<ul><li>启约翰松</li><li>伊万科雷亚</li><li>安德烈亚斯布莱希特</li><li>卡特琳Müentener </li><li>克里斯Noren </li><li>罗的Sun </li><li>徐明</li><li>西奥多戴维斯</li><li>萨尔瓦托雷罗素</li><li>艾华张</li><li>印加戈什</li><li> Elissa Maunus </li><li>尼古拉Labarthe </li><li>詹姆斯麦克法兰</li><li>约翰巴斯韦尔</li><li>布兰达德斯蒙德</li><li>詹姆斯Ellard </li><li>唐梳</li></ul>

电镀CHO - K1细胞： <ol><li> CHO - K1细胞已根据完整的F - 12K6毫升的标准协议胰酶消化新增50 -100μL。 </li><li>移液器向上和向下几次混合细胞悬液，然后分装胰酶消化的细胞悬液300μL1.5硼硅玻璃罩商会（每孔8室无菌实验室TEK二腔盖玻片NALGENE NUNC诠释;产品＃155409;批次：100808-8-0）。 </li><li>在37℃，5％的CO 2过夜孵育样品。 </li></ol>瞬时转染CHO - K1细胞pSNAP ADRB2和pSNAP - H2B： <ol><li>接种前一天看细胞密度和健康检查的细胞培养商会。 </li><li>标签适当数量的离心管。 </li><li>在层流罩，成立转复杂的混合物，根据下面的示例图表，使用或0.3微克pSNAP ADBR2控制质粒DNA pSNAP - H2B控制质粒DNA，1μL的TransPass D2和1μLTransPass V或0.3微克每个反应。 <table border="1" cellspacing="0" cellpadding="0"><tbody><tr><td>质粒</td><td>反应数</td><td> μl的无血清培养基</td><td> μL的TransPass D2 </td><td> μL的TransPass V </td><td> μL的质粒DNA </td><td> μL的TransPass D2/reaction </td><td> μL的TransPass V /反应</td><td> ng的DNA /反应</td><td> DNA的浓度。 （ng /μL的） </td><td> μL的质粒DNA /反应</td></tr><tr><td> SNAP - ADRB2 </td><td> 5 </td><td> 236.5 </td><td> 5 </td><td> 5 </td><td> 3.5 </td><td> 1 </td><td> 1 </td><td> 300 </td><td> 472.34 </td><td> 0.7 </td></tr><tr><td> H2B - SNAP </td><td> 5 </td><td> 237 </td><td> 5 </td><td> 5 </td><td> 3 </td><td> 1 </td><td> 1 </td><td> 300 </td><td> 515.89 </td><td> 0.6 </td></tr><tr><td>嘲笑</td><td> 5 </td><td> 240 </td><td> 5 </td><td> 5 </td><td> 0 </td><td> 1 </td><td> 1 </td><td> 0 </td><td> 0 </td><td> 0 </td></tr><tr><td>未转染</td><td> 5 </td><td> 250 </td><td> 0 </td><td> 0 </td><td> 0 </td><td> 0 </td><td> 0 </td><td> 0 </td><td> 0 </td><td> 0 </td></tr></tbody></table></li><li>首先，混合无血清的F - 12K与相应的质粒DNA，然后添加TransPass D2转染试剂，然后添加TransPass V转染试剂。向上和向下轻轻吹打几次后，每个试剂此外混合组件。 </li><li>在室温下孵育30分钟的反应。 </li><li>在孵化过程中，洗细胞一次，600μL完全DMEM，并添加到每个样品450μL完全DMEM </li><li>将每个样品50μL转染的复杂混合物，缓慢而明智的下拉时尚。 </li><li>孵育的样品在37℃过夜，5％的CO 2。 </li></ol> SNAP细胞的TMR与pSNAP ADRB2和pSNAP - H2B瞬时转染CHO - K1细胞之星标签： <ol><li>小心地从每个样品由真空抽吸转复杂的媒体。 600μL完整的F - 12K和洗涤细胞两次取代，每孔600μL完整的F - 12K的媒体。 </li><li>混合染料标签介质，加入995μL的完整的F - 12K和51μL0.6毫米的SNAP -细胞的TMR明星基板。 SNAP细胞的TMR明星终浓度应采用3mm。移液器向上和向下几次混合后的基板此外。 </li><li>小心取出样品生长介质，每孔加200μL染色标记媒体。在37样本℃，5％CO 2为30分钟。 </li><li>虽然样品孵化，准备为核染色样品混合1μL赫希斯特33342 trihydrochloride，三水（10毫克/毫升溶液中水，16.2 mM的解决方案; Invitrogen公司的分子探针）赫斯特33342解决方案在10毫升的完整的​​F - 12K 。 </li><li>媒体从所有样本中删除，并添加600μL稀赫斯特解决每个样品。在37样本℃，5％CO 2为5分钟。 </li><li>洗净样品600μL完整的F - 12K的三倍。 </li><li>样品在37℃，5％CO2的一个额外的30分钟2，允许非法人的荧光团弥漫的细胞。 </li><li> 30分钟后，媒体上的SNAP -细胞样本最后一次更改，并进行成像。 </li><li>使用蔡司Apotome AXIOVERT 200M荧光显微镜图像的细胞。 </li></ol>代表性的成果<img src="/files/ftp_upload/1876/1876fig1.jpg" alt="图1" /> 图1。使用标准的现场COS - 7细胞表达的SNAP -标签融合的荧光显微镜，荧光成像的一些具有代表性的结果。这第一个图像显示现场COS - 7细胞表达pSNAP - H2B（核组蛋白）标记的SNAP -细胞的TMR明星的。 pSNAP H2B构造生成使用pSNAP标记（M）载体。细胞标记的SNAP -细胞为30分钟（TMR）明星，并用Hoechst 33342（蓝色）counterstained的原子核。粉红色的荧光，表明组蛋白是目前除了蓝色荧光显示细胞核红色荧光的叠加。 H2B蛋白的表达清楚，容易辨识。 <img src="/files/ftp_upload/1876/1876fig2.jpg" alt="图2" /> <img src="/files/ftp_upload/1876/1876fig3.jpg" alt="图3" /> 图2和3。下面两个图像显示现场的COS - 7细胞瞬时转染pSNAP的ADRβ2 。 细胞标记的SNAP -细胞TMR明星（红色），并用Hoechst 33342（蓝色）counterstained。 pSNAPADRβ2构造生成使用pSNAP标记（M）载体。细胞标记的SNAP -细胞为30分钟（TMR）明星，并用Hoechst 33342（蓝色）counterstained的原子核。红色荧光，表明细胞表面的受体蛋白ADRB2的存在，而蓝色荧光标识的核。

<ol>
	<li>Johnsson, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visualizing+biochemical+activities+in+living+cells.">Visualizing biochemical activities in living cells.</a> Nat Chem Biol. 5, 63-65 (2009).</li><li>Johnsson, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=SNAP-tag+Technologies:+Novel+Tools+to+Study+Protein+Function.">SNAP-tag Technologies: Novel Tools to Study Protein Function.</a> NEB Expressions. 3.3, 1-3 (2008).</li></ol>

作者是受聘于New England Biolabs公司，产生了本文中使用的试剂和仪器。

有几个变量的影响，如聚焦，激光强度，设备的能力，所使用的镜头，等的荧光耐光决定之前，必须先褪色捕获如何快速的荧光观察到的结果。 这种蛋白质的标签方法是灵活，适用于许多应用。 SNAP - tag和剪辑标记合成探针的融合蛋白与特定的标签技术，使蛋白质功能的各个方面，包括在活体细胞和细胞裂解液中的各种动态过程，。 SNAP -，夹具，MCP - ACP标签技术提供的简单性和非凡的多功能蛋白质在活细胞和固定细胞成像和蛋白质在体外研究。建立一个单一的基因构造产生一个标签的融合蛋白能够形成一个共价键，多种功能组别，包括荧光，生物素，或珠子。感兴趣的蛋白质必须被克隆，并表示只有一次，然后融合，可以使用各种众多的下游应用，如活细胞内蛋白质的同时标签，蛋白定位和移位脉冲追逐实验，受体的内化研究用荧光底物，有选择性的细胞表面的标签，蛋白质下拉检测，蛋白SDS - PAGE电泳，流式细胞仪，高通量微孔板，生物传感器相互作用实验结合实验检测，以及基于FRET的结合实验。

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">	
		
		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>CHO-K1 Cells</td>
<td>&nbsp;</td>
<td>ATCC</td>
<td>CCL-61</td>
<td>&nbsp;</td>
<tr>
<td>Serum free F-12K</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Lab-Tek II Chambered Coverglass with #1.5 borosilicate coverglass chambers</td>
<td>&nbsp;</td>
<td>Nalgene Nunc Int.</td>
<td>155409</td>
<td>Lot: 100808-8-0</td>
</tr>
<tr>
<td>DMEM</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Hoechst 33342, trihydrochloride, trihydrate (10 mg/ml solution in water, 16.2 mM solution)</td>
<td>&nbsp;</td>
<td>Invitrogen Molecular Probes</td>
<td>H3570</td>
<td>470519</td>
</tr>
<tr>
<td>Zeiss Apotome Axiovert 200M fluorescent microscope</td>
<td>&nbsp;</td>
<td>Zeiss</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Transpass V</td>
<td>&nbsp;</td>
<td>New England Biolabs</td>
<td>M2561S</td>
<td>0030709</td>
</tr>
<tr>
<td>Transpass D2</td>
<td>&nbsp;</td>
<td>New England Biolabs</td>
<td>M2554S</td>
<td>0060802</td>
</tr>
<tr>
<td>SNAP-Cell TMR Star</td>
<td>&nbsp;</td>
<td>New England Biolabs</td>
<td>S9105S</td>
<td>0010811</td>
</tr>
<tr>
<td>pSNAP-ADBR2 Control Plasmid</td>
<td>&nbsp;</td>
<td>New England Biolabs</td>
<td>N9178S</td>
<td>0010811</td>
</tr>
<tr>
<td>pSNAP-H2B Control Plasmid </td>
<td>&nbsp;</td>
<td>New England Biolabs</td>
<td>N9179S</td>
<td>0010811</td>
</tr>		</tbody>
		</table>
		</div>

fluorescent labeling of cos-7 expressing snap-tag fusion proteins for live cell imaging

SNAP标签和剪辑标签蛋白标签制度，包括荧光染料分子，使特定的共价结合，一个活细胞中的兴趣的蛋白质。这些系统提供了一个广阔的选择优化一系列的成像仪器的荧光底物。一旦克隆并表达，标记蛋白可用于许多下游应用的各种基材，而无需再次进行克隆。使用这个系统有两个步骤：利益作为一个SNAP标签的融合，并选择SNAP标签基材的融合标签蛋白的克隆和表达。管理单元的标签是一种小分子蛋白基于人类Ø<sup&gt; 6</sup&gt; alkylguanine的DNA - alkyltransferase（hAGT），DNA修复蛋白。 SNAP - TAG标签染料标记的鸟嘌呤或通过一个苄连接器氯嘧啶离开组。在标记反应，基板取代的苄基共价连接的SNAP标签。夹子标签是SNAP标签的修改后的版本，设计benzylcytosine而不是苄基鸟嘌呤衍生物反应。 SNAP标签一起使用时，夹子标记允许的两种蛋白质的正交性，互补性的标签，同时在相同的细胞。

Watch this Scientific Journal Video about Fluorescent Labeling of COS-7 Expressing SNAP-tag Fusion Proteins for Live Cell Imaging at JoVE.com

Fluorescent Labeling of COS-7 Expressing SNAP-tag Fusion Proteins for Live Cell Imaging

SNAP标签和剪辑标签蛋白标签制度，包括荧光染料分子，使特定的共价结合，一个活细胞中的兴趣的蛋白质。一旦克隆和表达，标记蛋白可用于许多下游应用的各种基材，而无需再次进行克隆。

对活细胞成像的SNAP - Tag融合蛋白的荧光标记的COS - 7

SNAP-tag and CLIP-tag protein labeling systems enable the specific, covalent attachment of molecules, including fluorescent dyes, to a protein of interest ...

fluorescent-labeling-cos-7-expressing-snap-tag-fusion-proteins-for

Research

JoVE Journal

Biology

22.9K 次观看.  New England Biolabs. SNAP标签和剪辑标签蛋白标签制度，包括荧光染料分子，使特定的共价结合，一个活细胞中的兴趣的蛋白质。一旦克隆和表达，标记蛋白可用于许多下游应用的各种基材，而无需再次进行克隆。

视频: Fluorescent Labeling of COS-7 Expressing SNAP-tag Fusion Proteins for Live Cell Imaging

Labeling Stem Cells with Fluorescent Dyes for non-invasive Detection with Optical Imaging

Optical imaging (OI) is an easy, fast and inexpensive tool for in vivo monitoring of new stem cell based therapies. The technique is based on ex vivo labeling of stem cells with a fluorescent dye, subsequent intravenous injection of the labeled cells and visualization of their accumulation in specific target organs or pathologies. The presented technique demonstrates how we label human mesenchymal stem cells (hMSC) by simple incubation with the lipophilic fluorescent dye DiD (C67H103CIN2O3S) and how we label human embryonic stem cells (hESC) with the FDA approved fluorescent dye Indocyanine Green (ICG). The uptake mechanism is via adherence and diffusion of the lypophilic dye across the phospholipid cell membrane bilayer. The labeling efficiency is usually improved if the cells are incubated with the dye in serum-free media as opposed to incubation in serum-containing media. Furthermore, the addition of the transfection agent Protamine Sulfate significantly improves contrast agent uptake.

This video shows techniques for labeling of human embryonic stem cells and mesenchymal stem cells with fluorescent dyes. This technique can be used for an in vivo tracking of transplanted stem cells with optical imaging and for histopathological correlations with fluorescence microscopy.

与非侵入性检测荧光染料标记的干细胞与光学成像

Optical imaging (OI) is an easy, fast and inexpensive tool for in vivo monitoring of new stem cell based therapies. The technique is based on ex vivo ...

科研

生物学

Live Cell Imaging of F-actin Dynamics via Fluorescent Speckle Microscopy (FSM)

In this protocol we describe the use of Fluorescent Speckle Microscopy (FSM) to capture high-resolution images of actin dynamics in PtK1 cells. A unique advantage of FSM is its ability to capture the movement and turnover kinetics (assembly/disassembly) of the F-actin network within living cells. This technique is particularly useful in deriving quantitative measurements of F-actin dynamics when paired with computer vision software (qFSM).  We describe  the selection, microinjection and visualization of fluorescent actin probes in living cells. Importantly, similar procedures are applicable to visualizing other macomolecular assemblies. FSM has been demonstrated for microtubules, intermediate filaments, and adhesion complexes.  

Live Cell Imaging of F-actin Dynamics via Fluorescent Speckle Microscopy FSM

Selection, microinjection, and imaging of fluorescently-labeled F-actin via fluorescent speckle microscopy (FSM).

F - actin的动力学通过荧光活细胞成像斑点显微镜（密克罗尼西亚）

In this protocol we describe the use of Fluorescent Speckle Microscopy (FSM) to capture high-resolution images of actin dynamics in PtK1 cells. A unique ...

Fluorescent Labeling of Drosophila Heart Structures

The Drosophila melanogaster dorsal vessel, or heart, is a tubular structure comprised of a single layer of contractile cardiomyocytes, pericardial cells that align along each side of the heart wall, supportive alary muscles and, in adults, a layer of ventral longitudinal muscle cells. The contractile fibers house conserved constituents of the muscle cytoarchitecture including densely packed bundles of myofibrils and cytoskeletal/submembranous protein complexes, which interact with homologous components of the extracellular matrix. Here we describe a protocol for the fixation and the fluorescent labeling of particular myocardial elements from the hearts of dissected larvae and semi-intact adult Drosophila. Specifically, we demonstrate the labeling of sarcomeric F-actin and of &alpha;-actinin in larval hearts. Additionally, we perform labeling of F-actin and &alpha;-actinin in myosin-GFP expressing adult flies and of &alpha;-actinin and pericardin, a type IV extracellular matrix collagen, in wild type adult hearts. Particular attention is given to a mounting strategy for semi-intact adult hearts that minimizes handling and optimizes the opportunity for maintaining the integrity of the cardiac tubes and the associated tissues. These preparations are suitable for imaging via fluorescent and confocal microscopy. Overall, this procedure allows for careful and detailed analysis of the structural characteristics of the heart from a powerful genetically tractable model system.

Fluorescent Labeling of Drosophila Heart Structures

Here we describe a basic protocol for fluorescent labeling of different elements of heart tubes from larva and adult Drosophila melanogaster. These specimens are well-suited for imaging via fluorescent or confocal microscopy. This technique permits detailed structural analysis of the features of the hearts from a powerful model organism.

荧光标记的果蝇心结构

The Drosophila melanogaster dorsal vessel, or heart, is a tubular structure comprised of a single layer of contractile cardiomyocytes, pericardial cells ...

Transplantation of GFP-expressing Blastomeres for Live Imaging of Retinal and Brain Development in Chimeric Zebrafish Embryos

Cells change extensively in their locations and property during embryogenesis. These changes are regulated by the interactions between the cells and their environment. Chimeric embryos, which are composed of cells of different genetic background, are great tools to study the cell-cell interactions mediated by genes of interest. The embryonic transparency of zebrafish at early developmental stages permits direct visualization of the morphogenesis of tissues and organs at the cellular level. Here, we demonstrate a protocol to generate chimeric retinas and brains in zebrafish embryos and to perform live imaging of the donor cells. The protocol covers the preparation of transplantation needles, the transplantation of GFP-expressing donor blastomeres to GFP-negative hosts, and the examination of donor cell behavior under live confocal microscopy. With slight modifications, this protocol can also be used to study the embryonic development of other tissues and organs in zebrafish. The advantages of using GFP to label donor cells are also discussed. 

We demonstrate a protocol to generate chimeric zebrafish embryos for live imaging cellular behavior during embryogenesis.

移植绿色荧光蛋白表达对视网膜和大脑发育的实时成像嵌合斑马鱼胚胎的卵裂球

Cells change extensively in their locations and property during embryogenesis. These changes are regulated by the interactions between the cells and their ...

Photoconversion of Purified Fluorescent Proteins and Dual-probe Optical Highlighting in Live Cells

Photoconvertible fluorescent proteins (pc-FPs) are a class of fluorescent proteins with "optical highlighter" capability, meaning that the color of fluorescence can be changed by exposure to light of a specific wavelength. Optical highlighting allows noninvasive marking of a subpopulation of fluorescent molecules, and is therefore ideal for tracking single cells or organelles.
Critical parameters for efficient photoconversion are the intensity and the exposure time of the photoconversion light. If the intensity is too low, photoconversion will be slow or not occur at all. On the other hand, too much intensity or too long exposure can photobleach the protein and thereby reduce the efficiency of photoconversion.
This protocol describes a general approach how to set up a confocal laser scanning microscope for pc-FP photoconversion applications. First, we describe a procedure for preparing purified protein droplet samples. This sample format is very convenient for studying the photophysical behavior of fluorescent proteins under the microscope. Second, we will use the protein droplet sample to show how to configure the microscope for photoconversion. And finally, we will show how to perform optical highlighting in live cells, including dual-probe optical highlighting with mOrange2 and Dronpa.

This protocol describes a general approach to perform photoconversion of fluorescent proteins on a confocal laser scanning microscope. We describe procedures for the photoconversion of puried protein samples, as well as for dual-probe optical highlighting in live cells with mOrange2 and Dronpa.

在活细胞荧光蛋白的双探头光学突出纯净的光转化的

Photoconvertible fluorescent proteins (pc-FPs) are a class of fluorescent proteins with "optical highlighter" capability, meaning that the color of ...

Two- and Three-Dimensional Live Cell Imaging of DNA Damage Response Proteins

Double-strand breaks (DSBs) are the most deleterious DNA lesions a cell can encounter. If left unrepaired, DSBs harbor great potential to generate mutations and chromosomal aberrations1. To prevent this trauma from catalyzing genomic instability, it is crucial for cells to detect DSBs, activate the DNA damage response (DDR), and repair the DNA. When stimulated, the DDR works to preserve genomic integrity by triggering cell cycle arrest to allow for repair to take place or force the cell to undergo apoptosis. The predominant mechanisms of DSB repair occur through nonhomologous end-joining (NHEJ) and homologous recombination repair (HRR) (reviewed in2). There are many proteins whose activities must be precisely orchestrated for the DDR to function properly. Herein, we describe a method for 2- and 3-dimensional (D) visualization of one of these proteins, 53BP1.
The p53-binding protein 1 (53BP1) localizes to areas of DSBs by binding to modified histones3,4, forming foci within 5-15 minutes5. The histone modifications and recruitment of 53BP1 and other DDR proteins to DSB sites are believed to facilitate the structural rearrangement of chromatin around areas of damage and contribute to DNA repair6. Beyond direct participation in repair, additional roles have been described for 53BP1 in the DDR, such as regulating an intra-S checkpoint, a G2/M checkpoint, and activating downstream DDR proteins7-9. Recently, it was discovered that 53BP1 does not form foci in response to DNA damage induced during mitosis, instead waiting for cells to enter G1 before localizing to the vicinity of DSBs6. DDR proteins such as 53BP1 have been found to associate with mitotic structures (such as kinetochores) during the progression through mitosis10.
In this protocol we describe the use of 2- and 3-D live cell imaging to visualize the formation of 53BP1 foci in response to the DNA damaging agent camptothecin (CPT), as well as 53BP1's behavior during mitosis. Camptothecin is a topoisomerase I inhibitor that primarily causes DSBs during DNA replication. To accomplish this, we used a previously described 53BP1-mCherry fluorescent fusion protein construct consisting of a 53BP1 protein domain able to bind DSBs11. In addition, we used a histone H2B-GFP fluorescent fusion protein construct able to monitor chromatin dynamics throughout the cell cycle but in particular during mitosis12. Live cell imaging in multiple dimensions is an excellent tool to deepen our understanding of the function of DDR proteins in eukaryotic cells.

This protocol describes a method for visualizing a DNA double-strand break signaling protein activated in response to DNA damage as well as its localization during mitosis.

二维和三维活细胞成像的DNA损伤反应蛋白

Double-strand breaks (DSBs) are the most deleterious DNA lesions a cell can encounter. If left unrepaired, DSBs harbor great potential to generate ...

Live Imaging of GFP-labeled Proteins in Drosophila Oocytes

The Drosophila oocyte has been established as a versatile system for investigating fundamental questions such as cytoskeletal function, cell organization, and organelle structure and function. The availability of various GFP-tagged proteins means that many cellular processes can be monitored in living cells over the course of minutes or hours, and using this technique, processes such as RNP transport, epithelial morphogenesis, and tissue remodeling have been described in great detail in Drosophila oocytes1,2.
The ability to perform video imaging combined with a rich repertoire of mutants allows an enormous variety of genes and processes to be examined in incredible detail. One such example is the process of ooplasmic streaming, which initiates at mid-oogenesis3,4. This vigorous movement of cytoplasmic vesicles is microtubule and kinesin-dependent5 and provides a useful system for investigating cytoskeleton function at these stages.
Here I present a protocol for time lapse imaging of living oocytes using virtually any confocal microscopy setup.

Live Imaging of GFP-labeled Proteins in Drosophila Oocytes

A protocol for live imaging of GFP-tagged proteins or autofluorescent structures in individual Drosophila oocytes is described.

GFP标记的蛋白质在实时成像<em&gt;果蝇</em&gt;卵母细胞

The  Drosophila oocyte has been established as a versatile system for investigating  fundamental questions such as cytoskeletal function, cell ...

Live Imaging of Apoptotic Cell Clearance during Drosophila Embryogenesis

The proper elimination of unwanted or aberrant cells through apoptosis and subsequent phagocytosis (apoptotic cell clearance) is crucial for normal development in all metazoan organisms. Apoptotic cell clearance is a highly dynamic process intimately associated with cell death; unengulfed apoptotic cells are barely seen in vivo under normal conditions. In order to understand the different steps of apoptotic cell clearance and to compare 'professional' phagocytes - macrophages and dendritic cells to 'non-professional' - tissue-resident neighboring cells, in vivo live imaging of the process is extremely valuable. Here we describe a protocol for studying apoptotic cell clearance in live Drosophila embryos. To follow the dynamics of different steps in phagocytosis we use specific markers for apoptotic cells and phagocytes. In addition, we can monitor two phagocyte systems in parallel: 'professional' macrophages and 'semi-professional' glia in the developing central nervous system (CNS). The method described here employs the Drosophila embryo as an excellent model for real time studies of apoptotic cell clearance.

Live Imaging of Apoptotic Cell Clearance during Drosophila Embryogenesis

Here we describe an effective method for studying dynamics of apoptotic cell clearance in vivo. This method employs live Drosophila embryos as a powerful model for monitoring phagocytosis of apoptotic cells using specific labeling of apoptotic cells and phagocytes.

凋亡细胞清除过程中实时成像<em&gt;果蝇</em&gt;胚胎发育

The  proper elimination of unwanted or aberrant cells through apoptosis and  subsequent phagocytosis (apoptotic cell clearance) is crucial for normal  ...

Intravital Microscopy for Imaging Subcellular Structures in Live Mice Expressing Fluorescent Proteins

Here we describe a procedure to image subcellular structures in live rodents that is based on the use of confocal intravital microscopy. As a model organ, we use the salivary glands of live mice since they provide several advantages. First, they can be easily exposed to enable access to the optics, and stabilized to facilitate the reduction of the motion artifacts due to heartbeat and respiration. This significantly facilitates imaging and tracking small subcellular structures. Second, most of the cell populations of the salivary glands are accessible from the surface of the organ. This permits the use of confocal microscopy that has a higher spatial resolution than other techniques that have been used for in vivo imaging, such as two-photon microscopy. Finally, salivary glands can be easily manipulated pharmacologically and genetically, thus providing a robust system to investigate biological processes at a molecular level.
In this study we focus on a protocol designed to follow the kinetics of the exocytosis of secretory granules in acinar cells and the dynamics of the apical plasma membrane where the secretory granules fuse upon stimulation of the beta-adrenergic receptors. Specifically, we used a transgenic mouse that co-expresses cytosolic GFP and a membrane-targeted peptide fused with the fluorescent protein tandem-Tomato. However, the procedures that we used to stabilize and image the salivary glands can be extended to other mouse models and coupled to other approaches to label in vivo cellular components, enabling the visualization of various subcellular structures, such as endosomes, lysosomes, mitochondria, and the actin cytoskeleton.

Intravital microscopy is a powerful tool that enables imaging various biological processes in live animals. In this article, we present a detailed method for imaging the dynamics of subcellular structures, such as the secretory granules, in the salivary glands of live mice.

活体显微镜成像的亚细胞结构的活体小鼠表达荧光蛋白

Here we describe a procedure to image subcellular structures in live rodents that is based on the use of confocal intravital microscopy. As a model organ, ...

Expression of Fluorescent Fusion Proteins in Murine Bone Marrow-derived Dendritic Cells and Macrophages

Dendritic cells and macrophages are crucial cells that form the first line of defense against pathogens. They also play important roles in the initiation of an adaptive immune response. Experimental work with these cells is rather challenging. Their abundance in organs and tissues is relatively low. As a result, they cannot be isolated in large numbers. They are also difficult to transfect with cDNA constructs. In the murine model, these problems can be partially overcome by in vitro differentiation from bone marrow progenitors in the presence of M-CSF for macrophages or GM-CSF for dendritic cells. In this way, it is possible to obtain large amounts of these cells from very few animals. Moreover, bone marrow progenitors can be transduced with retroviral vectors carrying cDNA constructs during early stages of cultivation prior to their differentiation into bone marrow derived dendritic cells and macrophages. Thus, retroviral transduction followed by differentiation in vitro can be used to express various cDNA constructs in these cells. The ability to express ectopic proteins substantially extends the range of experiments that can be performed on these cells, including live cell imaging of fluorescent proteins, tandem purifications for interactome analyses, structure-function analyses, monitoring of cellular functions with biosensors and many others. In this article, we describe a detailed protocol for retroviral transduction of murine bone marrow derived dendritic cells and macrophages with vectors coding for fluorescently-tagged proteins. On the example of two adaptor proteins, OPAL1 and PSTPIP2, we demonstrate its practical application in flow cytometry and microscopy. We also discuss the advantages and limitations of this approach.

In this article, we provide a detailed protocol for the expression of fluorescent fusion proteins in murine bone marrow derived dendritic cells and macrophages. The method is based on the transduction of bone marrow progenitors with retroviral constructs followed by differentiation into macrophages and dendritic cells in vitro.

荧光融合蛋白在小鼠骨髓基质树突状细胞和巨噬细胞中的表达

Dendritic cells and macrophages are crucial cells that form the first line of defense against pathogens. They also play important roles in the initiation ...