作者感谢马蒂亚斯彼得和他的小组在生物化学研究所在ETH苏黎世这些方法已被开发的地方。这项工作已经由瑞士国家科学基金会的支持。

1。显微镜测量<ol><li>接种5毫升合成培养基中的酵母。 </li><li>细胞生长于30℃过夜。 </li><li>测量过夜培养物的OD 600，第二天早上。 </li><li>稀释过夜培养在5毫升合成培养基，以OD 600 0.05。 </li><li>生长的稀释的培养在30℃下为至少4小时。 </li><li>制备3倍浓缩在合成培养基（0.6 M）的NaCl溶液。 </li><li>准备1毫克/毫升的溶液刀豆蛋白A（刀豆）的PBS中。 </li><li>滤液〜200微升的溶液刀豆入井幻灯片。 </li><li>静置30分钟。 </li><li>删除刀豆解决方案。 </li><li>加入150μlH 2 O至井。 </li><li>除去H 2 O </li><li>测量细胞培养的外径600。 </li><li>在1.5ml微管中制备300μl的细胞培养物在OD 600 = 0.02。 </li><li>超声处理水浴中45秒的单元格。 </li><li>涡简要英里crotube。 </li><li>超声处理水浴中45秒的单元格。 </li><li>短暂涡旋微管。 </li><li>加入200μl细胞培养的好。 </li><li>等待30分钟，以让细胞沉降到井的底部。 </li><li>放置在显微镜的良好滑动。 </li><li>选择照明设置的荧光信道进行记录。 </li><li>选择两个亮场图像的照明设置（一个关注的焦点：3微米以下的焦平面以允许细胞的适当分割）。 </li><li>选择的时间间隔的延时测量</li><li>选择视图图像的字段。 </li><li>开始采集数帧。 </li><li>暂停收购以添加100微升0.6 M氯化钠介质。 </li><li>恢复成像。 </li></ol> 2。流式细胞仪测量<ol><li>接种5毫升合成培养基中的酵母。 </li><li>生长于30℃过夜。 </li><li>措施外径600过夜培养的第二天早晨。 </li><li>稀释过夜培养在5毫升合成培养基，以OD 600 0.1。 </li><li>生长在30℃至少4小时到达外径600 0.2-0.4。 </li><li>准备在H 2 O放线菌酮溶液1毫克/毫升</li><li>制备3倍浓缩在合成培养基（0.6 M）的NaCl溶液。 </li><li>制备1 1.5mL微管加入100μl的0.6M的NaCl的培养基中对每个时间点进行测量。 </li><li>在时间0，加入200μl细胞培养到每个微管。 </li><li>孵育振荡在30℃下</li><li>在时间T，加入30微升放线菌酮的微管。 </li><li>对于所有想要的时间点重复步骤2.11。 </li><li>所有孵育微管至少45分钟，最多3个小时，在30℃振荡。 </li><li>准备FACS管400微升PBS。 </li><li>超声处理的细胞在水浴中1分钟。 </li><li>短暂涡旋微管。 </li><li>儿子icate细胞在水浴中放置1分钟。 </li><li>短暂涡旋微管。 </li><li>加入100μl细胞培养在每个微管到其相应的FACS管。 </li><li>选择488 nm激发激光和三十〇分之五百三nm的带通滤波器进行检测。 </li><li>测试非表达，充分表达样品，以确认他们是否落在探测器的灵敏度范围。 </li><li>测量10,000个细胞的每个样品。 </li></ol>

<ol>
	<li>Gasch, A. P., Spellman, P. T., 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=Genomic+expression+programs+in+the+response+of+yeast+cells+to+environmental+changes.">Genomic expression programs in the response of yeast cells to environmental changes.</a> Molecular biology of the cell. 11 (12), 4241-4257 (2000).</li><li>de Nadal, E., Zapater, M., Alepuz, P. M., Sumoy, L., Mas, G., Posas, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+MAPK+Hog1+recruits+Rpd3+histone+deacetylase+to+activate+osmoresponsive+genes.">The MAPK Hog1 recruits Rpd3 histone deacetylase to activate osmoresponsive genes.</a> Nature. 427 (6972), 370-374 (2004).</li><li>Ghaemmaghami, S., Huh, W. -. 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B., Levine, A. J., Siggia, E. D., Swain, P. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stochastic+gene+expression+in+a+single+cell.">Stochastic gene expression in a single cell.</a> Science. 297 (5584), 1183-1186 (2002).</li><li>Pelet, S., Dechant, R., Lee, S. S., van Drogen, F., Peter, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+integrated+image+analysis+platform+to+quantify+signal+transduction+in+single+cells.">An integrated image analysis platform to quantify signal transduction in single cells.</a> Integrative biology : quantitative biosciences from nano to macro. 4 (10), 1274-1282 (2012).</li><li>Carpenter, A. E., Jones, T. R., 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=CellProfiler:+image+analysis+software+for+identifying+and+quantifying+cell+phenotypes.">CellProfiler: image analysis software for identifying and quantifying cell phenotypes.</a> Genome biology. 7 (10), R100 (2006).</li><li>Chernomoretz, A., Bush, A., Yu, R., Gordon, A., Colman-Lerner, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Using+Cell-ID+1.4+with+R+for+microscope-based+cytometry.">Using Cell-ID 1.4 with R for microscope-based cytometry.</a> Current protocols in molecular biology. Chapter 14, Unit 14.18 (2008).</li><li>Dimopoulos, S., Mayer, C., Rudolf, F., Stelling, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Automatic+Single+Cell+Segmentation+in+a+Variety+of+Microscopy+Images.">Automatic Single Cell Segmentation in a Variety of Microscopy Images.</a> Current protocols in molecular biology. , (2012).</li><li>Miyawaki, A., Nagai, T., Mizuno, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanisms+of+protein+fluorophore+formation+and+engineering.">Mechanisms of protein fluorophore formation and engineering.</a> Current Opinion in Chemical Biology. 7 (5), 557-562 (2003).</li><li>Hersen, P., McClean, M. 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作者宣称，他们有没有竞争的财务权益。

显微镜井经ConA的治疗是一个重要的步骤，以确保电池的正确成像。因为刀豆具有低溶解度的在PBS中的（5毫克/毫升）中，过滤过程可以去除大的聚集体存在于未过滤溶液，并干扰成像。细胞相对强烈地附着到被处理的表面和在加入诱导溶液不应妨碍细胞的定位，从而允许连续跟踪之前和之后的刺激。这个处理也可以应用到流动通道或微流体装置进行的细胞进行的恒定流量7,15...

通过转导级联信号常常达到高潮蛋白的表达。这种表达谱中的表征对于理解生物学途径的功能的关键因素。上调的蛋白及其活化的动态频谱的识别可以通过例如微阵列，RNA印迹或蛋白质印迹1-3的各种技术来实现。然而，这些技术平均细胞的全体人民的响应。了解蛋白质的表达的精细调节，理想的是收集的测量在单细胞水平。理想情况下，这些测量还应提供定量数据服从发展的基本途径的数学模型。 显微镜和流式细胞仪两种技术，这是非常适合提供这样的定量单细胞测量。蛋白质与荧光蛋白质的内源性标记可以bÉ用来量化其4表达水平。然而，由于在该蛋白质的末端增加了一个大的荧光部分可以使其不起作用的，它往往是更可取的，以产生根据一个启动子驱动的荧光构建体的表达特异性表达记者。此报告蛋白是外生给蜂窝系统，因此不影响正在发生在细胞内信号转导事件。 既显微镜和流式细胞仪已经被广泛应用于酵母的信令字段。作为例子;科尔曼-雷纳和同事相关的，在单个细胞中，配合特定的和组成性表达，记者通过显微镜来量化在酵母交配信号转导级联5的噪声的表达，阿贾尔和使用流式细胞仪来研究调控网络的同事控制的GAL基因6的表达。在先前的研究7，我们已经使用了一个化合物-关于这两种技术从高渗透压甘油（HOG）途径在芽殖酵母研究的表达输出。这有丝分裂原激活的蛋白激酶（MAPK）途径是由超渗透胁迫触发。它导致MAPK Hog1，这转位到细胞的核的活化，诱导产生大约300个基因的表达的转录程序。为了研究这个过程，我们设计了一个基于该STL1启动子（响应Hog1活动8特异性诱导基因）驾驶一辆四金星荧光蛋白（P STL1-QV）的表达表达记者。流式细胞术测量露天细胞的两个群体的存在下，在中间应力水平（0.1M NaCl）中以表达荧光报道人口的一小部分。我们用显微镜来进一步研究这个问题，并发现这种噪声的蛋白质表达，内在因素9管辖。我们凑LD进一步观察到细胞Hog1活动的一个类似的水平可能显示明显不同的表达效果。这两种技术的结合允许我们来演示如何的应激反应基因的慢重塑的影响表达产物在单细胞水平7。 在本文中，我们使用p STL1-QV记者通过超渗透休克诱导如通过显微镜蛋白表达的定量的一个例子中的表达和流式细胞术。一脉相承受到0.2M的NaCl胁迫，研究了这两种技术。这将允许我们强调在这两个高度互补的技术，一些关键的差别。

<table border="1">
		<tbody>
		 <tr>
			 <td></td>
			 <td></td>
			 <td></td>
			 <td>Reagent</td>
		 </tr>
		 <tr>
			 <td>Yeast Nitrogen Base</td>
			 <td>ForMedium</td>
			 <td>CYN6202</td>
			 <td></td>
		 </tr>
		 <tr>
			 <td>CSM amino-acid mix</td>
			 <td>ForMedium</td>
			 <td>DCS0011</td>
			 <td></td>
		 </tr>
		 <tr>
			 <td>Concanavalin A</td>
			 <td>GE Healthcare</td>
			 <td>17-0450-01</td>
			 <td></td>
		 </tr>
		 <tr>
			 <td>Cycloheximide</td>
			 <td>Fluka Aldrich Sigma</td>
			 <td>C7698</td>
			 <td>Toxic</td>
		 </tr>
		 <tr>
			 <td>ySP9</td>
			 <td></td>
			 <td></td>
			 <td>W303Mata leu2::LEU2-pSTL1-quadrupleV enus</td>
		 </tr>
		 <tr>
			 <td>pSP34</td>
			 <td></td>
			 <td></td>
			 <td>pRS305 pSTL1 (-800 -0) - quadruple V enus</td>
		 </tr>
		 <tr>
			 <td></td>
			 <td></td>
			 <td></td>
			 <td>Material</td>
		 </tr>
		 <tr>
			 <td>Microscope</td>
			 <td>Nikon</td>
			 <td>Ti-Eclipse</td>
			 <td></td>
		 </tr>
		 <tr>
			 <td>Microscope control software</td>
			 <td>Micro-manager</td>
			 <td>Ver 1.4.11</td>
			 <td></td>
		 </tr>
		 <tr>
			 <td>Incubation chamber</td>
			 <td>LIS</td>
			 <td>The Box</td>
			 <td></td>
		 </tr>
		 <tr>
			 <td>Fluorescence light source</td>
			 <td>Lumencor</td>
			 <td>SpectraX</td>
			 <td></td>
		 </tr>
		 <tr>
			 <td>Camera</td>
			 <td>Hamamatsu</td>
			 <td>Flash 4.0</td>
			 <td></td>
		 </tr>
		 <tr>
			 <td>Flow cytometer</td>
			 <td>BD</td>
			 <td>FACS calibur</td>
			 <td></td>
		 </tr>
		 <tr>
			 <td>Sonicator bath</td>
			 <td>Telesonic</td>
			 <td>TUC-150</td>
			 <td></td>
		 </tr>
		 <tr>
			 <td>8-well-slide </td>
			 <td>Thermo Lab-tek</td>
			 <td>155409</td>
			 <td></td>
		 </tr>
		 <tr>
			 <td>96-well-plate</td>
			 <td>Matrical bioscience</td>
			 <td>MGB096-1-2-LG</td>
			 <td></td>
		 </tr>
		 <tr>
			 <td>FACS tube</td>
			 <td>BD Falcon</td>
			 <td>352054</td>
			 <td></td>
		 </tr>
		</tbody>
 </table>

temporal quantification of mapk induced expression in single yeast cells

基因表达在单细胞水平进行定量揭示了掩盖在在群体水平上进行测量，新的监管机制。基于显微镜和流式细胞仪两种方法都表现出这样的数据怎么可以被收购。荧光报道诱导活化时的高渗透压甘油MAPK途径在酵母中的表达被用来作为一个例子。每种方法的具体优点突出。流式细胞术测量大量细胞（10,000），并提供了直接的措施独立的荧光蛋白的慢动力学成熟的蛋白表达的动力学。通过显微镜活细胞成像是通过对比限于记者在较少的细胞的成熟形式的测量。然而，通过这种技术产生的数据集可以是非常丰富得益于多个记者的组合，以及在空间和时间信息从单个细胞中获得。这两种测量方法的结合，可以通过信号传导通路兑现蛋白表达的调控新的见解。

显微镜酵母细胞轴承表达式记者p STL1-QV（ySP9 7）被附连到良好的滑动件的底部并在显微镜下放置。将细胞通过加入应力介质的成像会话的过程中刺激直接进入井。这使我们能够通路诱导前获得细胞的一些图片，并按照他们的命运刺激后。在本案中，随访细胞为〜2小时，以10分钟的时间间隔。 图1A是诱导和图1B前非荧光的细胞的图像显示2小...

Watch this Scientific Journal Video about Temporal Quantification of MAPK Induced Expression in Single Yeast Cells at JoVE.com

Temporal Quantification of MAPK Induced Expression in Single Yeast Cells

基于流式细胞术和显微术的两个互补的方法给出，使定量基因表达的诱导通过MAPK途径在酵母的激活的动力学，在单细胞水平。

在单酵母细胞MAPK诱导表达的时空定量

The quantification of gene expression at the  single cell level uncovers novel regulatory mechanisms obscured in measurements  performed at the population ...

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Biology

8.4K 次观看.  University of Lausanne. 基于流式细胞术和显微术的两个互补的方法给出，使定量基因表达的诱导通过MAPK途径在酵母的激活的动力学，在单细胞水平。 

视频: Temporal Quantification of MAPK Induced Expression in Single Yeast Cells

Vaccinia Virus Infection &amp; Temporal Analysis of Virus Gene Expression: Part 1

The family Poxviridae consists of large double-stranded DNA containing viruses that replicate exclusively in the cytoplasm of infected cells. Members of the orthopox genus include variola, the causative agent of human small pox, monkeypox, and vaccinia (VAC), the prototypic member of the virus family. Within the relatively large (~ 200 kb) vaccinia genome, three classes of genes are encoded: early, intermediate, and late. While all three classes are transcribed by virally-encoded RNA polymerases, each class serves a different function in the life cycle of the virus. Poxviruses utilize multiple strategies for modulation of the host cellular environment during infection. In order to understand regulation of both host and virus gene expression, we have utilized genome-wide approaches to analyze transcript abundance from both virus and host cells. Here, we demonstrate time course infections of HeLa cells with Vaccinia virus and sampling RNA at several time points post-infection. Both host and viral total RNA is isolated and amplified for hybridization to microarrays for analysis of gene expression.

Protocol for Vaccinia infection of HeLa cells and analysis of host and viral gene expression. Part 1 of 3.

牛痘病毒感染及病毒基因表达的时空分析：第1部分

The family Poxviridae consists of large double-stranded DNA containing viruses that replicate exclusively in the cytoplasm of infected cells.  Members of ...

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生物学

Vaccinia Virus Infection &amp; Temporal Analysis of Virus Gene Expression: Part 2

The family Poxviridae consists of large double-stranded DNA containing viruses that replicate exclusively in the cytoplasm of infected cells. Members of the orthopox genus include variola, the causative agent of human small pox, monkeypox, and vaccinia (VAC), the prototypic member of the virus family. Within the relatively large (~ 200 kb) vaccinia genome, three classes of genes are encoded: early, intermediate, and late. While all three classes are transcribed by virally-encoded RNA polymerases, each class serves a different function in the life cycle of the virus. Poxviruses utilize multiple strategies for modulation of the host cellular environment during infection. In order to understand regulation of both host and virus gene expression, we have utilized genome-wide approaches to analyze transcript abundance from both virus and host cells. Here, we demonstrate time course infections of HeLa cells with Vaccinia virus and sampling RNA at several time points post-infection. Both host and viral total RNA is isolated and amplified for hybridization to microarrays for analysis of gene expression.

Protocol for Vaccinia infection of HeLa cells and analysis of host and viral gene expression. Part 2 of 3.

牛痘病毒感染及病毒基因表达的时空分析：第2部分

Vaccinia Virus Infection &amp; Temporal Analysis of Virus Gene Expression: Part 3

Protocol for Vaccinia infection of HeLa cells and analysis of host and viral gene expression. Part 3 describes the process of fluorescently labeling the amplified RNA from both host and viral samples by amino allyl coupling of dyes. Part 3 of 3.

牛痘病毒感染及病毒基因表达的时空分析：第3部分

Using the Gene Pulser MXcell Electroporation System to Transfect Primary Cells with High Efficiency

It is becoming increasingly apparent that electroporation is the most effective way to introduce plasmid DNA or siRNA into primary cells. The Gene Pulser MXcell electroporation system and Gene Pulser electroporation buffer (Bio-Rad) were specifically developed to easily transfect nucleic acids into mammalian cells and difficult-to-transfect cells, such as primary and stem cells. We will demonstrate how to perform a simple experiment to quickly identify the best electroporation conditions. We will demonstrate how to run several samples through a range of electroporation conditions so that an experiment can be conducted at the same time as optimization is performed. We will also show how optimal conditions identified using 96-well electroporation plates can be used with standard electroporation cuvettes, facilitating the switch from electroporation plates to electroporation cuvettes while maintaining the same electroporation efficiency. In the video, we will also discuss some of the key factors that can lead to the success or failure of electroporation experiments.

This procedure shows how to use the Gene Pulser MXcell electroporation system to rapidly and easily identify the best electroporation conditions for mouse embryonic fibroblasts (MEFs) or other primary cells. Considerations for troubleshooting are also discussed in the associated video.

使用基因脉冲MXcell电穿孔系统主细胞的转染效率高

It is becoming increasingly apparent that electroporation is the most effective way to introduce plasmid DNA or siRNA into primary cells. The Gene Pulser ...

Expression of Recombinant Proteins in the Methylotrophic Yeast Pichia pastoris

Protein expression in the microbial eukaryotic host Pichia pastoris offers the possibility to generate high amounts of recombinant protein in a fast and easy to use expression system.
As a single-celled microorganism P. pastoris is easy to manipulate and grows rapidly on inexpensive media at high cell densities. Being a eukaryote, P. pastoris is able to perform many of the post-translational modifications performed by higher eukaryotic cells and the obtained recombinant proteins undergo protein folding, proteolytic processing, disulfide bond formation and glycosylation [1].
As a methylotrophic yeast P. pastoris is capable of metabolizing methanol as its sole carbon source. The strong promoter for alcohol oxidase, AOX1, is tightly regulated and induced by methanol and it is used for the expression of the gene of interest. Accordingly, the expression of the foreign protein can be induced by adding methanol to the growth medium [2; 3].
Another important advantage is the secretion of the recombinant protein into the growth medium, using a signal sequence to target the foreign protein to the secretory pathway of P. pastoris. With only low levels of endogenous protein secreted to the media by the yeast itself and no added proteins to the media, a heterologous protein builds the majority of the total protein in the medium and facilitates following protein purification steps [3; 4].
The vector used here (pPICZ&alpha;A) contains the AOX1 promoter for tightly regulated, methanol-induced expression of the gene of interest; the &alpha;-factor secretion signal for secretion of the recombinant protein, a Zeocin resistance gene for selection in both E. coli and Pichia and a C-terminal peptide containing the c-myc epitope and a polyhistidine (6xHis) tag for detection and purification of a recombinant protein. We also show western blot analysis of the recombinant protein using the specific Anti-myc-HRP antibody recognizing the c-myc epitope on the parent vector.

Expression of Recombinant Proteins in the Methylotrophic Yeast Pichia pastoris

The protocol describes protein expression using the methylotrophic yeast Pichia pastoris. The preparation of electrocompetent yeast cells, transformation of the vector with the gene of interest into P. pastoris and yeast DNA purification are also performed. Western blot analysis and protein purification build the last steps in this protein expression protocol.

在甲醇酵母表达的重组蛋白毕赤酵母</em

Protein expression in the microbial eukaryotic host Pichia pastoris offers the possibility to generate high amounts of recombinant protein in a fast and ...

Identification of Growth Inhibition Phenotypes Induced by Expression of Bacterial Type III Effectors in Yeast

Many Gram-negative pathogenic bacteria use a type III secretion system to translocate a suite of effector proteins into the cytosol of host cells. Within the cell, type III effectors subvert host cellular processes to suppress immune responses and promote pathogen growth. Numerous type III effectors of plant and animal bacterial pathogens have been identified to date, yet only a few of them are well characterized. Understanding the functions of these effectors has been undermined by a combination of functional redundancy in the effector repertoire of a given bacterial strain, the subtle effects that they may exert to increase virulence, roles that are possibly specific to certain infection stages, and difficulties in genetically manipulating certain pathogens. Expression of type III effectors in the budding yeast Saccharomyces cerevisiae may allow circumventing these limitations and aid to the functional characterization of effector proteins. Because type III effectors often target cellular processes that are conserved between yeast and other eukaryotes, their expression in yeast may result in growth inhibition phenotypes that can be exploited to elucidate effector functions and targets. Additional advantages to using yeast for functional studies of bacterial effectors include their genetic tractability, information on predicted functions of the vast majority of their ORFs, and availability of numerous tools and resources for both genome-wide and small-scale experiments. Here we discuss critical factors for designing a yeast system for the expression of bacterial type III effector proteins. These include an appropriate promoter for driving expression of the effector gene(s) of interest, the copy number of the effector gene, the epitope tag used to verify protein expression, and the yeast strain. We present procedures to induce expression of effectors in yeast and to verify their expression by immunoblotting. In addition, we describe a spotting assay on agar plates for the identification of effector-induced growth inhibition phenotypes. The use of this protocol may be extended to the study of pathogenicity factors delivered into the host cell by any pathogen and translocation mechanism.

In this video, we describe a procedure for the expression of bacterial type III effectors in yeast and the identification of effector-induced growth inhibition phenotypes. Such phenotypes can be subsequently exploited to elucidate effector functions and targets.

细菌III型效应，在酵母中的表达诱导的生长抑制的表型鉴定

Many Gram-negative pathogenic bacteria use a type III secretion system to translocate a suite of effector proteins into the cytosol of host cells. Within ...

Using an Automated Cell Counter to Simplify Gene Expression Studies: siRNA Knockdown of IL-4 Dependent Gene Expression in Namalwa Cells

The use of siRNA mediated gene knockdown is continuing to be an important tool in studies of gene expression.  siRNA studies are being conducted not only to study the effects of downregulating single genes, but also to interrogate signaling pathways and other complex interaction networks.  These pathway analyses require both the use of relevant cellular models and methods that cause less perturbation to the cellular physiology.  Electroporation is increasingly being used as an effective way to introduce siRNA and other nucleic acids into difficult to transfect cell lines and primary cells without altering the signaling pathway under investigation. There are multiple critical steps to a successful siRNA experiment, and there are ways to simplify the work while improving the data quality at several experimental stages.  To help you get started with your siRNA mediated gene knockdown project, we will demonstrate how to perform a pathway study complete from collecting and counting the cells prior to electroporation through post transfection real-time PCR gene expression analysis.  The following study investigates the role of the transcriptional activator STAT6 in IL-4 dependent gene expression of CCL17 in a Burkitt lymphoma cell line (Namalwa).  The techniques demonstrated are useful for a wide range of siRNA-based experiments on both adherent and suspension cells.  We will also show how to streamline cell counting with the TC10 automated cell counter, how to electroporate multiple samples simultaneously using the MXcell electroporation system, and how to simultaneously assess RNA quality and quantity with the Experion automated electrophoresis system.

This procedure describes a quick and easy workflow to introduce siRNA into difficult to transfect cell lines and follow gene expression by real-time PCR. Use of an automated cell counter, multi-well electroporation plate, and automated electrophoresis station provide quick and reliable results without the need for expensive robotic handling.

使用自动细胞计数器简化基因表达研究：在Namalwa细胞的IL - 4依赖的基因表达的siRNA击倒

The use of siRNA mediated gene knockdown is continuing to be an important tool in studies of gene expression.  siRNA studies are being conducted not only ...

Analysis of Global RNA Synthesis at the Single Cell Level following Hypoxia

Hypoxia or lowering of the oxygen availability is involved in many physiological and pathological processes. At the molecular level, cells initiate a particular transcriptional program in order to mount an appropriate and coordinated cellular response. The cell possesses several oxygen sensor enzymes that require molecular oxygen as cofactor for their activity. These range from prolyl-hydroxylases to histone demethylases. The majority of studies analyzing cellular responses to hypoxia are based on cellular populations and average studies, and as such single cell analysis of hypoxic cells are seldom performed. Here we describe a method of analysis of global RNA synthesis at the single cell level in hypoxia by using Click-iT RNA imaging kits in an oxygen controlled workstation, followed by microscopy analysis and quantification.&nbsp; Using cancer cells exposed to hypoxia for different lengths of time, RNA is labeled and measured in each cell. This analysis allows the visualization of temporal and cell-to-cell changes in global RNA synthesis following hypoxic stress.

We describe a technique for analysis of global RNA synthesis in hypoxia using imaging. Click-chemistry labeling of RNA has not previously been performed under hypoxia and allows visualization of global RNA changes at the single cell level. This approach complements the existing averaged RNA techniques, allowing direct visualization of cell-to-cell changes in global RNA synthesis.

全球合成的RNA在单细胞水平以下的低氧分析

Hypoxia or lowering of the oxygen availability is involved in many physiological and pathological processes. At the molecular level, cells initiate a ...

Imaging Spatial Reorganization of a MAPK Signaling Pathway Using the Tobacco Transient Expression System

Visualization of dynamic signaling events in live cells has been a challenge. We expanded an established transient expression system, the biomolecular fluorescent complementation (BiFC) assay in tobacco epidermal cells, from testing protein-protein interaction to monitoring spatial distribution of signal transduction in plant cells. In this protocol, we used the BiFC assay to show that the interaction and the signaling between the Arabidopsis MAPKKK YODA and MAPK6 occur at the plasma membrane. When the scaffold protein BASL was co-expressed, the YODA-MAPK interaction redistributed and spatially co-polarized with CFP-BASL. This modified tobacco expression system allows for quick examination of signaling localization and dynamic changes (less than 4 days) and can accommodate multiple of fluorescent protein colors (at least three). We also presented detailed methods to quantify protein distribution (asymmetric spatial localization, or &#34;polarization&#34;) in tobacco cells. This advanced tobacco expression system has a potential to be used widely for quick testing of dynamic signaling events in live plant cells.

At the subcellular level, signaling events are dynamically modulated by developmental and environmental cues. Here we describe a protocol that employs the tobacco transient expression system to monitor dynamic protein-protein interaction and to disclose spatial organization of signal transduction in plant cells.

成像使用烟草瞬时表达系统MAPK信号通路的空间重组

Visualization of dynamic signaling events in live cells has been a challenge. We expanded an established transient expression system, the biomolecular ...

Using Microfluidic Devices to Measure Lifespan and Cellular Phenotypes in Single Budding Yeast Cells

Budding yeast Saccharomyces cerevisiae is an important model organism in aging research. Genetic studies have revealed many genes with conserved effects on the lifespan across species. However, the molecular causes of aging and death remain elusive. To gain a systematic understanding of the molecular mechanisms underlying yeast aging, we need high-throughput methods to measure lifespan and to quantify various cellular and molecular phenotypes in single cells. Previously, we developed microfluidic devices to track budding yeast mother cells throughout their lifespan while flushing away newborn daughter cells. This article presents a method for preparing microfluidic chips and for setting up microfluidic experiments. Multiple channels can be used to simultaneously track cells under different conditions or from different yeast strains. A typical setup can track hundreds of cells per channel and allow for high-resolution microscope imaging throughout the lifespan of the cells. Our method also allows detailed characterization of the lifespan, molecular markers, cell morphology, and the cell cycle dynamics of single cells. In addition, our microfluidic device is able to trap a significant amount of fresh mother cells that can be identified by downstream image analysis, making it possible to measure the lifespan with higher accuracy.

This article presents a protocol optimized for the production of microfluidic chips and the setup of microfluidic experiments to measure the lifespan and cellular phenotypes of single yeast cells.

使用微流体装置来衡量寿命和细胞表型单芽殖酵母细胞

Budding yeast Saccharomyces cerevisiae is an important model organism in aging research. Genetic studies have revealed many genes with conserved effects ...