Name: visualization of dna repair proteins interaction by immunofluorescence
Uploaded: 2020-06-26T14:45:00
Description: Watch this Scientific Journal Video about Visualization of DNA Repair Proteins Interaction by Immunofluorescence at JoVE.com

这项工作得到了圣安东尼奥地区基金会的赠款的支持。Mays 癌症中心由 NCI 癌症中心支持核心赠款 P30 CA054174 提供支持。我们要感谢斯蒂芬·霍洛韦帮助采购试剂，感谢宋实验室提供空间和显微镜容量。

1. 希拉细胞培养
<ol><li>在 50°C 下预处理带 1 M HCl 的圆形玻璃盖玻片，使用 16-18 小时。用 ddH2O 冲洗，并储存在 100% Etoh 中。</li>
	<li>准备细胞培养基：向DMEM培养基添加10%（v/v）FBS。</li>
	<li>在无菌 12 井板中生长 4.0 x10 4 细胞/井，在加湿培养箱中用 18 mm 圆形玻璃盖玻片和 5%CO2。 将细胞生长到80%的汇合（约24小时）。</li>
</ol>2. 放射治疗的细胞治疗
<ol><li>?...

<ol>
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通过显微镜分析DNA损伤修复的时机和效率，已证明对了解DNA修复机械在正常细胞和人类疾病（如癌症）中如何工作至关重要。
特异性抗体的培养，允许检测活性蛋白在其磷酸化版本（如+H2AX，pRPA，pRAD50和其他10，23，39，43）,39,43在更好地了解DNA修复时间的事件及其与细胞周期的同步。10<su...

人类细胞不断暴露在各种来源的DNA破坏剂中。外源主要包括接触辐射、化学品（包括化疗剂和某些抗生素）和病毒，而主要的内源包括DNA复制和氧化应激方面的错误。基因毒性暴露的直接影响范围从改良的碱基到潜在的致命DNA双链断裂（DSB），这取决于压力和暴露剂量。最终，未修复或修复不当的DNA损伤可导致突变的积累、基因组重组、基因组不稳定，并最终导致致癌1。哺乳动物细胞已经进化出复杂的途径来识别特定类型的DNA损伤2,2，3，并及时修复它们，与细胞周期进展同步。
电离辐射（IR）损害DNA双螺旋，并造成双链断裂（DSB），这是最有害的DNA损伤形式之一。MRN （MRE11， RAD50， NBS1） 复合功能作为 DNA 末端的传感器，并激活蛋白激酶 ataxia telangiectasia 突变 （ATM）4，5。在DNA端对ATM的初始激活后，ATM在断点触发一系列DDR事件，启动一个关键事件，即组蛋白变种H2AX6的磷酸化。在残留物S139上的H2AX磷酸化激活它到+H2AX，跨越区域，高达围绕DNA病变6，7，8，97,8的巨型碱。6这一事件增加了DNA的可访问性，导致其他DNA修复蛋白的招募和积累7。由于 +H2AX 是丰富和具体诱导周围的 DSB，它可以很容易地可视化使用特定的抗体，并通常用作 DSB 在 DNA 修复领域的代理标记。一旦中断被发出信号，细胞激活其DNA修复途径并处理DNA损伤。蛋白质MDC1（DNA损伤检查点蛋白1的中介）直接结合+H2AX10，与ATM11和NBS1 12，13,相互作用。它有助于提高 MRN 复合物在 DSB 的浓度，并启动正 ATM 反馈回路。•一旦修复断裂，快速清除H2AX，从而允许监控DSB间隙。其次是显微镜，随着时间的推移，μH2AX 的减少提供了残余断裂和 DNA 修复效率的间接测量。
真核细胞可以通过多种途径修复DSB，两个主要途径是非同源端连接（NHEJ）和同源重组（HR）（图1）。NHEJ基本上连接DNA双链结束不使用扩展同源和在整个细胞周期14，15运行。14,HR在S和G2阶段成为占主导地位，否则被压抑，因为它需要一个姐妹色度作为一个同源模板修复14，16。14,NHEJ和HR之间的路径选择不仅取决于姐妹色度的物理接近性，还取决于DNA端切除17的延伸，它抑制了NHEJ。
同源性依赖的DSB修复启动核解降解的5'链从断裂端产生3'单链DNA（ssDNA）尾部，这个过程被称为5'-3'切除。MRN复合物启动DNA端切除术，并结合BLM/EXO1（布洛姆综合征蛋白/外核酶1）或BLM/DNA2（DNA复制ATP依赖性直升机酸酶,/核酸酶）18、19、20、21、22,19,20进行进一,步切除。21CtIP（CtBP相互作用蛋白）通过与 MRN 复合物23的直接相互作用和 BRCA1（乳腺癌 1 型易感性蛋白）24，25的招募来增强 DNA 末切。复制蛋白A（RPA）迅速结合到暴露的ssDNA，然后被重组酶蛋白RAD51取代，形成核蛋白丝，催化同源搜索和链入侵26，27，28。26,27,28
切除的启动是修复路径选择的关键步骤。一旦切除开始，DNA末端成为由Ku70/Ku80异质剂（NHEJ通路的组成部分）结合的不良基质，细胞被承诺到HR 17，29，30。17,29,30Ku70/Ku80异质剂结合到DSB末端，招募DNA-PKcs和p53结合蛋白,1（53BP1）29，2930。53BP1在G1中起到切除屏障的作用，从而在推广NHEJ31、32,32的同时阻断HR，但在S相中以BRCA1依赖的方式去除，从而允许切除发生33，34,34。因此，53BP1 和 BRCA1 在 DSB 维修中扮演相反的角色，53BP1 是 NHEJ 促进者，而 BRCA1 则通过 HR 进行中断修复。
在实验室中，DSB形成可由电离辐射（IR）引起。虽然本示例利用高剂量的 4 Gy、1 Gy 和 2 Gy 也创建大量的 DSB，适合通过丰富的蛋白质分析叶层形成。需要注意的是，使用的辐射类型和剂量可导致DNA和细胞中不同的病变：虽然IR诱导DSB，它也可能导致单股断裂或碱基修饰（见35，36，,36关于辐照线性能量转移（LET）和DNA损伤类型的参考）。为了确定电离辐射诱导的源（IRIF）形成的动力学及其间隙，表明修复激活的DDR8、9、37、38,9,37,的损伤和反转，在电离辐射后的不同时间点可以监测源层。所有主要DNA损伤蛋白的激活和清除时间已知为39种，许多被调查为关键事件的代理标记。例如，对 ssDNA 具有高亲和力的 pRPA 用作断分切除的代理，MRN 蛋白（MRE11、RAD50、NBS1）和外核酶也可用于评估切除效率。虽然RAD51、BRCA1、BRCA2（乳腺癌2型易感性蛋白）和PALB2（BRCA2的合作伙伴和本地化者）可以监测，以评估人力资源效率，而Ku蛋白或53BP1的存在则用作NHEJ的标记（图1）。
当DNA修复机械的蛋白质相互招募到超级复合物中分离和组装时，DNA蛋白和蛋白质-蛋白质的相互作用可以通过跟踪它们各自的定位并分析蛋白质的共同定位来推断，如细胞40、41、42,41,42中的重叠信号。在细胞系中，通过基因组编辑或对质粒突变体过度表达，在特定DNA修复基因中引入点突变或删除，允许调查特定残留物及其在识别DNA损伤（例如，与+H2AX）或复杂组装（与其他蛋白质或几种蛋白质共同定位）中可能发挥的作用，以及它们对DNA修复的影响。在这里，我们使用间接免疫荧光作为一种均值，通过跟踪 +2AX foci 来研究 DSB 的形成和分辨率。我们还提出了一个示例，由 DSB 修复的主要参与者进行 foci 形成和共同定位分析：p53 结合蛋白 1 （53BP1）32。如前所述，53BP1 被认为是 DNA 修复路径选择的核心。在 53BP1 积累及其与 +2AX 的共定位后，提供了有关细胞周期相、DNA损伤积累和用于修复 DSB 的路径的宝贵信息。间接免疫定位的目的是评估细胞系DNA损伤修复的效率，如本研究中的IR之后，或在接触细胞中的各种应力后，从DNA交联到复制分叉的阻塞（表1提供了DNA损伤剂列表）。
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/61447/61447fig1v2.jpg"> 图1：DNA双链断裂（DSB）修复途径。 DSB 修复涉及两个主要途径：同源重组（HR、左）和非同源端连接（NHEJ，右）。断裂后，蛋白质被激活以标记断裂（+2AX），参与最终切除（MRN），涂上被切除的ssDNA（pRPA），促进重组（BRCA1，PALB2，BRCA2，RAD51）或限制切除，促进NHEJ（53BP1）。其他蛋白质参与损伤修复，但列出的蛋白质通常遵循间接免疫荧光。 <a href="https://www.jove.com/files/ftp_upload/61447/61447fig1v2large.jpg" target="_blank">请单击此处查看此图的较大版本。</a>
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always"><tbody>
<tr>
<td>DNA损伤剂</td>
			<td>行动机制</td>
			<td>推荐剂量</td>
		</tr>
<tr>
<td>• 射线/X 射线</td>
			<td>辐射 形成双链断裂与一些不受控制的细胞效应</td>
			<td>1-4 Gy</td>
		</tr>
<tr>
<td>
36Ar 离子</td>
			<td>辐射 双链断裂的形成</td>
			<td>270千瓦/μm</td>
		</tr>
<tr>
<td>• 粒子</td>
			<td>辐射 双链断裂的形成</td>
			<td>116 keV/μm</td>
		</tr>
<tr>
<td>博莱 霉 素</td>
			<td>DNA合成的抑制剂</td>
			<td>0.4-2 μg/mL</td>
		</tr>
<tr>
<td>喜 树 碱</td>
			<td>托托莫默酶 I 的抑制剂</td>
			<td>10-200 nM</td>
		</tr>
<tr>
<td>顺 铂</td>
			<td>阿尔基拉特剂 （诱导海峡内部交联）</td>
			<td>0.25-2 μM</td>
		</tr>
<tr>
<td>阿 霉 素</td>
			<td>中间代理 托托莫默酶II.的抑制剂</td>
			<td>10-200 nM</td>
		</tr>
<tr>
<td>埃托波赛德</td>
			<td>托托莫默酶II.的抑制剂</td>
			<td>10 μM</td>
		</tr>
<tr>
<td>羟基尤雷亚</td>
			<td>DNA合成的抑制剂 （由核糖核酸还原酶）</td>
			<td>10-200 μM</td>
		</tr>
<tr>
<td>甲基甲烷硫化甲酸酯</td>
			<td>阿尔基拉特剂</td>
			<td>0.25-2 mM</td>
		</tr>
<tr>
<td>米托米霉素 C</td>
			<td>阿尔基拉特剂</td>
			<td>0.25-2 μM</td>
		</tr>
<tr>
<td>紫外线（UV）光</td>
			<td>甲状腺素二丁的形成 （产生DNA链失真）</td>
			<td>50-100 mJ/厘米2
</td>
		</tr>
</tbody></table>表1：基因毒性剂.DNA损伤剂的例子，其作用机制和根据建议的工作浓度引起的损伤。

<table>
	<tbody>
		<tr>
			<td>16% (v/v) paraformaldehyde (PFA) aqueous solution</td>
			<td>Electron Microscopy Sciences</td>
			<td>15710</td>
			<td>Microscopy quality of the PFA ensures best images. If using &#34;home-made PFA&#34;, filter prior to use.</td>
		</tr>
		<tr>
			<td>Bovine serum albumin (BSA)</td>
			<td>Sigma-Aldrich</td>
			<td>A3059</td>
			<td>Heat-shock fraction is recommended, to avoid precipitation/background.</td>
		</tr>
		<tr>
			<td>Coverglass #1, 18 mm round (coverslips)</td>
			<td>Neuvitro</td>
			<td>NC0308920</td>
			<td>Coverslips need to be cleaned and sterilized prior using, with HCl or ethanol.</td>
		</tr>
		<tr>
			<td>DMEM, High Glucose [(+) 4.5 g/L D-Glucose, (+) L-Glutamine, (-) Sodium Pyruvate]</td>
			<td>Gibco</td>
			<td>11965118</td>
			<td>Adjust the growing media to the needs of cell line used.</td>
		</tr>
		<tr>
			<td>DPBS, no calcium, no magnesium</td>
			<td>Gibco</td>
			<td>14190144</td>
			<td>PBS for tissue culture.</td>
		</tr>
		<tr>
			<td>Ethylene glycol-bis(&#946;-aminoethyl ether)-N,N,N&#8242;,N&#8242;-tetraacetic acid (EGTA)</td>
			<td>Research Products International</td>
			<td>E57060</td>
			<td>Nuclear extraction buffer.</td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum (FBS)</td>
			<td>Life Technologies</td>
			<td>104370028</td>
			<td>The quality of FBS can be assessed by testing gH2AX foci formation. If traces of genotoxic endotoxin are present in the batch, gH2AX will be positive in the absence of stress.</td>
		</tr>
		<tr>
			<td>Magnesium chloride (MgCl2)</td>
			<td>Research Products International</td>
			<td>M24000</td>
			<td>Nuclear extraction buffer.</td>
		</tr>
		<tr>
			<td>Piperazine-N,N&#8242;-bis(2-ethanesulfonic acid) (PIPES)</td>
			<td>Research Products International</td>
			<td>P40150</td>
			<td>Nuclear extraction buffer.</td>
		</tr>
		<tr>
			<td>SlowFade Diamond Antifade Mountant with DAPI</td>
			<td>Invitrogen</td>
			<td>S36973</td>
			<td>300 nM DAPI with VECTASHIELD Antifade Mounting Medium can be used instead.</td>
		</tr>
		<tr>
			<td>Sodium chloride (NaCl)</td>
			<td>Research Products International</td>
			<td>S23020</td>
			<td>Nuclear extraction buffer.</td>
		</tr>
		<tr>
			<td>Sucrose</td>
			<td>Research Products International</td>
			<td>S24060</td>
			<td>Nuclear extraction buffer.</td>
		</tr>
		<tr>
			<td>Superfrost Plus Microscope Slides</td>
			<td>Fisherbrand</td>
			<td>1255015</td>
			<td>Polysine Slides can be used instead.</td>
		</tr>
		<tr>
			<td>TC-Treated Multiple Well Plates, size 12 wells</td>
			<td>Costar</td>
			<td>3513</td>
			<td>Seeding on coverslips is done in 12-wells plate.</td>
		</tr>
		<tr>
			<td>Triton X-100</td>
			<td>AmericanBio</td>
			<td>AB02025</td>
			<td>Nuclear extraction buffer.</td>
		</tr>
		<tr>
			<td>TrypLE Express Enzyme (1X), No Phenol Red</td>
			<td>Gibco</td>
			<td>12604021</td>
			<td>Trypsin-EDTA can be used instead.</td>
		</tr>
		<tr>
			<td>Trypsin-EDTA (0.5%), No Phenol Red</td>
			<td>Gibco</td>
			<td>15400054</td>
			<td>TrypLE can be used instead.</td>
		</tr>
	</tbody>
</table>

visualization of dna repair proteins interaction by immunofluorescence

哺乳动物细胞经常暴露在化学物质、辐射和自然产生的代谢产物中，这些产物会造成特定类型的DNA侮辱。基因毒性剂可以破坏DNA骨干，破坏它，或修改单个碱基的化学性质。在DNA侮辱之后，DNA损伤反应（DDR）途径被激活，参与修复的蛋白质被招募。在感知损坏类型和激活适当的维修响应时，涉及大量因素。未能正确激活和招募 DDR 因子可能导致基因组不稳定，这是包括癌症在内的许多人类疾病的基础。DDR蛋白的研究可以提供对基因毒性药物反应和细胞耐药性机制的见解。
体内蛋白质可视化有两 种主要方法：直接观察，通过用荧光蛋白标记感兴趣的蛋白质，然后通过活体成像或固定样品上的间接免疫荧光跟踪。虽然荧光标记蛋白质的可视化允许随着时间的推移进行精确监测，但 N-或 C-术语中的直接标记可能会干扰蛋白质的定位或功能。观察蛋白质的未修改，内源版本是首选。当DNA修复蛋白被招募到DNA侮辱中时，它们的浓度会局部增加，它们形成组，或"foci"，这些组可以通过使用特异性抗体的间接免疫荧光来可视化。
虽然蛋白质叶酸的检测不能提供直接相互作用的明确证据，但细胞中蛋白质的共同定位表明它们重新组合到损伤发生地，并可以告知复杂形成所需的事件序列。仔细分析表达野生类型或蛋白质突变版本的细胞的 foci 空间重叠，可以为对 DNA 修复功能重要的功能域提供宝贵的线索。最后，蛋白质的共同定位表明可能的直接相互作用，可以通过细胞中的共免疫沉淀或使用纯化蛋白质直接下拉来验证。

第2天，或24小时后种子细胞在盖玻片上，细胞经历了一个分裂，是80%的汇合。DNA修复蛋白中特定的击倒或突变可以增加加倍的时间，或使细胞对基因毒性治疗敏感，种子密度以及治疗剂量应相应调整。为了确定最佳工作条件，随着时间的推移，西方的αH2AX的印迹可以确定DNA损伤反应的时间，并且可以通过菌落形成测定来确定对辐照的敏感性。
未经过辐照处理的细胞（如果有?...

Watch this Scientific Journal Video about Visualization of DNA Repair Proteins Interaction by Immunofluorescence at JoVE.com

Visualization of DNA Repair Proteins Interaction by Immunofluorescence

在DNA损伤之后，人类细胞激活必要的修复途径，以恢复其基因组的完整性。在这里，我们描述了间接免疫荧光的方法，作为检测DNA修复蛋白，分析其空间和时间招募，并帮助查询DNA损伤点蛋白质-蛋白质相互作用的方法。

免疫荧光DNA修复蛋白相互作用的可视化

Mammalian cells are constantly exposed to chemicals, radiations, and naturally occurring metabolic by-products, which create specific types of DNA ...

间接免疫荧光使得检测DNA修复蛋白成为可能，空间和时间招募的照片，它有助于在DNA损伤现场查询蛋白蛋白相互作用。DNA损伤后，DNA修复蛋白被招募到DNA侮辱，而它们的浓度增加本地，他们形成组称为foci，可以通过间接免疫荧光在固定样品上可视化。这种技术可用于检测蛋白质来源，以及量化细胞中存在的细胞的结肠化。这可以帮助解释复杂地层和DNA修复所需的事件序列。特定的蛋白蛋白相互作用可以从这些实验中得到。演示程序将是芭芭拉德拉佩纳，一个非常有才华的博士后照片从我的实验室开始，通过成长4万个希拉细胞在每个超过12井板与18毫米圆形玻璃盖玻片到80%的汇合。将细胞暴露在四个灰色伽马照射下后，用一毫升 PBS 洗涤两次。然后完全取出PBS，向每井添加200微升的NDB。在室温下孵育细胞两分钟，然后取出NDB。请记住，孵育时间可能因细胞系而异，但通常不应超过两分钟。用一毫升PBS清洗细胞。然后完全取出PBS，将200微升4%PFA添加到每井中，用于细胞固定。在4摄氏度下孵育细胞10分钟。然后取出PFA，向每一井添加一毫升PBS。完全去除PBS，然后向每井添加200微升的阻消溶液，并在室温下孵育细胞2小时，或在4摄氏度下孵育16至18小时。稀释原抗体和稀释缓冲液，并涡流，直到很好地混合在湿度箱中，在这里一片副膜，并在一滴中加入10微升原抗体。将盖玻片的一个边缘与水滴对齐，然后慢慢将其降到铺开液体的副膜上。在室温下孵育盖玻片两小时。孵育后，盖子在PBS中滑动三次，每次洗涤一分钟。稀释二次抗体和稀释缓冲液，并旋转它，直到混合良好，将10微升的二次抗体应用到每个盖玻片上，如前所述，并在室温下孵育两小时，防止光线。用 PBS 清洗盖滑三次，每次洗水一次。然后用含 DAPI 密封盖的基于甘油的安装介质将它们安装到玻璃幻灯片上，并用透明指甲油进行干燥 20 分钟。将浸入油滴放在 60 x 客观透镜上，并使用 DAPI 通过目镜定位核以进行 XYZ 图像采集，打开采集软件，将扫描仪类型设置为扫描器类型，将扫描仪类型设置为圆形和 512 x 512 图像大小。在 PMT 面板模式下设置为 VBM 平均值到帧，顺序扫描到线。接下来设置染料和热探测器设置通道一到DAPI和SD一，通道二到亚历克萨弗488和HSD三，通道三到亚历克萨弗在647和HSD四选择到Z.To调整实时图像，按下实时窗口的实时按钮，并调整焦点。然后使用 PMT 工具窗口设置激光强度灵敏度、增益和偏移 z 堆栈，选择"开始到结束"和"15 片"。选择该文件夹以保存图像，然后按 LSM 开始按钮开始获取。完成后，按完成序列按钮以完成图像采集。打开分析软件，然后按批处理工具窗口，然后选择要分析的图像。转到分析工具窗口并选择投影，该投影将显示 15 个切片的最大强度投影。在输入输出设置下，选择创建的批处理和输出文件夹。按要处理的图像的过程，然后将图像导出为 TIFF 文件。根据手稿指示使用细胞增版进行核定量。未经过辐射处理的细胞很少出现伽马H2AX博览标志。在缺乏必要的DNA修复蛋白的情况下，可以在DNA断裂时观察到伽马H2AX的积累。未修复的断裂的积累可能导致细胞成为由固体伽马H2AX核指示的前期低度。辐照后，核表现出大量的双搁浅断裂，伽马H2AX的局部性非常迅速。如果没有辐射，很少观察到任何 foci，但辐射后一二四和十六小时以及 NOA 辐射控制方面，对 foci 的数量进行量化。根据提出的生物学问题和所需的数据类型，应考虑通过不同动物物种中提出的多路复用初级抗体和使用二级抗体来研究同分体化，并标有不同的荧光团。绿色和红色的叠加，产生黄色热点，感兴趣的两种蛋白质都存在于相同的像素中。科洛化的定量分析可以通过基于对象的方法或执行强度相关系数分析的统计方法实现。在不同动物物种中产生的主要抗体的组合，可用于此协议。确保抗体是相容的，不会相互干扰。您需要适当地设置用于针对每个初级抗体的二级抗体，并在选择要使用的较少力时考虑特定的光谱重叠。结肠化或蛋白质表示可能的直接相互作用。这可以通过细胞中的颗粒沉淀来验证，或者直接使用体外纯化蛋白质进行分解。

Research

JoVE Journal

Biology

Genetic Studies of Human DNA Repair Proteins Using Yeast as a Model System 

人类DNA修复蛋白的遗传研究利用酵母作为模型系统

Understanding the roles of human DNA repair proteins in genetic pathways is a formidable challenge to many researchers.  Genetic studies in mammalian ...

科研

生物学

Imaging Mismatch Repair and Cellular Responses to DNA Damage in Bacillus subtilis

Imaging Mismatch Repair and Cellular Responses to DNA Damage in Bacillus subtilis

成像错配修复和DNA损伤的细胞反应枯草芽孢杆菌</em

Both prokaryotes and eukaryotes respond to DNA damage through a complex set of physiological changes. Alterations in gene expression, the redistribution ...

Analysis of DNA Double-strand Break (DSB) Repair in Mammalian Cells

Analysis of DNA Double-strand Break DSB Repair in Mammalian Cells

在哺乳动物细胞中的DNA双链断裂（DSB）的维修分析

DNA double-strand breaks are the most dangerous DNA lesions that may lead to massive loss of genetic information and cell death.  Cells repair DSBs using ...

Visualization of MG53-mediated Cell Membrane Repair Using in vivo and in vitro Systems

Visualization of MG53-mediated Cell Membrane Repair Using in vivo and in vitro Systems

MG53介导的细胞膜使用维修的可视化在体内在体外系统

Repair of acute injury to the cell membrane is an elemental process of normal cellular physiology, and defective membrane repair has been linked to many ...

Visualization of DNA Replication in the Vertebrate Model System DT40 using the DNA Fiber Technique

使用可视化的DNA复制DNA纤维的技术，在脊椎动物的模型系统DT40

Maintenance of replication fork stability is of utmost importance for dividing cells to preserve viability and prevent disease. The processes involved not ...

gDNA Enrichment by a Transposase-based Technology for NGS Analysis of the Whole Sequence of BRCA1, BRCA2, and 9 Genes Involved in DNA Damage Repair

gDNA Enrichment by a Transposase-based Technology for NGS Analysis of the Whole Sequence of BRCA1, BRCA2, and 9 Genes Involved in DNA Damage Repair

基因组DNA富集转座为基础的技术的整个序列的农工商分析<em&gt; BRCA1基因</em&gt;<em&gt; BRCA2</em&gt;和9个基因参与DNA损伤修复

The widespread use of Next Generation Sequencing has opened up new avenues for cancer research and diagnosis. NGS will bring huge amounts of new data on ...

Visualization of miniSOG Tagged DNA Repair Proteins in Combination with Electron Spectroscopic Imaging (ESI)

Visualization of miniSOG Tagged DNA Repair Proteins in Combination with Electron Spectroscopic Imaging ESI

在联合电子能谱成像miniSOG标记的DNA修复蛋白可视化（ESI）

The limits to optical resolution and the challenge of identifying specific protein populations in transmission electron microscopy have been obstacles in ...

Immunofluorescence Analysis of Endogenous and Exogenous Centromere-kinetochore Proteins

内源性的免疫荧光分析及外源着丝粒着丝粒蛋白

"Centromeres" and "kinetochores" refer to the site where chromosomes associate with the spindle during cell division. Direct visualization of ...

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

表面拴DNA大分子的可视化与荧光蛋白的DNA结合肽

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

Visualization of DNA Compaction in Cyanobacteria by High-voltage Cryo-electron Tomography

高压低温电子层析成像对蓝藻 DNA 压实的可视化研究

This protocol describes how to visualize the transient DNA compaction in cyanobacteria. DNA compaction is a dramatic cytoplasmic event recently found to ...