이 연구는 공군 과학 연구실의 LRIR 16RH3003J 보조금과 미국 국방부 연구 및 공학 차관실의 ARAP (Synthetic Biology for Military Environments Applied Research for the Advancement of S & T Priorities) 프로그램의 지원을 받았습니다.
ThyRS에 대한 플라스미드 벡터 서열(pSALv-RS-GFPa1, 3.4kb)은 J. Gallivan 박사에 의해 아낌없이 제공되었습니다. Bombyx mori 의 누에 고치는 매사추세츠주 터프츠 대학교의 D.L. Kaplan 박사가 아낌없이 기증했습니다.

<ol>
	<li>Slomovic, S., Pardee, K., Collins, 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=Synthetic+biology+devices+for+in+vitro+and+in+vivo+diagnostics.">Synthetic biology devices for in vitro and in vivo diagnostics.</a> Proceedings of the National Academy of Sciences of the United States of America. 112 (47), 14429-14435 (2015).</li><li>Harbaugh, S. V., Goodson, M. S., Dillon, K., Zabarnick, S., Kelley-Loughnane, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Riboswitch-based+reversible+dual-color+sensor.">Riboswitch-based reversible dual-color sensor.</a> ACS Synthetic Biology. 6 (5), 766-781 (2017).</li><li>K&#246;nig, H., Frank, D., Heil, R., Coenen, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthetic+genomics+and+synthetic+biology+applications+between+hopes+and+concerns.">Synthetic genomics and synthetic biology applications between hopes and concerns.</a> Current Genomics. 14 (1), 11-24 (2013).</li><li>Silverman, A. D., Karim, A. S., Jewett, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell-free+gene+expression:+An+expanded+repertoire+of+applications.">Cell-free gene expression: An expanded repertoire of applications.</a> Nature Reviews Genetics. 21, 151-170 (2020).</li><li>Chushak, Y., 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=Characterization+of+synthetic+riboswitch+in+cell-free+protein+expression+systems.">Characterization of synthetic riboswitch in cell-free protein expression systems.</a> RNA Biology. , 1-12 (2021).</li><li>Cole, S. D., 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=Quantification+of+interlaboratory+cell-free+protein+synthesis+variability.">Quantification of interlaboratory cell-free protein synthesis variability.</a> ACS Synthetic Biology. 8 (9), 2080-2091 (2019).</li><li>Thavarajah, W., 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=Point-of-use+detection+of+environmental+fluoride+via+a+cell-free+riboswitch-based+biosensor.">Point-of-use detection of environmental fluoride via a cell-free riboswitch-based biosensor.</a> ACS Synthetic Biology. 9 (1), 10-18 (2020).</li><li>Gr&#1235;we, A., 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+paper-based,+cell-free+biosensor+system+for+the+detection+of+heavy+metals+and+date+rape+drugs.">A paper-based, cell-free biosensor system for the detection of heavy metals and date rape drugs.</a> PLoS One. 14 (3), 0210940 (2019).</li><li>Lin, X., 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=Portable+environment-signal+detection+biosensors+with+cell-free+synthetic+biosystems.">Portable environment-signal detection biosensors with cell-free synthetic biosystems.</a> RSC Advances. 10 (64), 39261-39265 (2020).</li><li>Caschera, F., Lee, J. W., Ho, K. K. Y., Liu, A. P., Jewett, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell-free+compartmentalized+protein+synthesis+inside+double+emulsion+templated+liposomes+with+in+vitro+synthesized+and+assembled+ribosomes.">Cell-free compartmentalized protein synthesis inside double emulsion templated liposomes with in vitro synthesized and assembled ribosomes.</a> Chemical Communications. 52 (31), 5467-5469 (2016).</li><li>Niederholtmeyer, H., Chaggan, C., Devaraj, N. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Communication+and+quorum+sensing+in+non-living+mimics+of+eukaryotic+cells.">Communication and quorum sensing in non-living mimics of eukaryotic cells.</a> Nature Communications. 9, 5027 (2018).</li><li>Timin, A. S., Gould, D. J., Sukkhorukov, G. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multi-layer+microcapsules:+Fresh+insights+and+new+applications.">Multi-layer microcapsules: Fresh insights and new applications.</a> Expert Opinion on Drug Delivery. 14 (5), 583-587 (2017).</li><li>Bomati, E. K., Haley, J. E., Noel, J. P., Deheyn, D. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spectral+and+structural+comparison+between+bright+and+dim+green+fluorescent+proteins+in+Amphioxus.">Spectral and structural comparison between bright and dim green fluorescent proteins in Amphioxus.</a> Scientific Reports. 4, 5469 (2014).</li><li>Frey, B., Reischl, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amplification+of+Genomic+DNA+by+PCR.">Amplification of Genomic DNA by PCR.</a> Molecular Diagnosis of Infectious Diseases. Methods in Molecular Medicine. 13, 143-156 (1998).</li><li>Lee, P. Y., Costumbrado, J., Hsu, C. -. Y., Kim, Y. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Agarose+gel+electrophoresis+for+the+separation+of+DNA+fragments.">Agarose gel electrophoresis for the separation of DNA fragments.</a> Journal of Visualized Experiments. (62), e3923 (2012).</li><li>Zhou, Y., 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=Rapid+regeneration+and+reuse+of+silica+columns+from+PCR+purification+and+gel+extraction+kits.">Rapid regeneration and reuse of silica columns from PCR purification and gel extraction kits.</a> Scientific Reports. 8, 12870 (2018).</li><li>Kostylev, M., Otwell, A. E., Richardson, R. E., Suzuki, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cloning+should+be+simple:+Escherichia+coli+DH5&#945;-mediated+assembly+of+multiple+DNA+fragments+with+short+end+homologies.">Cloning should be simple: Escherichia coli DH5&#945;-mediated assembly of multiple DNA fragments with short end homologies.</a> PLoS One. 10 (9), 0137466 (2015).</li><li>Rockwood, D. N., 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=Materials+fabrication+from+Bombyx+mori+silk+fibroin.">Materials fabrication from Bombyx mori silk fibroin.</a> Nature Protocols. 6 (10), 1612-1631 (2011).</li><li>Drachuk, 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=Silk+macromolecules+with+amino+acid-Poly(Ethylene+Glycol)+grafts+for+controlling+layer-by-layer+encapsulation+and+aggregation+of+recombinant+bacterial+cells.">Silk macromolecules with amino acid-Poly(Ethylene Glycol) grafts for controlling layer-by-layer encapsulation and aggregation of recombinant bacterial cells.</a> ACS Nano. 9 (2), 1219-1235 (2015).</li><li>Antipov, A. A., Sukhorukov, G. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polyelectrolyte+multilayer+capsules+as+vehicles+with+tunable+permeability.">Polyelectrolyte multilayer capsules as vehicles with tunable permeability.</a> Advances in Colloid and Interface Science. 111 (1-2), 49-61 (2004).</li><li>Drachuk, I., Harbaugh, S., Ch&#225;vez, J. L., Kelley-Loughnane, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improving+the+activity+of+DNA-encoded+sensing+elements+through+confinement+in+silk+microcapsules.">Improving the activity of DNA-encoded sensing elements through confinement in silk microcapsules.</a> ACS Applied Materials &amp; Interfaces. 12 (43), 48329-48339 (2020).</li><li>Melnikov, S., Ben-Shem, A., Garreau de Loubresse, N., Jenner, L., Yusupova, G., Yusupov, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structural+basis+for+the+inhibition+of+the+eukaryotic+ribosome.">Structural basis for the inhibition of the eukaryotic ribosome.</a> Nature Structural &amp; Molecular Biology. 19 (6), 560-567 (2012).</li><li>Zhao, S., 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=The+future+of+layer-by-layer+assembly:+A+tribute+to+ACS+Nano+associate+editor+Helmuth+M&#246;hwald.">The future of layer-by-layer assembly: A tribute to ACS Nano associate editor Helmuth M&#246;hwald.</a> ACS Nano. 13 (6), 6151-6169 (2019).</li><li>Main, K. H. S., Provan, J. I., Haynes, P. J., Wells, G., Hartley, J. A., Pyne, A. L. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Atomic+force+microscopy-A+tool+for+structural+and+translational+DNA+research.">Atomic force microscopy-A tool for structural and translational DNA research.</a> APL Bioengineering. 5, 031504 (2021).</li><li>Riera, R., Feiner-Gracia, N., Fornaguera, C., Cascante, A., Borr&#243;s, S., Albertazzi, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tracking+the+DNA+complexation+state+of+pBAE+polyplexes+in+cells+with+super+resolution+microscopy.">Tracking the DNA complexation state of pBAE polyplexes in cells with super resolution microscopy.</a> Nanoscale. 11 (38), 17869-17877 (2019).</li><li>Bilokapic, S., Strauss, M., Halic, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cryo-EM+of+nucleosome+core+particle+interactions+in+trans.">Cryo-EM of nucleosome core particle interactions in trans.</a> Scientific Reports. 8, 7046 (2018).</li><li>Pritchard, E. M., Dennis, P. B., Omenetto, F., Naik, R. R., Kaplan, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physical+and+chemical+aspects+of+stabilization+of+compounds+in+silk.">Physical and chemical aspects of stabilization of compounds in silk.</a> Biopolymers. 97 (6), 479-498 (2012).</li><li>Fritz, B. R., Jamil, O. K., Jewett, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Implications+of+macromolecular+crowding+and+reducing+conditions+for+in+vitro+ribosome+construction.">Implications of macromolecular crowding and reducing conditions for in vitro ribosome construction.</a> Nucleic Acids Research. 43 (9), 4774-4784 (2015).</li><li>Ge, X., Luo, D., Xu, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell-free+protein+expression+under+macromolecular+crowding+conditions.">Cell-free protein expression under macromolecular crowding conditions.</a> PLoS One. 6 (12), 28707 (2011).</li><li>Cawte, A. D., Unrau, P. J., Rueda, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Live+cell+imaging+of+single+RNA+molecules+with+fluorogenic+mango+II+arrays.">Live cell imaging of single RNA molecules with fluorogenic mango II arrays.</a> Nature Communications. 11, 1283 (2020).</li><li>Chen, X., 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=Visualizing+RNA+dynamics+in+live+cells+with+bright+and+stable+fluorescent+RNAs.">Visualizing RNA dynamics in live cells with bright and stable fluorescent RNAs.</a> Nature Biotechnology. 37 (11), 1287-1293 (2019).</li></ol>

여기에 제시된 견해와 의견은 저자의 견해이며 반드시 DoD 또는 그 구성 요소의 견해를 나타내는 것은 아닙니다

다양한 유형의 DNA-인코딩된 센서 설계로 로딩된 선택적 투과성 하이드로겔 마이크로캡슐은 이 프로토콜에 따라 제조될 수 있다. LbL 접근법의 특징 중 하나는 상향식 조립 동안 마이크로 캡슐의 복잡성을 조정할 수 있다는 것인데, 이는 일반적으로 희생 템플릿에 분자 종의 흡착으로 시작됩니다. 초기 성분의 농도, pH 조건 및 층수를 조심스럽게 조절함으로써, 상이한 DNA 로딩 파라미터, 기능성 및 ?...

합성 생물학 분야는 미생물에 의해 진화된 자연적 메커니즘을 활용하여 환경과 잠재적 위협을 모니터링함으로써 감지 기능을 개발할 수 있는 독특한 기회를 제공합니다. 중요하게도, 이러한 감지 메커니즘은 일반적으로 이러한 미생물을 유해한 노출로부터 보호하고 유전자 발현을 조절하여 부정적인 영향을 완화하거나 독성 물질의 섭취를 방지하는 반응과 관련이 있습니다. 이러한 자연 반응을 활용하지만 새로운 표적을 인식하거나 정량화 목적으로 측정할 수 있는 측정 가능한 신호(일반적으로 형광)를 생성하도록 방향을 바꾸도록 전체 세포 센서를 만들기 위해 이러한 미생물을 설계하려는 상당한 노력이 있었습니다1,2. 현재, 유전자 변형 미생물(GMO)의 사용에 대한 우려, 특히 환경이나 인체에서 방출될 때, 전체 세포 또는 일부 유전 물질의 누출로 인해, 폴리머 매트릭스에 캡슐화되어 있더라도 이러한 감지 접근법을 활용하기 위한 대안적인 방법이 필요함을 시사한다3.
GMO 배포에 대한 걱정 없이 미생물 기반 감지의 이점을 활용하는 강력한 접근 방식은 체외 전사/번역(IVTT) 시스템을 사용하는 것입니다. 실용적인 관점에서 IVTT 시스템은 초음파 처리, 비드 박동 또는 기타를 포함한 다양한 수단으로 세포에서 "추출"된 활성 상태의 대부분의 세포 구성 요소를 포함하는 혼합물로 구성됩니다4. 이 공정의 최종 산물은 전사 및 번역을 수행하도록 이미 최적화된 생화학 반응 혼합물로, 전체 세포 사용과 관련된 제약 없이(막 확산, 형질전환 효율, 세포 독성 등) "개방형 용기" 형식으로 다양한 센서를 테스트하는 데 사용할 수 있습니다. 중요한 것은, 서로 다른 센서 구성 요소를 정량적으로 추가할 수 있고, 우리가 설명한 바와 같이 서로 다른 광학 및 분광 기술로 그 효과를 연구할 수 있다는것입니다 5. IVTT 시스템의 성능이 일관되지 않을 수 있음이 밝혀졌습니다. 그러나 최근 연구에서는 준비 및 특성화를 표준화하는 접근 방식을 보여주었으며, 이는 센서 설계6에서 성능을 연구할 때 큰 도움이 됩니다. 최근에, 중금속 이온, 약물, 정족수 감지 요소및 기타의 검출을 포함하여, 종이 매트릭스에서 그 성분들의 동결건조를 통해 종이-기반 분석법을 생성하기 위해 사용되는 IVTT 시스템의 많은 예들이 입증되었다 7,8,9. IVTT 기반 센서의 흥미로운 응용 분야는 토양, 물, 인체를 포함한 다양한 유형의 환경에서 감지 응용 분야에 사용된다는 것입니다. 이러한 IVTT 시스템을 이러한 까다로운 환경에 배포하려면 IVTT 구성 요소를 포함하고 성능 저하로부터 보호하기 위한 캡슐화 접근 방식을 구현해야 합니다.
IVTT 시스템에 대한 가장 일반적인 캡슐화 접근법은 지질 캡슐, 미셀, 폴리머솜 및 기타 밀접하게 밀폐된 마이크로컨테이너(10,11,12)의 사용을 포함한다. 이 접근 방식의 한 가지 단점은 외부 환경과의 통신을 허용하고 감지 기능을 제공하기 위해 컨테이너 안팎으로 재료를 운반하기 위해 수동 또는 능동 메커니즘을 통합해야 한다는 것입니다. 이러한 문제 중 일부를 극복하기 위해 이 연구에서는 IVTT 시스템에서 표현할 다양한 센서 설계에 대한 인코딩 재료를 캡슐화하는 간단하면서도 효과적인 접근 방식을 제공하는 방법을 보고합니다. 이 접근법은 관심 플라스미드의 존재 하에 바이오폴리머의 층별(LbL) 증착을 사용하여 높은 다공성을 가진 중공 마이크로캡슐을 생성함으로써 보호된 유전 물질이 선택한 IVTT의 다양한 구성 요소와 상호 작용할 수 있도록 합니다. 이 연구는 캡슐화된 플라스미드가 플라스미드 인코딩된 앱타머 및 해당 표적에 대한 리보스위치의 반응에서 볼 수 있듯이 이 고분자 매트릭스 내에서 활성화될 때 전사 및 번역을 지시할 수 있음을 입증했습니다. 또한 이 LbL 코팅은 특별한 보관 조건 없이 몇 달 동안 플라스미드를 보호합니다.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>(Z)-4-(3,5-difluoro-4-hydroxybenzylidene)-2-methyl-1-(2,2,2-trifluoroethyl)-1H-imidazol-5(4 H)-one (DFHBI-1T)</td>
			<td>Lucerna</td>
			<td>DFHBI-1T</td>
			<td></td>
		</tr>
		<tr>
			<td>5x T4 DNA Ligase Buffer</td>
			<td>ThermoFisher Scientific</td>
			<td>46300-018</td>
			<td></td>
		</tr>
		<tr>
			<td>6x Blue Gel Loading Dye</td>
			<td>New England BioLabs</td>
			<td>B7021S</td>
			<td></td>
		</tr>
		<tr>
			<td>96-well plates, black circular</td>
			<td>Corning</td>
			<td>3601</td>
			<td></td>
		</tr>
		<tr>
			<td>Agarose</td>
			<td>Sigma-Aldrich</td>
			<td>A9539</td>
			<td>BioReagent, for molecular biology, low EEO</td>
		</tr>
		<tr>
			<td>Ampicillin sodium salt</td>
			<td>Sigma-Aldrich</td>
			<td>A0166</td>
			<td>powder or crystals, BioReagent, suitable for cell culture</td>
		</tr>
		<tr>
			<td>BlpI restriction enzymes</td>
			<td>New England BioLabs</td>
			<td>R0585S</td>
			<td></td>
		</tr>
		<tr>
			<td>Corning Disposable Vacuum Filter/Storage Systems</td>
			<td>FisherScientific</td>
			<td>09-761-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Dimethyl sulfoxide, DMSO</td>
			<td>Sigma-Aldrich</td>
			<td>472301</td>
			<td>ACS reagent, &#8805;99.9%</td>
		</tr>
		<tr>
			<td>DNA Plasmid, pET28c-F30-2x Broccoli (5.4 kb), BrocApt.</td>
			<td>Addgene</td>
			<td>Plasmid #66788</td>
			<td></td>
		</tr>
		<tr>
			<td>DyLightTM550 Antibody Labeling kit (Invitrogen)</td>
			<td>ThermoFisher Scientific</td>
			<td>84530</td>
			<td></td>
		</tr>
		<tr>
			<td>E. coli S30 extract system for circular DNA</td>
			<td>Promega</td>
			<td>L1020</td>
			<td></td>
		</tr>
		<tr>
			<td>Falcon Conical centrifuge tubes, 15 mL</td>
			<td>FisherScientific</td>
			<td>14-959-53A</td>
			<td></td>
		</tr>
		<tr>
			<td>Falcon Conical centrifuge tubes, 50 mL</td>
			<td></td>
			<td>14-432-22</td>
			<td></td>
		</tr>
		<tr>
			<td>Fisherbrand Microcentrifuge tubes, 1.5 mL</td>
			<td>FisherScientific</td>
			<td>05-408-129</td>
			<td></td>
		</tr>
		<tr>
			<td>Hydrofluoric acid, HF</td>
			<td>Sigma-Aldrich</td>
			<td>695068</td>
			<td>ACS reagent, 48%</td>
		</tr>
		<tr>
			<td>Kanamycin sulfate</td>
			<td>Sigma-Aldrich</td>
			<td>60615</td>
			<td>mixture of Kanamycin A (main component) and Kanamycin B and C</td>
		</tr>
		<tr>
			<td>KpnI restriction enzymes</td>
			<td>New England BioLabs</td>
			<td>R0142S</td>
			<td></td>
		</tr>
		<tr>
			<td>LB agar plate supplemented with 100 &#181;g/mL ampicillin</td>
			<td>Sigma-Aldrich</td>
			<td>L5667</td>
			<td>pre-poured agar plates with 100 &#181;g/mL ampicillin</td>
		</tr>
		<tr>
			<td>LB agar plate supplemented with 50 &#181;g/mL kanamycin</td>
			<td>Sigma-Aldrich</td>
			<td>L0543</td>
			<td>pre-poured agar plates with 50 &#181;g/mL kanamycin</td>
		</tr>
		<tr>
			<td>LB broth (Lennox grade)</td>
			<td>Sigma-Aldrich</td>
			<td>L3022</td>
			<td></td>
		</tr>
		<tr>
			<td>Lithium bromide, LiBr</td>
			<td>Sigma-Aldrich</td>
			<td>213225</td>
			<td>ReagentPlus, &#8805;99%</td>
		</tr>
		<tr>
			<td>Max Efficiency DH5-&#945; competent E. coli strain</td>
			<td>ThermoFisher Scientific</td>
			<td>18258012</td>
			<td></td>
		</tr>
		<tr>
			<td>Methanol</td>
			<td>MilliporeSigma</td>
			<td>322415</td>
			<td>anhydrous, 99.8%</td>
		</tr>
		<tr>
			<td>MilliQ-water</td>
			<td>EMD MilliPore</td>
			<td></td>
			<td>Milli-Q Reference Water Purification System</td>
		</tr>
		<tr>
			<td>MinElute PCR Purification Kit</td>
			<td>Qiagen</td>
			<td>28004</td>
			<td></td>
		</tr>
		<tr>
			<td>N-(3-Dimethylaminopropyl)-N&#8242;-ethylcarbodiimide hydrochloride, EDC</td>
			<td>Sigma-Aldrich</td>
			<td>E1769</td>
			<td></td>
		</tr>
		<tr>
			<td>PBS (phosphate buffered saline)</td>
			<td>ThermoFisher Scientific</td>
			<td>10010023</td>
			<td>1x PBS, pH 7.4</td>
		</tr>
		<tr>
			<td>Phusion High-Fidelity DNA Polymerase</td>
			<td>New England Biolabs</td>
			<td>M0530S</td>
			<td></td>
		</tr>
		<tr>
			<td>Polyethylenimine, branched</td>
			<td>Sigma-Aldrich</td>
			<td>408727</td>
			<td>average Mw ~25,000</td>
		</tr>
		<tr>
			<td>PURExpress In Vitro Protein Synthesis Kit</td>
			<td>New England BioLabs</td>
			<td>E6800S</td>
			<td></td>
		</tr>
		<tr>
			<td>QIAEX II Gel Extraction Kit</td>
			<td>Qiagen</td>
			<td>20021</td>
			<td></td>
		</tr>
		<tr>
			<td>QIAprep Spin Miniprep Kit</td>
			<td>Qiagen</td>
			<td>&#160;27104</td>
			<td></td>
		</tr>
		<tr>
			<td>Quick-Load 2-Log DNA Ladder (0.1-10.0 kb)</td>
			<td>New England BioLabs</td>
			<td>N0469S</td>
			<td></td>
		</tr>
		<tr>
			<td>SiO&#8322; silica microspheres, 4.0 &#181;m</td>
			<td>Polysciences, Inc.</td>
			<td>24331-15</td>
			<td>10% aqueous solution</td>
		</tr>
		<tr>
			<td>Slide-A-Lyzer G2 Dialysis Cassettes, 3.5K MWCO, 15 mL</td>
			<td>ThermoFisher Scientific</td>
			<td>87724</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium carbonate, Na&#8322;CO&#8323;</td>
			<td>Sigma-Aldrich</td>
			<td>222321</td>
			<td>ACS reagent, anhydrous, &#8805;99.5%, powder</td>
		</tr>
		<tr>
			<td>Spectrum Spectra/Por Float-A-Lyzer G2 Dialysis Devices</td>
			<td>FisherScientific</td>
			<td>08-607-008</td>
			<td>Spectrum G235058</td>
		</tr>
		<tr>
			<td>SYBR Safe DNA gel stain</td>
			<td>ThermoFisher Scientific</td>
			<td>S33102</td>
			<td></td>
		</tr>
		<tr>
			<td>T4 DNA Ligase (5 U/&#181;L)</td>
			<td>ThermoFisher Scientific</td>
			<td>EL0011</td>
			<td></td>
		</tr>
		<tr>
			<td>Theophylline</td>
			<td>Sigma-Aldrich</td>
			<td>T1633</td>
			<td>anhydrous, &#8805;99%, powder</td>
		</tr>
		<tr>
			<td>Tris Acetate-EDTA buffer (TAE buffer)</td>
			<td>Sigma-Aldrich</td>
			<td>T6025</td>
			<td>Contains 40 mM Tris-acetate and 1 mM EDTA, pH 8.3.</td>
		</tr>
		<tr>
			<td>UltraPure DNase/RNase-Free Distilled Water</td>
			<td>FisherScientific</td>
			<td>10-977-023</td>
			<td></td>
		</tr>
		<tr>
			<td>ZymoPURE II Plasmid MaxiPrep kit</td>
			<td>ZymoResearch</td>
			<td>D4202</td>
			<td></td>
		</tr>
	</tbody>
</table>

preparation of multifunctional silk-based microcapsules loaded with dna plasmids encoding rna aptamers and riboswitches

우리는 희생 구형 코어에서 층별(LbL) 조립 방법을 통해 DNA가 함유된 실크 피브로인 마이크로캡슐을 제조하기 위한 프로토콜을 소개합니다. 프라임층 및 DNA 플라스미드의 흡착에 이어, 단일 실크층의 급성 탈수 동안 실크 2차 구조에서 β-시트를 유도함으로써 견고한 마이크로캡슐의 형성을 촉진하였다. 따라서 층상은 다중 수소 결합과 소수성 상호 작용을 통해 발생했습니다. 다층 쉘의 흡착 시, 코어-쉘 구조는 원격 감지 및/또는 표적 전달에 사용되는 금 나노입자(AuNP) 및/또는 항체(IgG)로 추가로 기능화될 수 있습니다. 폴리머 프라이머의 존재, DNA 및 실크 단백질의 농도, 다수의 흡착된 층과 같은 실리카 코어에 주요 거대분자를 순차적으로 증착하는 동안 몇 가지 주요 매개변수를 조정하면 다양한 투과성 및 DNA 로딩을 갖는 생체 적합성, DNA 함유 마이크로캡슐이 생성되었습니다. 실리카 코어의 용해 시, 프로토콜은 캡슐 멤브레인의 내부 표면에 고정된 DNA 플라스미드를 갖는 중공 및 견고한 마이크로캡슐의 형성을 입증하였다. DNA 플라스미드와 외부 환경 사이에 선택적으로 투과할 수 있는 생체적합성 막을 만들어 장기 보관 시 DNA를 보존하고 공간적으로 제한된 플라스미드의 출력 반응을 개선하는 데 중요한 역할을 했습니다. DNA 템플릿의 활성과 접근성은 시험관 내 전사 및 번역 반응(cell-free system) 동안 테스트되었습니다. RNA 라이트업 앱타머 및 리보스위치를 암호화하는 DNA 플라스미드는 쉘 막에서 형광 표지된 RNA 전사체 또는 GFPa1 단백질의 국소화 중에 시각화된 바와 같이 해당 분석물과 함께 성공적으로 활성화되었습니다.

여기에서 이 연구는 실크 단백질 캡슐에 캡슐화한 후 다양한 센서 디자인(두 가지 유형의 RNA 조절 전사/번역 요소)을 인코딩하는 DNA 템플릿의 기능을 다룹니다. 마이크로캡슐은 주요 구성 요소인 프라임층, 센서 설계를 인코딩하는 DNA 플라스미드 및 실크 피브로인 바이오폴리머의 템플릿화된 층별(LbL) 조립을 통해 제조되었습니다(그림 2). 층상 방식으로 거대분자를 증착하?...

Watch this Scientific Journal Video about Preparation of Multifunctional Silk-Based Microcapsules Loaded with DNA Plasmids Encoding RNA Aptamers and Riboswitches at JoVE.com

Preparation of Multifunctional Silk-Based Microcapsules Loaded with DNA Plasmids Encoding RNA Aptamers and Riboswitches

이 프로토콜은 여러 리간드를 추적할 수 있는 다중화된 시험관 내 바이오센서로서 견고하고 생체적합성 DNA가 함유된 마이크로캡슐의 형성을 설명합니다.

RNA 압타머 및 리보스위치를 인코딩하는 DNA 플라스미드가 로딩된 다기능 실크 기반 마이크로캡슐의 제조

We introduce a protocol for the preparation of DNA-laden silk fibroin microcapsules via the Layer-by-Layer (LbL) assembly method on sacrificial spherical ...

preparation-multifunctional-silk-based-microcapsules-loaded-with-dna

Research

JoVE Journal

Biology

1.3K 조회수.  UES Inc.. 이 프로토콜은 여러 리간드를 추적할 수 있는 다중화된 시험관 내 바이오센서로서 견고하고 생체적합성 DNA가 함유된 마이크로캡슐의 형성을 설명합니다.

비디오: Preparation of Multifunctional Silk-Based Microcapsules Loaded with DNA Plasmids Encoding RNA Aptamers and Riboswitches

Homemade Site Directed Mutagenesis of Whole Plasmids

Site directed mutagenesis of whole plasmids is a simple way to create slightly different variations of an original plasmid. With this method the cloned target gene can be altered by substitution, deletion or insertion of a few bases directly into a plasmid. It works by simply amplifying the whole plasmid, in a non PCR-based thermocycling reaction. During the reaction mutagenic primers, carrying the desired mutation, are integrated into the newly synthesized plasmid. In this video tutorial we demonstrate an easy and cost effective way to introduce base substitutions into a plasmid. The protocol works with standard reagents and is independent from commercial kits, which often are very expensive. Applying this protocol can reduce the total cost of a reaction to an eighth of what it costs using some of the commercial kits. In this video we also comment on critical steps during the process and give detailed instructions on how to design the mutagenic primers.

Site directed mutagenesis of whole plasmids is a simple way to create slightly different variations of an original plasmid. Here we demonstrate an easy and cost effective way to introduce base substitutions into a plasmid using standard reagents.

전체 Plasmids의 수제 사이트 감독 돌연변이 유발

Site directed mutagenesis of whole plasmids is a simple way to create slightly different variations of an original plasmid. With this method the cloned ...

연구

생물학

Visualizing Single-molecule DNA Replication with Fluorescence Microscopy

We describe a simple fluorescence microscopy-based real-time method for observing DNA replication at the single-molecule level. A circular, forked DNA template is attached to a functionalized glass coverslip and replicated extensively after introduction of replication proteins and nucleotides (Figure 1). The growing product double-strand DNA (dsDNA) is extended with laminar flow and visualized by using an intercalating dye. Measuring the position of the growing DNA end in real time allows precise determination of replication rate (Figure 2). Furthermore, the length of completed DNA products reports on the processivity of replication. This experiment can be performed very easily and rapidly and requires only a fluorescence microscope with a reasonably sensitive camera.


This protocol demonstrates a simple single-molecule fluorescence microscopy technique for visualizing DNA replication by individual replisomes in real time.

형광 현미경과 함께 머릿속으로 단일 분자의 DNA 복제

We describe a simple fluorescence microscopy-based real-time method for observing DNA replication at the single-molecule level. A circular, forked DNA ...

Generation of RNA/DNA Hybrids in Genomic DNA by Transformation using RNA-containing Oligonucleotides

Synthetic short nucleic acid polymers, oligonucleotides (oligos), are the most functional and widespread tools of molecular biology. Oligos can be produced to contain any desired DNA or RNA sequence and can be prepared to include a wide variety of base and sugar modifications. Moreover, oligos can be designed to mimic specific nucleic acid alterations and thus, can serve as important tools to investigate effects of DNA damage and mechanisms of repair. We found that Thermo Scientific Dharmacon RNA-containing oligos with a length between 50 and 80 nucleotides can be particularly suitable to study, in vivo, functions and consequences of chromosomal RNA/DNA hybrids and of ribonucleotides embedded into DNA. RNA/DNA hybrids can readily form during DNA replication, repair and transcription, however, very little is known about the stability of RNA/DNA hybrids in cells and to which extent these hybrids can affect the genetic integrity of cells. RNA-containing oligos, therefore, represent a perfect vector to introduce ribonucleotides into chromosomal DNA and generate RNA/DNA hybrids of chosen length and base composition. Here we present the protocol for the incorporation of ribonucleotides into the genome of the eukaryotic model system yeast /Saccharomyces cerevisiae/. Yet, our lab has utilized Thermo Scientific Dharmacon RNA-containing oligos to generate RNA/DNA hybrids at the chromosomal level in different cell systems, from bacteria to human cells.

This work shows how to form an RNA/DNA hybrid at the chromosomal level and reveal transfer of genetic information from RNA to genomic DNA in yeast cells.

RNA 함유 Oligonucleotides를 사용하여 변환하여 게놈 DNA에서 RNA / DNA 하이브리드의 생성

Synthetic short nucleic acid polymers, oligonucleotides (oligos), are the most functional and widespread tools of molecular biology. Oligos can be ...

iCLIP - Transcriptome-wide Mapping of Protein-RNA Interactions with Individual Nucleotide Resolution

The unique composition and spatial arrangement of RNA-binding proteins (RBPs) on a transcript guide the diverse aspects of post-transcriptional regulation1. Therefore, an essential step towards understanding transcript regulation at the molecular level is to gain positional information on the binding sites of RBPs2.
Protein-RNA interactions can be studied using biochemical methods, but these approaches do not address RNA binding in its native cellular context. Initial attempts to study protein-RNA complexes in their cellular environment employed affinity purification or immunoprecipitation combined with differential display or microarray analysis (RIP-CHIP)3-5. These approaches were prone to identifying indirect or non-physiological interactions6. In order to increase the specificity and positional resolution, a strategy referred to as CLIP (UV cross-linking and immunoprecipitation) was introduced7,8. CLIP combines UV cross-linking of proteins and RNA molecules with rigorous purification schemes including denaturing polyacrylamide gel electrophoresis. In combination with high-throughput sequencing technologies, CLIP has proven as a powerful tool to study protein-RNA interactions on a genome-wide scale (referred to as HITS-CLIP or CLIP-seq)9,10. Recently, PAR-CLIP was introduced that uses photoreactive ribonucleoside analogs for cross-linking11,12.
Despite the high specificity of the obtained data, CLIP experiments often generate cDNA libraries of limited sequence complexity. This is partly due to the restricted amount of co-purified RNA and the two inefficient RNA ligation reactions required for library preparation. In addition, primer extension assays indicated that many cDNAs truncate prematurely at the crosslinked nucleotide13. Such truncated cDNAs are lost during the standard CLIP library preparation protocol. We recently developed iCLIP (individual-nucleotide resolution CLIP), which captures the truncated cDNAs by replacing one of the inefficient intermolecular RNA ligation steps with a more efficient intramolecular cDNA circularization (Figure 1)14. Importantly, sequencing the truncated cDNAs provides insights into the position of the cross-link site at nucleotide resolution. We successfully applied iCLIP to study hnRNP C particle organization on a genome-wide scale and assess its role in splicing regulation14.

The spatial arrangement of RNA-binding proteins on a transcript is a key determinant of post-transcriptional regulation. Therefore, we developed individual-nucleotide resolution UV crosslinking and immunoprecipitation (iCLIP) that allows precise genome-wide mapping of the binding sites of an RNA-binding protein.

iCLIP - 개인 염기 해상도와 단백질 RNA 상호 작용의 Transcriptome 전체 매핑

The unique composition and spatial arrangement of RNA-binding proteins (RBPs) on a transcript guide the diverse aspects of post-transcriptional ...

In vitro Transcription and Capping of Gaussia Luciferase mRNA Followed by HeLa Cell Transfection

In vitro transcription is the synthesis of RNA transcripts by RNA polymerase from a linear DNA template containing the corresponding promoter sequence (T7, T3, SP6) and the gene to be transcribed (Figure 1A). A typical transcription reaction consists of the template DNA, RNA polymerase, ribonucleotide triphosphates, RNase inhibitor and buffer containing Mg2+ ions.
Large amounts of high quality RNA are often required for a variety of applications. Use of in vitro transcription has been reported for RNA structure and function studies such as splicing1, RNAi experiments in mammalian cells2, antisense RNA amplification by the "Eberwine method"3, microarray analysis4 and for RNA vaccine studies5. The technique can also be used for producing radiolabeled and dye labeled probes6. Warren, et al. recently reported reprogramming of human cells by transfection with in vitro transcribed capped RNA7. The T7 High Yield RNA Synthesis Kit from New England Biolabs has been designed to synthesize up to 180 &mu;g RNA per 20 &mu;l reaction. RNA of length up to 10kb has been successfully transcribed using this kit. Linearized plasmid DNA, PCR products and synthetic DNA oligonucleotides can be used as templates for transcription as long as they have the T7 promoter sequence upstream of the gene to be transcribed.
Addition of a 5' end cap structure to the RNA is an important process in eukaryotes. It is essential for RNA stability8, efficient translation9, nuclear transport10 and splicing11. The process involves addition of a 7-methylguanosine cap at the 5' triphosphate end of the RNA. RNA capping can be carried out post-transcriptionally using capping enzymes or co-transcriptionally using cap analogs. In the enzymatic method, the mRNA is capped using the Vaccinia virus capping enzyme12,13. The enzyme adds on a 7-methylguanosine cap at the 5' end of the RNA using GTP and S-adenosyl methionine as donors (cap 0 structure). Both methods yield functionally active capped RNA suitable for transfection or other applications14 such as generating viral genomic RNA for reverse-genetic systems15 and crystallographic studies of cap binding proteins such as eIF4E16.
In the method described below, the T7 High Yield RNA Synthesis Kit from NEB is used to synthesize capped and uncapped RNA transcripts of Gaussia luciferase (GLuc) and Cypridina luciferase (CLuc). A portion of the uncapped GLuc RNA is capped using the Vaccinia Capping System (NEB). A linearized plasmid containing the GLuc or CLuc gene and T7 promoter is used as the template DNA. The transcribed RNA is transfected into HeLa cells and cell culture supernatants are assayed for luciferase activity. Capped CLuc RNA is used as the internal control to normalize GLuc expression.

In vitro Transcription and Capping of Gaussia Luciferase mRNA Followed by HeLa Cell Transfection

This method describes high yield in vitro synthesis of both capped and uncapped mRNA from a linearized plasmid containing the Gaussia luciferase (GLuc) gene. The RNA is purified and a fraction of the uncapped RNA is enzymatically capped using the Vaccinia virus capping enzyme. In the final step, the mRNA is transfected into HeLa cells and cell culture supernatants are assayed for luciferase activity.

HELA 세포 Transfection 얹는 Gaussia의 루시페라제의 mRNA의 시험 관내 스크립트 작성 및 상한에

In vitro transcription is the synthesis of RNA transcripts by RNA polymerase from a linear DNA template containing the corresponding promoter sequence ...

Preparation of DNA-crosslinked Polyacrylamide Hydrogels

Mechanobiology is an emerging scientific area that addresses the critical role of physical cues in directing cell morphology and function. For example, the effect of tissue elasticity on cell function is a major area of mechanobiology research because tissue stiffness modulates with disease, development, and injury. Static tissue-mimicking materials, or materials that cannot alter stiffness once cells are plated, are predominately used to investigate the effects of tissue stiffness on cell functions. While information gathered from static studies is valuable, these studies are not indicative of the dynamic nature of the cellular microenvironment in vivo. To better address the effects of dynamic stiffness on cell function, we developed a DNA-crosslinked polyacrylamide hydrogel system (DNA gels). Unlike other dynamic substrates, DNA gels have the ability to decrease or increase in stiffness after fabrication without stimuli. DNA gels consist of DNA crosslinks that are polymerized into a polyacrylamide backbone. Adding and removing crosslinks via delivery of single-stranded DNA allows temporal, spatial, and reversible control of gel elasticity. We have shown in previous reports that dynamic modulation of DNA gel elasticity influences fibroblast and neuron behavior. In this report and video, we provide a schematic that describes the DNA gel crosslinking mechanisms and step-by-step instructions on the preparation DNA gels.

Our laboratory has developed DNA-crosslinked polyacrylamide hydrogels, a dynamic hydrogel system, to better understand the effects of modulating tissue stiffness on cell function. Here, we provide schematics, descriptions, and protocols to prepare these hydrogels.

DNA-가교 폴리 아크릴 아미드 하이드로 겔의 제조

Mechanobiology is an emerging scientific area that addresses the critical role of physical cues in directing cell morphology and function. For example, ...

Real-time Imaging of Single Engineered RNA Transcripts in Living Cells Using Ratiometric Bimolecular Beacons

The growing realization that both the temporal and spatial regulation of gene expression can have important consequences on cell function has led to the development of diverse techniques to visualize individual RNA transcripts in single living cells. One promising technique that has recently been described utilizes an oligonucleotide-based optical probe, ratiometric bimolecular beacon (RBMB), to detect RNA transcripts that were engineered to contain at least four tandem repeats of the RBMB target sequence in the 3&#8217;-untranslated region. RBMBs are specifically designed to emit a bright fluorescent signal upon hybridization to complementary RNA, but otherwise remain quenched. The use of a synthetic probe in this approach allows photostable, red-shifted, and highly emissive organic dyes to be used for imaging. Binding of multiple RBMBs to the engineered RNA transcripts results in discrete fluorescence spots when viewed under a wide-field fluorescent microscope. Consequently, the movement of individual RNA transcripts can be readily visualized in real-time by taking a time series of fluorescent images. Here we describe the preparation and purification of RBMBs, delivery into cells by microporation and live-cell imaging of single RNA transcripts.

Ratiometric bimolecular beacons (RBMBs) can be used to image single engineered RNA transcripts in living cells. Here, we describe the preparation and purification of RBMBs, delivery of RBMBs into cells by microporation and fluorescent imaging of single RNA transcripts in real-time.

비례 생체 분자 비콘을 사용하여 살아있는 세포의 단일 엔지니어링 RNA 성적 증명서의 실시간 영상

The growing realization that both the temporal and spatial regulation of gene expression can have important consequences on cell function has led to the ...

Reduced-gravity Environment Hardware Demonstrations of a Prototype Miniaturized Flow Cytometer and Companion Microfluidic Mixing Technology

Until recently, astronaut blood samples were collected in-flight, transported to earth on the Space Shuttle, and analyzed in terrestrial laboratories. If humans are to travel beyond low Earth orbit, a transition towards space-ready, point-of-care (POC) testing is required. Such testing needs to be comprehensive, easy to perform in a reduced-gravity environment, and unaffected by the stresses of launch and spaceflight. Countless POC devices have been developed to mimic laboratory scale counterparts, but most have narrow applications and few have demonstrable use in an in-flight, reduced-gravity environment. In fact, demonstrations of biomedical diagnostics in reduced gravity are limited altogether, making component choice and certain logistical challenges difficult to approach when seeking to test new technology. To help fill the void, we are presenting a modular method for the construction and operation of a prototype blood diagnostic device and its associated parabolic flight test rig that meet the standards for flight-testing onboard a parabolic flight, reduced-gravity aircraft. The method first focuses on rig assembly for in-flight, reduced-gravity testing of a flow cytometer and a companion microfluidic mixing chip. Components are adaptable to other designs and some custom components, such as a microvolume sample loader and the micromixer may be of particular interest. The method then shifts focus to flight preparation, by offering guidelines and suggestions to prepare for a successful flight test with regard to user training, development of a standard operating procedure (SOP), and other issues. Finally, in-flight experimental procedures specific to our demonstrations are described.

Spaceflight blood diagnostics need innovation. Few demonstrations have been published illustrating in-flight, reduced-gravity health diagnostic technology. Here we present a method for construction and operation of a parabolic flight test rig for a prototype point-of-care flow-cytometry design, with components and preparation strategies adaptable to other setups.

프로토 타입 소형 흐름 사이토와 동반자 미세 유체 혼합 기술의 감소 - 중력 환경 하드웨어 데모

Until recently, astronaut blood samples were collected in-flight, transported to earth on the Space Shuttle, and analyzed in terrestrial laboratories. If ...

Amplification, Next-generation Sequencing, and Genomic DNA Mapping of Retroviral Integration Sites

Retroviruses exhibit signature integration preferences on both the local and global scales. Here, we present a detailed protocol for (1) generation of diverse libraries of retroviral integration sites using ligation-mediated PCR (LM-PCR) amplification and next-generation sequencing (NGS), (2) mapping the genomic location of each virus-host junction using BEDTools, and (3) analyzing the data for statistical relevance. Genomic DNA extracted from infected cells is fragmented by digestion with restriction enzymes or by sonication. After suitable DNA end-repair, double-stranded linkers are ligated onto the DNA ends, and semi-nested PCR is conducted using primers complementary to both the long terminal repeat (LTR) end of the virus and the ligated linker DNA. The PCR primers carry sequences required for DNA clustering during NGS, negating the requirement for separate adapter ligation. Quality control (QC) is conducted to assess DNA fragment size distribution and adapter DNA incorporation prior to NGS. Sequence output files are filtered for LTR-containing reads, and the sequences defining the LTR and the linker are cropped away. Trimmed host cell sequences are mapped to a reference genome using BLAT and are filtered for minimally 97% identity to a unique point in the reference genome. Unique integration sites are scrutinized for adjacent nucleotide (nt) sequence and distribution relative to various genomic features. Using this protocol, integration site libraries of high complexity can be constructed from genomic DNA in three days. The entire protocol that encompasses exogenous viral infection of susceptible tissue culture cells to integration site analysis can therefore be conducted in approximately one to two weeks. Recent applications of this technology pertain to longitudinal analysis of integration sites from HIV-infected patients.

We describe a protocol for amplifying retroviral integration sites from the genomic DNA of infected cells, sequencing the amplified virus-host junctions, and then mapping these sequences to a reference genome. We also describe techniques to quantify the distribution of integration sites relative to various genomic annotations using BEDTools.

레트로 바이러스 통합 사이트의 증폭, 차세대 시퀀싱 및 게놈 DNA 매핑

Retroviruses exhibit signature integration preferences on both the local and global scales. Here, we present a detailed protocol for (1) generation of ...

Visualization of Surface-tethered Large DNA Molecules with a Fluorescent Protein DNA Binding Peptide

Large DNA molecules tethered on the functionalized glass surface have been utilized in polymer physics and biochemistry particularly for investigating interactions between DNA and its binding proteins. Here, we report a method that uses fluorescent microscopy for visualizing large DNA molecules tethered on the surface. First, glass coverslips are biotinylated and passivated by coating with biotinylated polyethylene glycol, which specifically binds biotinylated DNA via avidin protein linkers and significantly reduces undesirable binding from non-specific interactions of proteins or DNA molecules on the surface. Second, the DNA molecules are biotinylated by two different methods depending on their terminals. The blunt ended DNA is tagged with biotinylated dUTP at its 3' hydroxyl terminus, by terminal transferase, while the sticky ended DNA is hybridized with biotinylated complimentary oligonucleotides by DNA ligase. Finally, a microfluidic shear flow makes single DNA molecules stretch to their full contour lengths after being stained with fluorescent protein-DNA binding peptide (FP-DBP).

We present an approach for visualizing fluorescent protein DNA binding peptide (FP-DBP)-stained large DNA molecules tethered on the polyethylene glycol (PEG) and avidin-coated glass surface and stretched with microfluidic shear flows.

펩타이드를 결합 형광 단백질 DNA와 표면 닿는 큰 DNA 분자의 시각화

Large DNA molecules tethered on the functionalized glass surface have been utilized in polymer physics and biochemistry particularly for investigating ...