Name: single-molecule manipulation of g-quadruplexes by magnetic tweezers
Uploaded: 2017-09-19T14:00:00
Description: Watch this Scientific Journal Video about Single-molecule Manipulation of G-quadruplexes by Magnetic Tweezers at JoVE.com

作者感谢孟潘校对手稿。这项工作得到新加坡教育部学术研究基金3层 (MOE2012-T3-1-001) 对彼莱的支持;国家研究基金会通过 Mechanobiology 研究所新加坡彼莱;国家研究基金会, 新加坡总理办公室, 根据其 NRF Investigatorship 方案 (NRF Investigatorship 奖 No。NRF-NRFI2016-03 到彼莱;中央大学基础研究基金 (2017KFYXJJ153) h.y。

1. 单分子拉伸的 G4 DNA 的制备 <ol> <li> 准备5和 #39;-巯基标记和5和 #39;-生物素标记 dsDNA 处理, 使用 DDNA 聚合酶在 lambda 噬菌体 DNA 模板上使用5和 #39;-巯基和5和 #39;-生物素引物 14 ( 图 1 )。两个 dsDNA 处理都具有高 GC 含量 (和 #62; 60%), 以防止 dna 在高力量或 dna 过度过渡过程中的 dna 熔化 15 . </li>
	<li> 根据制造商和 #39 的协议, 使用商业纯化试...

<ol>
	<li>Rhodes, D., Lipps, H. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=G-quadruplexes+and+their+regulatory+roles+in+biology.">G-quadruplexes and their regulatory roles in biology.</a> Nucleic Acids Res. 43 (18), 8627-8637 (2015).</li><li>Brazda, V., Haronikova, L., Liao, J. C., Fojta, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=DNA+and+RNA+quadruplex-binding+proteins.">DNA and RNA quadruplex-binding proteins.</a> Int J Mol Sci. 15 (10), 17493-17517 (2014).</li><li>Gonzalez, V., Hurley, L. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+C-terminus+of+nucleolin+promotes+the+formation+of+the+c-MYC+G-quadruplex+and+inhibits+c-MYC+promoter+activity.">The C-terminus of nucleolin promotes the formation of the c-MYC G-quadruplex and inhibits c-MYC promoter activity.</a> Biochemistry. 49 (45), 9706-9714 (2010).</li><li>Wang, F., 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=telomerase-interacting+protein+that+unfolds+telomere+G-quadruplex+and+promotes+telomere+extension+in+mammalian+cells.">telomerase-interacting protein that unfolds telomere G-quadruplex and promotes telomere extension in mammalian cells.</a> Proc Natl Acad Sci U S A. 109 (50), 20413-20418 (2012).</li><li>Mendoza, O., Bourdoncle, A., Boule, J. B., Brosh, R. M., Mergny, J. 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C., Nagy, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Single-molecule+force+spectroscopy:+optical+tweezers,+magnetic+tweezers+and+atomic+force+microscopy.">Single-molecule force spectroscopy: optical tweezers, magnetic tweezers and atomic force microscopy.</a> Nat Methods. 5 (6), 491-505 (2008).</li><li>Chen, H., 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=Improved+high-force+magnetic+tweezers+for+stretching+and+refolding+of+proteins+and+short+DNA.">Improved high-force magnetic tweezers for stretching and refolding of proteins and short DNA.</a> Biophys J. 100 (2), 517-523 (2011).</li><li>Chen, H., 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=Dynamics+of+equilibrium+folding+and+unfolding+transitions+of+titin+immunoglobulin+domain+under+constant+forces.">Dynamics of equilibrium folding and unfolding transitions of titin immunoglobulin domain under constant forces.</a> J Am Chem Soc. 137 (10), 3540-3546 (2015).</li><li>You, H., Wu, J., Shao, F., Yan, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stability+and+kinetics+of+c-MYC+promoter+G-quadruplexes+studied+by+single-molecule+manipulation.">Stability and kinetics of c-MYC promoter G-quadruplexes studied by single-molecule manipulation.</a> J Am Chem Soc. 137 (7), 2424-2427 (2015).</li><li>You, H., Lattmann, S., Rhodes, D., Yan, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=RHAU+helicase+stabilizes+G4+in+its+nucleotide-free+state+and+destabilizes+G4+upon+ATP+hydrolysis.">RHAU helicase stabilizes G4 in its nucleotide-free state and destabilizes G4 upon ATP hydrolysis.</a> Nucleic Acids Res. 45 (1), 206-214 (2017).</li><li>You, H., 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=Dynamics+and+stability+of+polymorphic+human+telomeric+G-quadruplex+under+tension.">Dynamics and stability of polymorphic human telomeric G-quadruplex under tension.</a> Nucleic Acids Res. 42 (13), 8789-8795 (2014).</li><li>Fu, H., Chen, H., Marko, J. F., Yan, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two+distinct+overstretched+DNA+states.">Two distinct overstretched DNA states.</a> Nucleic Acids Res. 38 (16), 5594-5600 (2010).</li><li>Gosse, C., Croquette, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+tweezers:+micromanipulation+and+force+measurement+at+the+molecular+level.">Magnetic tweezers: micromanipulation and force measurement at the molecular level.</a> Biophys. J. 82 (6), 3314-3329 (2002).</li><li>Fu, H., 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=Transition+dynamics+and+selection+of+the+distinct+S-DNA+and+strand+unpeeling+modes+of+double+helix+overstretching.">Transition dynamics and selection of the distinct S-DNA and strand unpeeling modes of double helix overstretching.</a> Nucleic Acids Res. 39 (8), 3473-3481 (2011).</li><li>Zhang, X., Chen, H., Fu, H., Doyle, P. S., Yan, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two+distinct+overstretched+DNA+structures+revealed+by+single-molecule+thermodynamics+measurements.">Two distinct overstretched DNA structures revealed by single-molecule thermodynamics measurements.</a> Proc Natl Acad Sci U S A. 109 (21), 8103-8108 (2012).</li><li>Zhang, 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=Revealing+the+competition+between+peeled+ssDNA,+melting+bubbles,+and+S-DNA+during+DNA+overstretching+by+single-molecule+calorimetry.">Revealing the competition between peeled ssDNA, melting bubbles, and S-DNA during DNA overstretching by single-molecule calorimetry.</a> Proc Natl Acad Sci U S A. 110 (10), 3865-3870 (2013).</li><li>Chen, H., 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=Improved+High-Force+Magnetic+Tweezers+for+Stretching+and+Refolding+of+Proteins+and+Short+DNA.">Improved High-Force Magnetic Tweezers for Stretching and Refolding of Proteins and Short DNA.</a> Biophys. J. 100 (2), 517-523 (2011).</li><li>Fu, H. 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=Transition+dynamics+and+selection+of+the+distinct+S-DNA+and+strand+unpeeling+modes+of+double+helix+overstretching.">Transition dynamics and selection of the distinct S-DNA and strand unpeeling modes of double helix overstretching.</a> Nucleic Acids Res. 39 (8), 3473-3481 (2011).</li><li>Zhang, X., Chen, H., Fu, H., Doyle, P. S., Yan, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two+distinct+overstretched+DNA+structures+revealed+by+single-molecule+thermodynamics+measurements.">Two distinct overstretched DNA structures revealed by single-molecule thermodynamics measurements.</a> Proc. Natl. Acad. Sci. U.S.A. 109 (21), 8103-8108 (2012).</li><li>Zhang, 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=Revealing+the+competition+between+peeled+ssDNA,+melting+bubbles,+and+S-DNA+during+DNA+overstretching+by+single-molecule+calorimetry.">Revealing the competition between peeled ssDNA, melting bubbles, and S-DNA during DNA overstretching by single-molecule calorimetry.</a> Proc. Natl. Acad. Sci. U.S.A. 110 (10), 3865-3870 (2013).</li><li>Vaughn, J. P., 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+DEXH+protein+product+of+the+DHX36+gene+is+the+major+source+of+tetramolecular+quadruplex+G4-DNA+resolving+activity+in+HeLa+cell+lysates.">The DEXH protein product of the DHX36 gene is the major source of tetramolecular quadruplex G4-DNA resolving activity in HeLa cell lysates.</a> J Biol Chem. 280 (46), 38117-38120 (2005).</li><li>Giri, B., 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=G4+resolvase+1+tightly+binds+and+unwinds+unimolecular+G4-DNA.">G4 resolvase 1 tightly binds and unwinds unimolecular G4-DNA.</a> Nucleic Acids Res. 39 (16), 7161-7178 (2011).</li><li>De Vlaminck, I., Dekker, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+advances+in+magnetic+tweezers.">Recent advances in magnetic tweezers.</a> Annu Rev Biophys. 41, 453-472 (2012).</li><li>Yan, J., Skoko, D., Marko, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Near-field-magnetic-tweezer+manipulation+of+single+DNA+molecules.">Near-field-magnetic-tweezer manipulation of single DNA molecules.</a> Phys Rev E Stat Nonlin Soft Matter Phys. 70 (1 Pt 1), 011905 (2004).</li><li>Le, 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=Disturbance-free+rapid+solution+exchange+for+magnetic+tweezers+single-molecule+studies.">Disturbance-free rapid solution exchange for magnetic tweezers single-molecule studies.</a> Nucleic Acids Res. 43 (17), e113 (2015).</li><li>Neidle, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quadruplex+Nucleic+Acids+as+Novel+Therapeutic+Targets.">Quadruplex Nucleic Acids as Novel Therapeutic Targets.</a> J Med Chem. 59 (13), 5987-6011 (2016).</li><li>Simone, R., Fratta, P., Neidle, S., Parkinson, G. N., Isaacs, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=G-quadruplexes:+Emerging+roles+in+neurodegenerative+diseases+and+the+non-coding+transcriptome.">G-quadruplexes: Emerging roles in neurodegenerative diseases and the non-coding transcriptome.</a> FEBS Lett. 589 (14), 1653-1668 (2015).</li><li>Balasubramanian, S., Hurley, L. H., Neidle, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeting+G-quadruplexes+in+gene+promoters:+a+novel+anticancer+strategy?.">Targeting G-quadruplexes in gene promoters: a novel anticancer strategy?.</a> Nat Rev Drug Discov. 10 (4), 261-275 (2011).</li><li>Amato, 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=Toward+the+Development+of+Specific+G-Quadruplex+Binders:+Synthesis,+Biophysical,+and+Biological+Studies+of+New+Hydrazone+Derivatives.">Toward the Development of Specific G-Quadruplex Binders: Synthesis, Biophysical, and Biological Studies of New Hydrazone Derivatives.</a> J Med Chem. 59 (12), 5706-5720 (2016).</li><li>Wells, R. 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如上所述, 一个研究 G4 DNA 的机械稳定性的平台和 G4 使用分子磁性镊子的蛋白质相互作用的报告。在该平台的基础上, 开发了高效的 G4 DNA 链, 并对 G4 结构的折叠展开动力学和稳定性进行了测量。焦平面锁定使高度稳定的抗控制, 这是重要的检测小结构转变, 如 G4 (步长〜 7 nm) 和与蛋白质的相互作用在缓冲交换实验。该平台最近被用于研究端 G414和 c-myc 启动子 G412?...

四-搁浅的 DNA 或 RNA G4 结构在许多重要的生物过程中扮演重要角色1。许多蛋白质涉及 G4 结合和调节, 包括端粒结合蛋白 (端粒酶, POT1, RPA, TEBPs, TRF2)1,2, 转录因子 (核仁, PARP1)3, RNA 处理蛋白 (hnRNP A1,hnRNP A2)4, 旋 (土地管理局, FANCJ, RHAU, 警告, Dna2, Pif1)5, 和 DNA 复制相关的蛋白质 (Rif1, REV1, PrimPolymerase)6。蛋白质结合能稳定或破坏 G4 结构;从而调节后续的生物功能。采用紫外 (UV) 或循环二 (CD) 方法测定了 G4 的稳定性.7。然而, 这些条件是不生理相关的, 很难适用于研究结合蛋白的影响7。
在分子操作技术的快速发展, 使研究的折叠和展开的生物, 如 DNA 或蛋白质, 在分子水平与纳米分辨率实时8。原子力显微镜 (AFM)、光镊和磁性镊子是最常用的分子操作方法。与 AFM 和光学镊子9相比, 磁性镊子可以使用抗技术10、11, 在几天内稳定地测量单个分子的折叠展开动力学。
在这里, 一个分子操作平台使用磁性镊子研究 G4 稳定性的调节结合蛋白报告12,13。这项工作概述了基本的方法, 包括样品和流动通道的准备, 磁性镊子的设置, 和力量校准。3步所述的力控制和抗协议允许在各种力控制下进行长时间测量, 如恒定力 (力钳) 和恒定加载速率 (力-斜坡) 和力跃测量。4步中描述的力校准协议使 #60 的力标定; 1 µm 短系超过 100 pN, 相对误差在10% 以内。在解析 rna G4R1 中扮演重要角色的 rna 旋与富金元素 (RHAU) 旋 (别名 DHX36, G4) 的稳定性的调节示例用于演示此平台13的应用程序。

<table>
	<tbody>
		<tr>
			<td>DNA PCR primers</td>
			<td>IDT</td>
			<td></td>
			<td>DNA preparations</td>
		</tr>
		<tr>
			<td>DNA PCR chemicals</td>
			<td>NEB</td>
			<td></td>
			<td>DNA preparations</td>
		</tr>
		<tr>
			<td>restriction enzyme BstXI</td>
			<td>NEB</td>
			<td>R0113S</td>
			<td>DNA preparations</td>
		</tr>
		<tr>
			<td>coverslips (#1.5, 22*32 mm, and 20*20 mm)</td>
			<td>BMH.BIOMEDIA</td>
			<td>72204</td>
			<td>flow channel preparation</td>
		</tr>
		<tr>
			<td>Decon90</td>
			<td>Decon Laboratories Limited</td>
			<td></td>
			<td>flow channel preparation</td>
		</tr>
		<tr>
			<td>APTES</td>
			<td>Sigma</td>
			<td>440140-500ML</td>
			<td>flow channel preparation</td>
		</tr>
		<tr>
			<td>Sulfo-SMCC</td>
			<td>ThermoFisher Scientific</td>
			<td>22322</td>
			<td>flow channel preparation</td>
		</tr>
		<tr>
			<td>M-280, paramganetic beads,streptavidin</td>
			<td>ThermoFisher Scientific</td>
			<td>11205D</td>
			<td>flow channel preparation</td>
		</tr>
		<tr>
			<td>Polybead Amino Microspheres 3.00 &#956;m</td>
			<td>Polysciences, Inc</td>
			<td>17145-5</td>
			<td>flow channel preparation</td>
		</tr>
		<tr>
			<td>2-Mercaptoethanol</td>
			<td>Sigma</td>
			<td>M6250-250ML</td>
			<td>flow channel preparation</td>
		</tr>
		<tr>
			<td>Olympus Microscopes IX71</td>
			<td>Olympus</td>
			<td>IX71</td>
			<td>Magnetic tweezers setup</td>
		</tr>
		<tr>
			<td>Piezo-Z Stages P-721</td>
			<td>Physik Instrumente</td>
			<td>P-721</td>
			<td>Magnetic tweezers setup</td>
		</tr>
		<tr>
			<td>Olympus Objective lense MPLAPON-Oil 100X</td>
			<td>Olympus</td>
			<td>MPLAPON-Oil 100X</td>
			<td>Magnetic tweezers setup</td>
		</tr>
		<tr>
			<td>CCD/CMOS camera</td>
			<td>AVT</td>
			<td>Pike F-032B</td>
			<td>Magnetic tweezers setup</td>
		</tr>
		<tr>
			<td>Translation linear stage</td>
			<td>Physik Instrumente</td>
			<td>MoCo DC</td>
			<td>Magnetic tweezers setup</td>
		</tr>
		<tr>
			<td>LED</td>
			<td>Thorlabs</td>
			<td>MCWHL</td>
			<td>Magnetic tweezers setup</td>
		</tr>
		<tr>
			<td>Cubic Magnets</td>
			<td>Supermagnete</td>
			<td></td>
			<td>Magnetic tweezers setup</td>
		</tr>
		<tr>
			<td>Labview</td>
			<td>National Instruments</td>
			<td></td>
			<td>Magnetic tweezers setup</td>
		</tr>
		<tr>
			<td>OriginPro/Matlab</td>
			<td>OriginLab/MathWorks</td>
			<td></td>
			<td>Data analysis</td>
		</tr>
	</tbody>
</table>

single-molecule manipulation of g-quadruplexes by magnetic tweezers

非标准核酸二级结构 G quadruplexes (G4) 涉及不同的细胞过程, 如 DNA 复制, 转录, RNA 处理, 和端粒伸长。在这些过程中, 各种蛋白质结合, 并解决 G4 结构, 以履行其功能。由于 G4 的功能往往取决于其折叠结构的稳定性, 所以研究 G4 结合蛋白如何调节 G4 的稳定性是很重要的。这项工作提出了一种使用磁性镊子操作单 G4 分子的方法, 它能够研究 G4 结合蛋白在单个 G4 分子上的实时调节。一般而言, 这种方法适用于研究蛋白质/配体相互作用和各种 DNA 或 RNA 二级结构的规则的广泛应用。

在图 4中显示了拉伸单个 G4 分子的实验装置。在两个 dsDNA 手柄之间的单 G4 形成序列被拴在片和顺磁珠之间。为了找到一个单一的 dsDNA 栓珠, 通过在恒定加载速率下增加力来进行过度试验。三种测量方法通常用于研究生物分子的折叠和展开: (i) 恒定力测量, (ii) 力-斜坡测量, 和 (iii) 力跳跃测量。由于这个 G4 结构的非常缓慢的展开速率, 平衡折叠展开的...

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Single-molecule Manipulation of G-quadruplexes by Magnetic Tweezers

磁性镊子 quadruplexes 单分子操作

报道了一种分子磁镊 quadruplexes 的操作平台, 可以对各种蛋白质的 G4 稳定性和调节进行研究。

Non-canonical nucleic acid secondary structure G-quadruplexes (G4) are involved in diverse cellular processes, such as DNA replication, transcription, RNA ...

Research

JoVE Journal

Biochemistry

High Precision FRET at Single-molecule Level for Biomolecule Structure Determination

单分子水平的高精度FRET用于生物分子结构测定

A protocol on how to perform high-precision interdye distance measurements using F&#246;rster resonance energy transfer (FRET) at the single-molecule ...

科研

生物化学

Using Three-color Single-molecule FRET to Study the Correlation of Protein Interactions

应用三色单分子焦虑研究蛋白质相互作用的相关性

Single-molecule F&#246;rster resonance energy transfer (smFRET) has become a widely used biophysical technique to study the dynamics of biomolecules. For ...

Covalent Immobilization of Proteins for the Single Molecule Force Spectroscopy

单分子力谱中蛋白质共价固定化的研究

In recent years, atomic force microscopy (AFM) based single molecule force spectroscopy (SMFS) extended our understanding of molecular properties and ...

Proteome-wide Quantification of Labeling Homogeneity at the Single Molecule Level

单分子水平标记均匀性的全蛋白质定量

Cell proteomes are often characterized using electrophoresis assays, where all species of proteins in the cells are non-specifically labeled with a ...

Single-Molecule Tracking Microscopy - A Tool for Determining the Diffusive States of Cytosolic Molecules

单分子跟踪显微镜 - 确定细胞分子扩散状态的工具

Single-molecule localization microscopy probes the position and motions of individual molecules in living cells with tens of nanometer spatial and ...

Conventional BODIPY Conjugates for Live-Cell Super-Resolution Microscopy and Single-Molecule Tracking

用于活细胞超分辨率显微镜和单分子跟踪的传统 BODIPY 结合物

Single molecule localization microscopy (SMLM) techniques overcome the optical diffraction limit of conventional fluorescence microscopy and can resolve ...

Single Cell Analysis Of Transcriptionally Active Alleles By Single Molecule FISH

单分子鱼的转录活性等位基因单细胞分析

Gene transcription is an essential process in cell biology, and allows cells to interpret and respond to internal and external cues. Traditional bulk ...

Single Molecule Fluorescence Energy Transfer Study of Ribosome Protein Synthesis

单分子荧光能量转移研究核糖体蛋白质合成

The ribosome is a large ribonucleoprotein complex that assembles proteins processively along mRNA templates. The diameter of the ribosome is approximately ...

Single-Molecule Imaging of EWS-FLI1 Condensates Assembling on DNA

The fusion genes resulting from chromosomal translocation have been found in many solid tumors or leukemia. EWS-FLI1, which belongs to the FUS/EWS/TAF15 ...

An Optimized Single-Molecule Pull-Down Assay for Quantification of Protein Phosphorylation

用于蛋白质磷酸化定量的优化单分子下拉测定

Phosphorylation is a necessary posttranslational modification that regulates protein function and directs cell signaling outcomes. Current methods to ...