</tr>
		<tr>
			<td>Tris Base</td>
			<td>Promega</td>
			<td>H5131</td>
			<td></td>
		</tr>
		<tr>
			<td>MgCl2</td>
			<td>Fisher Scientific</td>
			<td>BP214-500</td>
			<td></td>
		</tr>
		<tr>
			<td>Acetylated BSA</td>
			<td>Promega</td>
			<td>PR-R3961</td>
			<td></td>
		</tr>
		<tr>
			<td>KCl</td>
			<td>Sigma</td>
			<td>P4504</td>
			<td></td>
		</tr>
		<tr>
			<td>Dithiothreitol (i.e. DTT)</td>
			<td>Research Products International</td>
			<td>D11000</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethylenediaminetetraacetic acid (i.e. EDTA) (0.5M solution)</td>
			<td>Sigma</td>
			<td>03690-100mL</td>
			<td></td>
		</tr>
		<tr>
			<td>Glycerol</td>
			<td>Sigma</td>
			<td>G5516</td>
			<td></td>
		</tr>
		<tr>
			<td>Formamide</td>
			<td>Acros</td>
			<td>AC42374-5000</td>
			<td></td>
		</tr>
		<tr>
			<td>Orange G</td>
			<td>Sigma Aldrich</td>
			<td>O3756</td>
			<td></td>
		</tr>
		<tr>
			<td>Bromophenol blue</td>
			<td>Fisher Scientific</td>
			<td>50-701-6973</td>
			<td></td>
		</tr>
		<tr>
			<td>dNTPs</td>
			<td>Fisher Scientific</td>
			<td>FERR0191</td>
			<td></td>
		</tr>
		<tr>
			<td>M-dNTPs (riboNTPs)</td>
			<td>Fisher Scientific</td>
			<td>45-001-341 (343, 345, 347)</td>
			<td></td>
		</tr>
		<tr>
			<td>M-dNTPs (all other modified NTPs)</td>
			<td>TriLink Biotechnologies</td>
			<td>assorted</td>
			<td></td>
		</tr>
		<tr>
			<td>primer 1</td>
			<td>IDT DNA / TriLink Biotechnologies</td>
			<td>Custom Syntheses</td>
			<td>We use the IR700 dye which can be purchased as a custom synthesis. We typically purchase the oligonucleotides HPLC purified. Sequence is 5&#8217;-dTAATACGACTCACTATAGGGAGA</td>
		</tr>
		<tr>
			<td>template 1</td>
			<td>IDT DNA / TriLink Biotechnologies</td>
			<td>Custom Syntheses</td>
			<td>We typically purchase the oligonucleotides HPLC purified. Sequence is 5&#8217;-dCGCTAGGACGGCATTGGATCAGTCTCCCTATAGTGAGTCGTATTA</td>
		</tr>
		<tr>
			<td>Acrylamide</td>
			<td>Research Products International</td>
			<td>A11405</td>
			<td>38.67% acrylamide and 1.33% bis-acrylamide</td>
		</tr>
		<tr>
			<td>Tris/Borate/EDTA (TBE) solid</td>
			<td>Research Products International</td>
			<td>T22020</td>
			<td></td>
		</tr>
		<tr>
			<td>Urea ultrapure</td>
			<td>Research Products International</td>
			<td>U20200</td>
			<td></td>
		</tr>
		<tr>
			<td>Gel tape</td>
			<td>CBS Scientific</td>
			<td>GT-72-10</td>
			<td></td>
		</tr>
		<tr>
			<td>Large white spring clamp polypropylene</td>
			<td>CBS Scientific</td>
			<td>GPC-0001</td>
			<td></td>
		</tr>
		<tr>
			<td>Ammonium persulfate (APS)</td>
			<td>Fisher Scientific</td>
			<td>BP179</td>
			<td></td>
		</tr>
		<tr>
			<td>Tetramethylethylenediamine (TEMED)</td>
			<td>Fisher Scientific</td>
			<td>BP15020</td>
			<td></td>
		</tr>
		<tr>
			<td>0.75 mm spacers</td>
			<td>CBS Scientific</td>
			<td>SGS-20-0740A</td>
			<td></td>
		</tr>
		<tr>
			<td>33x42 Notched Glass Plate Set</td>
			<td>CBS Scientific</td>
			<td>SGP33-040A</td>
			<td></td>
		</tr>
		<tr>
			<td>Wedge plate separator</td>
			<td>CBS Scientific</td>
			<td>WPS-100</td>
			<td></td>
		</tr>
		<tr>
			<td>Comb for gel electrophoresis</td>
			<td>CBS Scientific</td>
			<td>SG33-0734</td>
			<td></td>
		</tr>
		<tr>
			<td>Gel electrophoresis rig</td>
			<td>CBS Scientific</td>
			<td>SG-400-33</td>
			<td></td>
		</tr>
		<tr>
			<td>ultrapure water</td>
			<td></td>
			<td></td>
			<td>we use a Milli-Q system from Millipore</td>
		</tr>
		<tr>
			<td>DNA polymerases</td>
			<td></td>
			<td></td>
			<td>we prepare these in our laboratory using published protocols.</td>
		</tr>
	</tbody>
</table>

dna polymerase activity assay using near-infrared fluorescent labeled dna visualized by acrylamide gel electrophoresis

어떤 효소에 대 한 강력 하 고, 양적 메서드는 네이티브와 조작 효소의 특성에 대 한 필요. DNA polymerases에 대 한 DNA 합성 생체 외에서 DNA 종합 분석 결과 polyacrylamide 젤 전기 이동 법 뒤를 사용 하 여 특징 수 있습니다. 이 분석 결과의 목표 자연 DNA와 수정된 DNA (M-DNA)의 합성을 계량 하는 것입니다. 이러한 접근은 oligonucleotides 단일 뉴클레오티드 분해능, 효소 oligonucleotide 종합 동안 관찰의 개별 단계 사용을 해결 하는 데 특히 유용 합니다. 이러한 메서드는 생화학 및 생물 DNA 종합의 개별 단계, DNA 종합 그리고 DNA 바인딩 선호도의 오류율의 정상 속도 상수 측정 등 속성의 평가에 적용 되었습니다. 사용 하 여 구성 (NTP), M-DNA, 또는 돌연변이 DNA polymerases, 쌍을 효과적으로 평가 수 있는 기판-DNA 중 합 효소의 상대적 유틸리티 포함 하 되이 제한 되지 않고, 수정된 nucleoside 된 수정. 여기, 우리가 분석 결과 자체, 전례 없던 뇌관 DNA 라벨 근처-적외선 붙일 DNA 라는 등 전략에 맞게 만들 수 있어야 합니다 변경 내용을 포함 하 여 선발. 또한, 우리 쏟아져 아크릴 아 미드 젤에 대 한 중요 한 기술 단계 상세는 하 고 실행 하 고, 종종 수 있는 기술적으로 도전.

안정-상태 활동 (섹션 2.1, 그림 2의 결론에서 참고에서 설명)와 (섹션 2.1, 그림 1에 설명 된) 전체 활동의 질적 특성의 성공적인 polyacrylamide 젤 분석 표시 됩니다. 실패 polyacrylamide 젤 분석 (그림 3) 표시 됩니다.
참고 아무 상업적으로 사용할 수 있는 사다리 또는 ?...

Watch this Scientific Journal Video about DNA Polymerase Activity Assay Using Near-infrared Fluorescent Labeled DNA Visualized by Acrylamide Gel Electrophoresis at JoVE.com

DNA Polymerase Activity Assay Using Near-infrared Fluorescent Labeled DNA Visualized by Acrylamide Gel Electrophoresis

근 적외선 형광 레이블이 DNA 아크릴 아 미드 젤 전기 이동 법으로 시각을 사용 하 여 DNA 중 합 효소 활동 분석 결과

이 프로토콜의 근처-적외선 붙일 레이블된 DNA 젤 전기 이동 법 젤 이미지를 사용 하 여 변경 내용 관찰을 통해 수정 된 DNA의 DNA 중 합 효소 합성의 특성을 설명 합니다. 아크릴 아 미드 젤의 크기에 따라 다른 속도로 이동 하는 짧은 핵 산 분리의 고해상도 이미징에 사용 됩니다.

For any enzyme, robust, quantitative methods are required for characterization of both native and engineered enzymes. For DNA polymerases, DNA synthesis ...

dna-polymerase-activity-assay-using-near-infrared-fluorescent-labeled

Research

JoVE Journal

Biochemistry

14.0K 조회수.  W.M. Keck Science Department of Claremont Mckenna, Pitzer, and Scripps College. 이 프로토콜의 근처-적외선 붙일 레이블된 DNA 젤 전기 이동 법 젤 이미지를 사용 하 여 변경 내용 관찰을 통해 수정 된 DNA의 DNA 중 합 효소 합성의 특성을 설명 합니다. 아크릴 아 미드 젤의 크기에 따라 다른 속도로 이동 하는 짧은 핵 산 분리의 고해상도 이미징에 사용 됩니다.

비디오: DNA Polymerase Activity Assay Using Near-infrared Fluorescent Labeled DNA Visualized by Acrylamide Gel Electrophoresis

Characterization of Multi-subunit Protein Complexes of Human MxA Using Non-denaturing Polyacrylamide Gel-electrophoresis

The formation of oligomeric complexes is a crucial prerequisite for the proper structure and function of many proteins. The interferon-induced antiviral effector protein MxA exerts a broad antiviral activity against many viruses. MxA is a dynamin-like GTPase and has the capacity to form oligomeric structures of higher order. However, whether oligomerization of MxA is required for its antiviral activity is an issue of debate. We describe here a simple protocol to assess the oligomeric state of endogenously or ectopically expressed MxA in the cytoplasmic fraction of human cell lines by non-denaturing polyacrylamide gel electrophoresis (PAGE) in combination with Western blot analysis. A critical step of the protocol is the choice of detergents to prevent aggregation and/or precipitation of proteins particularly associated with cellular membranes such as MxA, without interfering with its enzymatic activity. Another crucial aspect of the protocol is the irreversible protection of the free thiol groups of cysteine residues by iodoacetamide to prevent artificial interactions of the protein. This protocol is suitable for a simple assessment of the oligomeric state of MxA and furthermore allows a direct correlation of the antiviral activity of MxA interface mutants with their respective oligomeric states.

This article describes a simple and rapid protocol to evaluate the oligomeric state of the dynamin-like GTPase MxA protein from lysates of human cells using a combination of non-denaturing PAGE with western blot analysis.

비 변성 폴리 아크릴 아미드 젤 전기 영동을 사용하여 인간의 MXA의 멀티 서브 유닛 단백질 복합체의 특성

The formation of oligomeric complexes is a crucial prerequisite for the proper structure and function of many proteins. The interferon-induced antiviral ...

연구

생화학

An Optimized Protocol for Electrophoretic Mobility Shift Assay Using Infrared Fluorescent Dye-labeled Oligonucleotides

Electrophoretic Mobility Shift Assays (EMSA) are an instrumental tool to characterize the interactions between proteins and their target DNA sequences. Radioactivity has been the predominant method of DNA labeling in EMSAs. However, recent advances in fluorescent dyes and scanning methods have prompted the use of fluorescent tagging of DNA as an alternative to radioactivity for the advantages of easy handling, saving time, reducing cost, and improving safety. We have recently used fluorescent EMSA (fEMSA) to successfully address an important biological question. Our fEMSA analysis provides mechanistic insight into the effect of a missense mutation, G73E, in the highly conserved HMG transcription factor SOX-2 on olfactory neuron type diversification. We found that mutant SOX-2G73E protein alters specific DNA binding activity, thereby causing olfactory neuron identity transformation. Here, we present an optimized and cost-effective step-by-step protocol for fEMSA using infrared fluorescent dye-labeled oligonucleotides containing the LIM-4/SOX-2 adjacent target sites and purified SOX-2 proteins (WT and mutant SOX-2G73E proteins) as a biological example.

We describe here an optimized protocol of fluorescent Electrophoretic Mobility Shift Assays (fEMSA) using purified SOX-2 proteins together with infrared fluorescent dye-labeled DNA probes as a case study to tackle an important biological question.

적외선 형광 염료로 표지 올리고 뉴클레오티드를 사용하여 전기 영동 이동성 시프트 분석을위한 최적화 된 프로토콜

Electrophoretic Mobility Shift Assays (EMSA) are an instrumental tool to characterize the interactions between proteins and their target DNA sequences. ...

Real-time Tracking of DNA Fragment Separation by Smartphone

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 others. However, the traditional SGE protocol is quite tedious, and the experiment takes a long time. Moreover, the chemical consumption in SGE experiments is very high. This work proposes a simple method for the separation of DNA fragments based on an SGE chip. The chip is made by an engraving machine. Two plastic sheets are used for the excitation and emission wavelengths of the optical signal. The fluorescence signal of the DNA bands is collected by smartphone. To validate this method, 50, 100, and 1,000 bp DNA ladders were separated. The results demonstrate that a DNA ladder smaller than 5,000 bp can be resolved within 12 min and with high resolution when using this method, indicating that it is an ideal substitute for the traditional SGE method.

Traditional slab gel electrophoresis (SGE) experiments require a complicated apparatus and high chemical consumption. This work presents a protocol that describes a low-cost method to separate DNA fragments within a short timeframe.

Smartphone을 이용한 DNA 단편 분리 실시간 추적

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 ...

Horizontal Gel Electrophoresis for Enhanced Detection of Protein-RNA Complexes

Native polyacrylamide gel electrophoresis is a fundamental tool of molecular biology that has been used extensively for the biochemical analysis of RNA-protein interactions. These interactions have been traditionally analyzed with polyacrylamide gels generated between two glass plates and samples electrophoresed vertically. However, polyacrylamide gels cast in trays and electrophoresed horizontally offers several advantages. For example, horizontal gels used to analyze complexes between fluorescent RNA substrates and specific proteins can be imaged multiple times as electrophoresis progresses. This provides the unique opportunity to monitor RNA-protein complexes at several points during the experiment. In addition, horizontal gel electrophoresis makes it possible to analyze many samples in parallel. This can greatly facilitate time course experiments as well as analyzing multiple reactions simultaneously to compare different components and conditions. Here we provide a detailed protocol for generating and using horizontal native gel electrophoresis for analyzing RNA-Protein interactions.

Native polyacrylamide gel electrophoresis is a fundamental tool for analyzing RNA-protein interactions. Traditionally most experiments have used vertical gels. However, horizontal gels provide several advantages, such as the opportunity to monitor complexes during electrophoresis. We provide a detailed protocol for generating and using horizontal native gel electrophoresis.

단백질 -RNA 복합체의 향상된 검출을위한 수평 겔 전기 영동

Native polyacrylamide gel electrophoresis is a fundamental tool of molecular biology that has been used extensively for the biochemical analysis of ...

Analysis of AtHIRD11 Intrinsic Disorder and Binding Towards Metal Ions by Capillary Gel Electrophoresis and Affinity Capillary Electrophoresis

Plants are strongly dependent on their environment. In order to adjust to stressful changes (e.g., drought and high salinity), higher plants evolve classes of intrinsically disordered proteins (IDPs) to reduce oxidative and osmotic stress. This article uses a combination of capillary gel electrophoresis (CGE) and mobility shift affinity electrophoresis (ACE) in order to describe the binding behavior of different conformers of the IDP AtHIRD11 from Arabidopsis thaliana. CGE is used to confirm the purity of AtHIRD11 and to exclude fragments, posttranslational modifications, and other impurities as reasons for complex peak patterns. In this part of the experiment, the different sample components are separated by a viscous gel inside a capillary by their different masses and detected with a diode array detector. Afterward, the binding behavior of the sample towards various metal ions is investigated by ACE. In this case, the ligand is added to the buffer solution and the shift in migration time is measured in order to determine whether a binding event has occurred or not. One of the advantages of using the combination of CGE and ACE to determine the binding behavior of an IDP is the possibility to automate the gel electrophoresis and the binding assay. Furthermore, CGE shows a lower limit of detection than the classical gel electrophoresis and ACE is able to determine the manner of binding a ligand in a fast manner. In addition, ACE can also be applied to other charged species than metal ions. However, the use of this method for binding experiments is limited in its ability to determine the number of binding sites. Nevertheless, the combination of CGE and ACE can be adapted for characterizing the binding behavior of any protein sample towards numerous charged ligands.

This protocol combines the characterization of a protein sample by capillary gel electrophoresis and a fast-binding screening for charged ligands by affinity capillary electrophoresis. It is recommended for proteins with a flexible structure, such as intrinsically disordered proteins, to determine any differences in binding for different conformers.

AtHIRD11 내장 장애 및 모 세관 젤 전기 이동 법 및 선호도 모 세관 전기 이동 법에 의해 금속 이온으로 바인딩 분석

Plants are strongly dependent on their environment. In order to adjust to stressful changes (e.g., drought and high salinity), higher plants evolve ...

Proofreading and DNA Repair Assay Using Single Nucleotide Extension and MALDI-TOF Mass Spectrometry Analysis

The maintenance of the genome and its faithful replication is paramount for conserving genetic information. To assess high fidelity replication, we have developed a simple non-labeled and non-radio-isotopic method using a matrix-assisted laser desorption ionization with time-of-flight (MALDI-TOF) mass spectrometry (MS) analysis for a proofreading study. Here, a DNA polymerase [e.g., the Klenow fragment (KF) of Escherichia coli DNA polymerase I (pol I) in this study] in the presence of all four dideoxyribonucleotide triphosphates is used to process a mismatched primer-template duplex. The mismatched primer is then proofread/extended and subjected to MALDI-TOF MS. The products are distinguished by the mass change of the primer down to single nucleotide variations. Importantly, a proofreading can also be determined for internal single mismatches, albeit at different efficiencies. Mismatches located at 2-4-nucleotides (nt) from the 3' end were efficiently proofread by pol I, and a mismatch at 5 nt from the primer terminus showed only a partial correction. No proofreading occurred for internal mismatches located at 6 - 9 nt from the primer 3' end. This method can also be applied to DNA repair assays (e.g., assessing a base-lesion repair of substrates for the endo V repair pathway). Primers containing 3' penultimate deoxyinosine (dI) lesions could be corrected by pol I. Indeed, penultimate T-I, G-I, and A-I substrates had their last 2 dI-containing nucleotides excised by pol I before adding a correct ddN 5'-monophosphate (ddNMP) while penultimate C-I mismatches were tolerated by pol I, allowing the primer to be extended without repair, demonstrating the sensitivity and resolution of the MS assay to measure DNA repair.

A non-labeled, non-radio-isotopic method for DNA polymerase proofreading and a DNA repair assay was developed by using high-resolution MALDI-TOF mass spectrometry and a single nucleotide extension strategy. The assay proved to be very specific, simple, rapid, and easy to perform for proofreading and repair patches shorter than 9-nucleotides.

교정 및 DNA 복구 분석 결과 단일 뉴클레오티드 확장 및 TOF MALDI 질량 분석 분석을 사용 하 여

The maintenance of the genome and its faithful replication is paramount for conserving genetic information. To assess high fidelity replication, we have ...

Analysis of Thylakoid Membrane Protein Complexes by Blue Native Gel Electrophoresis

Photosynthetic electron transfer chain (ETC) converts solar energy to chemical energy in the form of NADPH and ATP. Four large protein complexes embedded in the thylakoid membrane harvest solar energy to drive electrons from water to NADP+ via two photosystems, and use the created proton gradient for production of ATP. Photosystem PSII, PSI, cytochrome b6f (Cyt b6f) and ATPase are all multiprotein complexes with distinct orientation and dynamics in the thylakoid membrane. Valuable information about the composition and interactions of the protein complexes in the thylakoid membrane can be obtained by solubilizing the complexes from the membrane integrity by mild detergents followed by native gel electrophoretic separation of the complexes. Blue native polyacrylamide gel electrophoresis (BN-PAGE) is an analytical method used for the separation of protein complexes in their native and functional form. The method can be used for protein complex purification for more detailed structural analysis, but it also provides a tool to dissect the dynamic interactions between the protein complexes. The method was developed for the analysis of mitochondrial respiratory protein complexes, but has since been optimized and improved for the dissection of the thylakoid protein complexes. Here, we provide a detailed up-to-date protocol for analysis of labile photosynthetic protein complexes and their interactions in Arabidopsis thaliana.

A protocol for the elucidation of plant thylakoid protein complex organization and composition with blue native polyacrylamide gel electrophoresis (BN-PAGE) and 2D-SDS-PAGE is described. The protocol is optimized for Arabidopsis thaliana, but can be used for other plant species with minor modifications.

블루 기본 젤 전기 이동 법에 의해 Thylakoid 막 단백질 복합물의 분석

Photosynthetic electron transfer chain (ETC) converts solar energy to chemical energy in the form of NADPH and ATP. Four large protein complexes embedded ...

High Sensitivity Measurement of Transcription Factor-DNA Binding Affinities by Competitive Titration Using Fluorescence Microscopy

Accurate quantification of transcription factor (TF)-DNA interactions is essential for understanding the regulation of gene expression. Since existing approaches suffer from significant limitations, we have developed a new method for determining TF-DNA binding affinities with high sensitivity on a large scale. The assay relies on the established fluorescence anisotropy (FA) principle but introduces important technical improvements. First, we measure a full FA competitive titration curve in a single well by incorporating TF and a fluorescently labeled reference DNA in a porous agarose gel matrix. Unlabeled DNA oligomer is loaded on the top as a competitor and, through diffusion, forms a spatio-temporal gradient. The resulting FA gradient is then read out using a customized epifluorescence microscope setup. This improved setup greatly increases the sensitivity of FA signal detection, allowing both weak and strong binding to be reliably quantified, even for molecules of similar molecular weights. In this fashion, we can measure one titration curve per well of a multi-well plate, and through a fitting procedure, we can extract both the absolute dissociation constant (KD) and active protein concentration. By testing all single-point mutation variants of a given consensus binding sequence, we can survey the entire binding specificity landscape of a TF, typically on a single plate. The resulting position weight matrices (PWMs) outperform those derived from other methods in predicting in vivo TF occupancy. Here, we present a detailed guide for implementing HiP-FA on a conventional automated fluorescent microscope and the data analysis pipeline.

Here we present a novel method for determining binding affinities at equilibrium and in solution with high sensitivity on a large scale. This improves the quantitative analysis of transcription factor-DNA binding. The method is based on automated fluorescence anisotropy measurements in a controlled delivery system.

경쟁 적정 형광 현미경 검사 법을 사용 하 여 녹음 방송 요인 DNA 바인딩 선호도의 높은 감도 측정

Accurate quantification of transcription factor (TF)-DNA interactions is essential for understanding the regulation of gene expression. Since existing ...

DNA Electrophoresis Using Thiazole Orange Instead of Ethidium Bromide or Alternative Dyes

DNA gel electrophoresis using agarose is a common tool in molecular biology laboratories, allowing separation of DNA fragments by size. After separation, DNA is visualized by staining. This article demonstrates how to use thiazole orange to stain DNA. Thiazole orange compares favorably to common staining methods, in that it is sensitive, inexpensive, excitable with UV or blue light (to prevent sample damage), and safer than ethidium bromide. Labs already equipped to run DNA electrophoresis experiments using ethidium bromide can generally switch dyes with no additional changes to existing protocols, using UV light for detection. Blue-light detection to avoid sample damage can additionally be achieved with a blue-light source and emission filter. Labs already equipped for blue-light detection can simply switch dyes with no additional changes to existing protocols.

Here, we present a protocol to use thiazole orange for the detection of DNA in gel electrophoresis experiments. The use of thiazole orange allows elimination of ethidium bromide, and fluorescence detection can be achieved with either UV or blue light.

Ethidium 평범한 사람 또는 대체 염료 대신 Thiazole 오렌지를 사용 하 여 DNA 전기 이동 법

DNA gel electrophoresis using agarose is a common tool in molecular biology laboratories, allowing separation of DNA fragments by size. After separation, ...

DNA Sequence Recognition by DNA Primase Using High-Throughput Primase Profiling

DNA primase synthesizes short RNA primers that initiate DNA synthesis of Okazaki fragments on the lagging strand by DNA polymerase during DNA replication. The binding of prokaryotic DnaG-like primases to DNA occurs at a specific trinucleotide recognition sequence. It is a pivotal step in the formation of Okazaki fragments. Conventional biochemical tools that are used to determine the DNA recognition sequence of DNA primase provide only limited information. Using a high-throughput microarray-based binding assay and consecutive biochemical analyses, it has been shown that 1) the specific binding context (flanking sequences of the recognition site) influences the binding strength of the DNA primase to its template DNA, and 2) stronger binding of primase to the DNA yields longer RNA primers, indicating higher processivity of the enzyme. This method combines PBM and primase activity assay and is designated as high-throughput primase profiling (HTPP), and it allows characterization of specific sequence recognition by DNA primase in unprecedented time and scalability.&#160;

Protein binding microarray (PBM) experiments combined with biochemical assays link the binding and catalytic properties of DNA primase, an enzyme that synthesizes RNA primers on template DNA. This method, designated as high-throughput primase profiling (HTPP), can be used to reveal DNA-binding patterns of a variety of enzymes.

고처리량 프리마제 프로파일링을 사용하여 DNA 프리마제에 의한 DNA 서열 인식

DNA primase synthesizes short RNA primers that initiate DNA synthesis of Okazaki fragments on the lagging strand by DNA polymerase during DNA replication. ...