Name: single liposome measurements for the study of proton-pumping membrane enzymes using electrochemistry and fluorescent microscopy
Uploaded: 2019-02-21T13:00:00
Description: Watch this Scientific Journal Video about Single Liposome Measurements for the Study of Proton-Pumping Membrane Enzymes Using Electrochemistry and Fluorescent Microscopy at JoVE.com

提交人感谢 bbsrc (bbp 00545") 提供的财政支助。nh 由 vilum 基金会青年调查员方案资助。

1. 利皮/uq-10/fdll 混合物的制备
注: 用于脂质体制备的大肠杆菌脂质应在重建。
<ol><li>使用玻璃注射器, 将来自大肠杆菌 (25 mg/ml) 的脂质极性提取物的氯仿库存200μl 转移到玻璃瓶中, 制成5毫克的脂肪。</li>
	<li>在脂类中加入50μml 泛素-10 (uq-10; 氯仿), 使 uq-10 的最终比例为 1:100 (1% ww)。</li>
	<li>在脂肪/uq-10 混合物中加入波长荧光染色脂质 (fdll) 的 20μl (0.4% w w)。...

<ol>
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该方法适用于研究呼吸膜蛋白的质子泵送, 这些蛋白质可以重组为脂质体, 并能与奎宁池交换电子。质子泵送活性可以在单酶水平上监测使用的 ph 敏感 (比例) 染料封装在脂质体腔 (图 1a)。
该方法依赖于泛喹酮 (或其他奎宁) 的能力, 纳入脂质双层, 交换电子与电极修改与 sam18。用 sam 修饰的金电极的性能非常具体。脂质体需要吸附在 sam ?...

有关酶机制和动力学的信息通常是在集合或宏观水平上获得的, 其中酶种群在数千到数百万个分子中, 其中的测量值代表一个统计平均值。然而, 众所周知, 复杂的大分子, 如酶, 可能表现出异质性, 在他们的行为和分子机制观察到的合奏水平不一定是有效的每一个分子。这种在单个分子尺度上的偏差已经通过对单一酶的研究得到了广泛的证实, 在过去 20年中出现了各种方法1。值得注意的是, 荧光检测的单个酶活性已被用来调查酶活性2,3的异质性或发现所谓的记忆效应 (高酶活性的时期, 成功的低时期活动, 反之亦然)4,5。
许多单一的酶研究要求酶固定在表面或空间固定在另一种方式, 以保持足够长的时间在视野中进行连续观测。酶封装到脂质体已被证明能够使酶固定化, 同时防止任何负面影响, 由于表面酶或蛋白质相互作用6,7。此外, 脂质体提供了一个独特的可能性, 研究单膜蛋白在其天然脂质双层环境8,9,10.
一类膜蛋白, 转运体, 在细胞膜上运动物质的定向移位, 这种行为只有在蛋白质重组成脂质双层 (如脂质体)时才能被研究 11, 12,13。例如, 原核和真核电子转运链的几种酶所表现出的质子移位, 通过产生用于 atp 合成的质子动力, 在细胞呼吸中起着重要作用。在这种情况下, 质子泵送活动与电子转移耦合, 尽管这一过程的详细机制往往仍然难以捉摸。
最近, 我们证明了将荧光检测与电化学结合起来研究大肠杆菌末端泛醇氧化酶的质子泵作用的可能性 (细胞色素 b3)重组在脂质体14。这是通过将一种 ph 敏感的膜不透性荧光染料封装到由 e 制备的脂质体腔中来实现的.大肠杆菌极性脂质 (图 1a)。对蛋白质量进行了优化, 使大多数脂质体要么没有或只含有一个重组酶分子 (根据泊松分布)。在脂质体和溶液中的 (环境) 氧中加入泛喹酮, 提供了细胞色素 b3 的两个底物。然后, 脂质体被稀疏地吸附在半透明的超光滑金电极上, 上面覆盖着一个自组装的 6-硫代己醇单层。最后, 电极安装在一个简单的光谱电化学电池的底部 (图 1b)。对奎宁池氧化还原状态的电化学控制允许人们在任何时候灵活触发或停止酶反应, 而 ph 敏感染料则用于监测脂质体腔内的 ph 值变化, 其原因是质子通过酶。利用第二种脂质结合荧光染料的荧光强度, 可以确定单个脂质体的大小和体积, 从而定量酶质子的抽运活性。使用这种技术, 我们发现细胞色素 b3 分子能够 进入自发泄漏状态, 迅速耗散质子的动力。本文的目的是详细介绍单脂质体测量技术。

<table>
	<tbody>
		<tr>
			<td>6-Mercapto-1-hexanol (6MH)</td>
			<td>Sigma</td>
			<td>451088</td>
			<td>97%</td>
		</tr>
		<tr>
			<td>8-hydroxypyrene-1,3,6-trisulphonic acid (HPTS)</td>
			<td>BioChemika</td>
			<td>56360</td>
			<td></td>
		</tr>
		<tr>
			<td>Aluminium holder (Electrochemical cell)</td>
			<td>Custom-made</td>
			<td></td>
			<td>30x30x7 mm; inner diameter: 26 mm; hole diameter: 15 mm</td>
		</tr>
		<tr>
			<td>Auxiliary electrode</td>
			<td></td>
			<td></td>
			<td>platinum wire</td>
		</tr>
		<tr>
			<td>Chloroform</td>
			<td>VWR Chemicals</td>
			<td>83627</td>
			<td></td>
		</tr>
		<tr>
			<td>E.coli polar lipids</td>
			<td>Avanti</td>
			<td>100600C</td>
			<td>25 mg/mL in chloroform</td>
		</tr>
		<tr>
			<td>Epoxy</td>
			<td>EPO-TEK</td>
			<td>301-2FL</td>
			<td>low fluorescence epoxy</td>
		</tr>
		<tr>
			<td>Fiji (ImageJ 1.52d)</td>
			<td></td>
			<td></td>
			<td>Required plugins: StackReg and TurboReg (http://bigwww.epfl.ch/thevenaz/stackreg/)</td>
		</tr>
		<tr>
			<td>Filter cube (&#34;ATTO633&#34;)</td>
			<td>Chroma Technology Corporation</td>
			<td></td>
			<td>Ex: 620/60 nm; DM: 660 nm; Em: 700/75 nm</td>
		</tr>
		<tr>
			<td>Filter cube (&#34;HPTS1&#34;)</td>
			<td>Chroma Technology Corporation</td>
			<td></td>
			<td>Ex: 470/20 nm; DM: 500 nm; Em: 535/48 nm</td>
		</tr>
		<tr>
			<td>Filter cube (&#34;HPTS2&#34;)</td>
			<td>Chroma Technology Corporation</td>
			<td></td>
			<td>Ex: 410/300 nm; DM: 500 nm; Em: 535/48 nm</td>
		</tr>
		<tr>
			<td>Filter cube (&#34;Texas Red&#34;)</td>
			<td>Chroma Technology Corporation</td>
			<td></td>
			<td>Ex: 560/55 nm; DM: 595 nm; Em: 645/75 nm</td>
		</tr>
		<tr>
			<td>Fluorescent dye-labelled lipids (FDLL)</td>
			<td>ThermoFisher Scientific</td>
			<td>T1395MP</td>
			<td>TexasRed-DHPC was used in this work (&#955;exc 595 nm; &#955;em 615 nm)</td>
		</tr>
		<tr>
			<td>Fluorescent dye-labelled lipids (FDLL) (alternative)</td>
			<td>ATTO-TEC</td>
			<td>AD 633-161</td>
			<td>ATTO633-DOPE can be used as alternative (&#955;exc 630 nm; &#955;em 651 nm)</td>
		</tr>
		<tr>
			<td>Gel filtration column</td>
			<td>GE Healthcare</td>
			<td>28-9893-33</td>
			<td>HiLoad 16/600 Superdex 75 pg, for additional protein purification</td>
		</tr>
		<tr>
			<td>Glass coverslips</td>
			<td>VWR International</td>
			<td>631-0172</td>
			<td>No 1.5</td>
		</tr>
		<tr>
			<td>Glass syringe</td>
			<td>Hamilton</td>
			<td>1725 RNR</td>
			<td>250 &#181;L</td>
		</tr>
		<tr>
			<td>Glass vials</td>
			<td>Scientific Glass Laboratories Ltd</td>
			<td>T101/V1</td>
			<td>1.75 mL capacity</td>
		</tr>
		<tr>
			<td>Gold</td>
			<td>GoodFellow</td>
			<td></td>
			<td>99.99%</td>
		</tr>
		<tr>
			<td>Gramacidin</td>
			<td>Sigma</td>
			<td>G5002</td>
			<td></td>
		</tr>
		<tr>
			<td>Mercury sulfate reference electrode</td>
			<td>Radiometer (Hash)</td>
			<td>E21M012</td>
			<td></td>
		</tr>
		<tr>
			<td>Microcentrifuge</td>
			<td>Eppendorf</td>
			<td>Minispin NL040</td>
			<td></td>
		</tr>
		<tr>
			<td>Microscope</td>
			<td>Nikon</td>
			<td>Eclipse Ti</td>
			<td></td>
		</tr>
		<tr>
			<td>Microscope Camera</td>
			<td>Andor</td>
			<td>Zyla 5.5 sCMOS</td>
			<td></td>
		</tr>
		<tr>
			<td>Microscope Lamp</td>
			<td>Nikon</td>
			<td>Intensilight C-HGFI</td>
			<td></td>
		</tr>
		<tr>
			<td>NIS-Elements AR 5.0.2</td>
			<td>Nikon</td>
			<td></td>
			<td>Microscope acquisition software</td>
		</tr>
		<tr>
			<td>n-Octyl &#946;-D-glucopyranoside</td>
			<td>Melford Laboratories</td>
			<td>B2007</td>
			<td></td>
		</tr>
		<tr>
			<td>Nova 1.10</td>
			<td>Metrohm</td>
			<td></td>
			<td>Potentiostat control software</td>
		</tr>
		<tr>
			<td>Objective</td>
			<td>Nikon</td>
			<td>Plan Apo &#955; 60x/1.4 oil</td>
			<td></td>
		</tr>
		<tr>
			<td>OriginPro 2017</td>
			<td>OriginLab</td>
			<td></td>
			<td>Plotting software</td>
		</tr>
		<tr>
			<td>O-ring (Electrochemical cell)</td>
			<td>Orinoko</td>
			<td></td>
			<td>Inner diameter: 16 mm; cross section: 1.5 mm</td>
		</tr>
		<tr>
			<td>Plastic tubes</td>
			<td>Eppendorf</td>
			<td>3810X</td>
			<td>1.5 mL</td>
		</tr>
		<tr>
			<td>Polystyrene microbeads</td>
			<td>Bio-RAD</td>
			<td>152-3920</td>
			<td>Biobeads, 20-50 mesh</td>
		</tr>
		<tr>
			<td>Potentiostat</td>
			<td>Metrohm Autolab</td>
			<td>PGSTAT 128N</td>
			<td></td>
		</tr>
		<tr>
			<td>Potentiostat</td>
			<td>CH Instruments</td>
			<td>CHI604C</td>
			<td></td>
		</tr>
		<tr>
			<td>Scripting software</td>
			<td>Matlab</td>
			<td>R2017a</td>
			<td>Required toolboxes: &#39;Image Processing Toolbox&#39;, &#39;Parallel Computing Toolbox&#39;, &#39;Curve Fitting Toolbox&#39;, &#39;System Identification Toolbox&#39;, &#39;Optimization Toolbox&#39;</td>
		</tr>
		<tr>
			<td>Silicon wafers</td>
			<td>IDB Technologies LTD</td>
			<td>Si-C2 (N&#60;100&#62;P)</td>
			<td>&#216; 25 mm, 525 um thick</td>
		</tr>
		<tr>
			<td>Teflon cell (Electrochemical cell)</td>
			<td>Custom-made</td>
			<td></td>
			<td>Outer diameter: 26 mm; inner diameter: 13.5 mm</td>
		</tr>
		<tr>
			<td>Temple-Stripped Ultra-Flat Gold Surfaces</td>
			<td>Platypus Technologies</td>
			<td>AU.1000.SWTSG</td>
			<td>Alternative ready-to-use ultra-flat gold surfaces (Thickness below 100 nm on demand)</td>
		</tr>
		<tr>
			<td>Thin micropipette tips</td>
			<td>Sarstedt</td>
			<td>70.1190.100</td>
			<td>or similar gelloader tips 200 &#181;L</td>
		</tr>
		<tr>
			<td>Ubiquinone-10</td>
			<td>Sigma</td>
			<td>C-9538</td>
			<td></td>
		</tr>
		<tr>
			<td>Ultracentrifuge</td>
			<td>Beckman-Coulter</td>
			<td>L-80XP</td>
			<td>with Ti 45 rotor</td>
		</tr>
		<tr>
			<td>Ultrasonic bath</td>
			<td>Fisher Scientific</td>
			<td>FB15063</td>
			<td></td>
		</tr>
	</tbody>
</table>

single liposome measurements for the study of proton-pumping membrane enzymes using electrochemistry and fluorescent microscopy

电子转移链的质子泵送酶将氧化还原反应与质子在膜上的移位结合在一起, 形成用于 atp 生产的质子动力。膜蛋白的两亲性需要特别注意它们的处理, 在研究质子转移等膜转运过程时, 重组到天然脂质环境是不可或缺的。在这里, 我们详细介绍了一种方法, 已被用于研究细胞色素博3的膜氧化还原酶的质子泵送机制 , 并以大肠杆菌的细胞色素 b3 为例。电化学和荧光显微镜的结合用于控制奎宁池的氧化还原状态, 并监测腔内的 ph 值变化。由于荧光显微镜的空间分辨率, 可以同时测量数百种脂质体, 而酶含量可以缩小为单个酶或每个脂质体的转运体。相应的单酶分析可以揭示酶功能动力学中的模式, 否则可能会被整个群体的行为所隐藏。我们包括用于自动图像分析的脚本的描述。

在每次电化学阻抗谱实验之前, 对 sam 为6mh 的镀金盖板滑移 (电极) 的质量进行了检验。图 2a显示了在吸附脂质体前后使用电化学阻抗光谱测量的具有代表性的 cole-col 图。如果 sam 的质量是足够的, 阻抗光谱应该证明一个几乎纯粹的电容行为, 导致一个半圆的科尔-科尔图。cole-cole 图形中的半圆直径等于电极表面的双层电容, 该电容应在 2.5-3.0μfcm-2范...

Watch this Scientific Journal Video about Single Liposome Measurements for the Study of Proton-Pumping Membrane Enzymes Using Electrochemistry and Fluorescent Microscopy at JoVE.com

Single Liposome Measurements for the Study of Proton-Pumping Membrane Enzymes Using Electrochemistry and Fluorescent Microscopy

电化学和荧光显微镜在质子泵膜酶研究中的单脂质体测定

在这里, 我们提出了一个方案, 研究质子在单个脂质体脂质膜上的分子转移机制, 以细胞色素b3 为例。结合电化学和荧光显微镜, 可以单独检测和分析含有单一或多种酶的单囊腔内的 ph 值变化。

Proton-pumping enzymes of electron transfer chains couple redox reactions to proton translocation across the membrane, creating a proton-motive force used ...

该方法允许在天然脂质双层环境中研究呼吸膜酶（如细胞色素BO3）的质子传输活性。这种单一酶技术的主要优点是有可能开始和停止酶反应在任何时刻使用电化学。使用玻璃注射器将200微升氯仿从大肠杆菌中提取的脂质极性提取物转移到玻璃瓶中，制成5毫克等同。将50微升，每毫升一毫克，在脂质中加入10微升，使1至100比10的泛素10与脂质的最终比例。在混合物中加入20微升，每毫升长波长度1毫克的荧光染料，标有脂质缩写FDLL。通过短涡使氯仿溶液均质，并在温和的氮气或砷流下蒸发大部分氯仿。完全去除氯仿痕迹，在真空下进一步蒸发至少一小时。加入 312.5 微升 40 毫摩尔 MOPS pH 7.4 缓冲液到一个脂质泛素 10 FDLL 干混合。混合涡流，直到脂质膜完全重新悬浮，然后两分钟在超声波浴中治疗。接下来加入125微升25毫摩尔HPTS，一种pH敏感荧光染料，将封装在脂质体内。现在添加 137.5 微升 250 毫摩尔 OGP 表面活性剂。使用涡流混合后，在超声波水浴中对混合物进行声波处理10分钟，以确保所有脂质都溶解成表面活性色球。然后将分散体转移到1.5毫升塑料管中。加入所需的细胞色素 BO3 量，并加入超纯水，使总体积达到 50 微升。在4摄氏度下在滚筒搅拌机上孵育重组混合物10分钟。接下来，在两个1.5毫升管盖中，每个都重50毫克聚苯乙烯微珠。然后将 100 毫克聚苯乙烯微珠重到另外两个 1.5 毫升管盖中。用石蜡膜合上瓶盖，防止干燥。将前 50 毫克聚苯乙烯微珠加入重组混合物中，将带聚苯乙烯微珠的盖子放在 1.5 毫升塑料管上，并准备好的分散剂。然后执行短旋转几秒钟，将微珠带到管的底部。在滚筒搅拌机上孵育4摄氏度的悬浮液，使聚苯乙烯微珠吸收表面活性剂30分钟。重复添加聚苯乙烯微珠和孵育，如下所示。加入50毫克微珠，进行60分钟的孵育。然后加入100毫克微珠，进行60分钟的孵育。最后，加入100毫克微珠进行120分钟的孵育。使用带薄尖端的微管将蛋白糖体溶液与聚苯乙烯微珠分离。稀释 TI 45 超离心管中 90 毫升 MOPS 缓冲液中的分散。使用 45 TI 转子在 125，000 次 G 下进行超离射一小时，以对蛋白体进行颗粒化。超离心后，丢弃上清液，用 MOPS 缓冲液冲洗颗粒，无需重新暂停颗粒。丢弃冲洗缓冲液后，在将悬浮液转移到 1.5 毫升塑料管之前，将悬浮在 500 微升 MOPS 缓冲液中，用薄尖微管来回移液。在12，000次G下离心5分钟后，将上经液（即重组的蛋白酶体）转移到一个新的小瓶中。使用双组分低荧光环氧树脂将多达九个玻璃盖粘在蒸发的黄金表面。在80摄氏度下固化胶水4小时。在使用自组装的单层进行修改之前，用刀片将玻璃盖滑从硅胶晶圆上分离。由于盖滑件很薄，拆卸盖滑时应小心，不要破裂或打破玻璃滑梯。将刚分离的镀金涂层滑入 6 马卡普托赫萨醇溶液中，在 20 至 25 摄氏度下过夜，形成自组装的单层。第二天，从溶液中去除镀金盖滑，用水或甲醇短暂清洗，然后用异丙醇清洗。在温和的气流下干燥镀金盖滑。如文本协议所示，将镀金盖滑在光谱电化学电池中组装。在橡胶 O 环定义的区域外用扁平导线与黄金接触，并拧紧其顶部的电化学电池。加入两毫升电解质缓冲液，并将参考电极和辅助电极放在电池中。继续检查自组装单层的质量，并运行文本协议中描述的空白。以每毫升0.5毫克最终脂质浓度向电化学细胞中加入蛋白糖体，并稍微与移液器混合。在室温下等待 30 到 60 分钟，直到电极表面的蛋白体体吸收完成。通过更换缓冲液至少 10 次来清洗电池，但避免使电极表面完全干燥。现在，在开放细胞电位下运行电化学阻抗光谱，以确认金电极上自组装的单层保持不变。运行循环伏特图，扫描速率为10和100毫伏/秒，以观察细胞色素BO3在电化学奎诺还原的启动潜力下进行泛醇氧化和氧减少。修改金电极一样，但使用五微克每毫升蛋白糖体。对于单酶研究，将细胞色素BO3与脂质比降至0.1至0.2%之间，将浸入油滴，然后在倒置荧光显微镜的60倍油量目标上放置电化学细胞。使用适当的FDLL荧光滤波器，聚焦电极表面。单脂体应作为显微镜目标衍射极限的亮点出现。以 FDLL 花光的图像。切换到显微镜上的 HPTS 荧光滤光片集，以验证 HTPS 荧光是否清晰可见，并且与背景有区别。如果不是这样，增加光强。通过交替两个HTPS滤波器集对显微镜软件进行编程，以执行定时图像采集。为此，请设置一秒曝光，然后导航到菜单应用程序。然后定义/运行 ND 采集并选择两个 HTPS 通道。将图像采集之间的延迟设置为最小。在此实验中，使用 0.3 秒延迟和 5 分钟的总持续时间。调整电位设置以更改图像采集过程中的潜力，如文本协议中所示。现在，通过同时手动启动两个测量，在显微镜上同时运行时间图像采集和电位统计中的潜在序列。此处显示的荧光图像是三个不同覆盖范围在电极上吸收的脂质体。含有脂质体的染料在图像上可见为亮点。图像的中心部分被照片漂白，以揭示背景荧光水平。两个 HTPS 通道上的图像是超级不可假定的，其中两个通道之间的比率对应于本实验中使用的 pH 值 7.4。FDLL 通道可以看到更多的脂质体，表示存在没有 HPTS 封装的脂质体。HPTS 和 FDLL 通道之间的差异在高覆盖范围下更为明显。可能是因为在高脂质体覆盖时，脂质体更容易在表面破裂或熔断。在这里，在实验的300秒内，两个HTPS通道上的脂体花数的变化显示为相应区域的3D曲面图。还原电位在 60 秒到 180 秒之间应用。显示了两个 HPTS 通道与时间之间的体积公制强度比的相应图。此处显示的是当细胞色素 BO3 含量为 1.3% 时，单个图像中所有囊泡 pH 值变化的中位数，当应用 0.1 和 0.3 伏特之间的电位时，pH 值的增加清晰可见。当细胞色素 BO3 含量低得多 0.1% 时，中位曲线与空脂质体曲线几乎无法区分。确保从脂质体分布中完全去除表面活性剂非常重要，因为残余体可能会增加脂质体对质子的渗透性。这些方法使我们能够对天然嗜脂奎诺基质提出具体问题，与经常使用的水溶性奎诺类比相反。此外，单一酶实验确定了以前未知的泄漏状态，其中蛋白质充当质子通道，质子可以自由向后流动。

Research

JoVE Journal

Biochemistry

High-throughput Screening of Carbohydrate-degrading Enzymes Using Novel Insoluble Chromogenic Substrate Assay Kits

使用新型不溶性生色底物检测试剂盒碳水化合物降解酶的高通量筛选

Carbohydrates active enzymes (CAZymes) have multiple roles in vivo and are widely used for industrial processing in the biofuel, textile, detergent, paper ...

科研

生物化学

Single-molecule Super-resolution Imaging of Phosphatidylinositol 4,5-bisphosphate in the Plasma Membrane with Novel Fluorescent Probes

在质膜用新型荧光探针磷脂酰-4,5-二磷酸的单分子超分辨率成像

Phosphoinositides in the cell membrane are signaling lipids with multiple cellular functions. Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) is a ...

Using Scaffold Liposomes to Reconstitute Lipid-proximal Protein-protein Interactions In Vitro

Using Scaffold Liposomes to Reconstitute Lipid-proximal Protein-protein Interactions In Vitro

使用脚手架脂质体重构脂质近端蛋白质 - 蛋白质相互作用<em&gt;体外</em

Studies of integral membrane proteins in vitro are frequently complicated by the presence of a hydrophobic transmembrane domain. Further complicating ...

High-resolution Single Particle Analysis from Electron Cryo-microscopy Images Using SPHIRE

使用SPHIRE的电子冷冻显微镜图像的高分辨率单粒子分析

SPHIRE (SPARX for High-Resolution Electron Microscopy) is a novel open-source, user-friendly software suite for the semi-automated processing of single ...

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 ...

Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase

Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase

用 [NiFe] 氢对 H2氧化的研究表明, 蛋白质膜红外电化学

Understanding the chemistry of redox proteins demands methods that provide precise control over redox centers within the protein. The technique of protein ...

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 ...

A Fluorescence Fluctuation Spectroscopy Assay of Protein-Protein Interactions at Cell-Cell Contacts

细胞细胞接触物蛋白质-蛋白质相互作用的荧光波动光谱测定

A variety of biological processes involves cell-cell interactions, typically mediated by proteins that interact at the interface between neighboring ...

Production of Dynein and Kinesin Motor Ensembles on DNA Origami Nanostructures for Single Molecule Observation

生产用于单分子观察的DNA折纸纳米结构的Dynein和Kinesin电机组合

Cytoskeletal motors are responsible for a wide variety of functions in eukaryotic cells, including mitosis, cargo transport, cellular motility, and ...

Visualizing Diffusional Dynamics of Gold Nanorods on Cell Membrane using Single Nanoparticle Darkfield Microscopy

使用单纳米粒子暗场显微镜可视化细胞膜上金纳米棒的扩散动力学

Analyzing the diffusional dynamics of nanoparticles on cell membrane plays a significant role in better understanding the cellular uptake process and ...