This work was supported by the Singapore Academic research council (ARC) [grant number 90/07]. We thank Radiodurans for the support.

The complete and detailed text protocol for this experimental procedure is available in Current Protocols in Molecular Biology. Detailed step-by-step instructions for the assembly of the gel sandwich and for gel apparatus can be found on the BioRad website 3.
Required equipment: 
 Glass plates (inner and outer) 
 10 cm cell: 10.1 x 7.3 cm (inner plate), 10.1 x 8.2 cm (outer plate), BioRad 
 20 cm cell: 20 x 20 cm (inner plate), 20 x 22.3 cm (outer plate), BioRad 
 0.5-1.5 mm gel comb and spacers 
 Gel casting stand 
 Gel apparatus with lid and cables 
 High voltage power supply 
 Heating block or water bath 
 Serological pipettes and Pipette aid 
 Pipette and Pipette tips 
 Gel dryer or scanner
Reagents and Solutions: 
 Urea (ultrapure) 
 40% polyacrylamide solution (29:1) 
 10 x TBE solution (Tris-Borate, EDTA buffer) 
 Deionized, distilled water 
 TEMED 
 30% (w/v) ammonium persulfate solution 
 0.5 x TBE solution 
 Formamide 
 EDTA 
 Xylene cyanol 
 Bromphenol blue 
 Methanol 
 Ethanol
<table border="1" cellspacing="0" cellpadding="0">
<tbody>
 <tr>
 <td>Volume</td>
 <td colspan="3" style="text-align:center;">50 ml</td>
 <td colspan="3" style="text-align:center;">60 ml</td>
 <td colspan="3" style="text-align:center;">10 ml</td>
 </tr>
 <tr>
 <td>Acrylamide concentration</td>
 <td>10%</td>
 <td>12.5%</td>
 <td>15%</td>
 <td>10%</td>
 <td>12.5%</td>
 <td>15%</td>
 <td>10%</td>
 <td>12.5%</td>
 <td>15%</td>
 </tr>
 <tr>
 <td>g UREA</td>
 <td>24</td>
 <td>24</td>
 <td>24</td>
 <td>28.8</td>
 <td>28.8</td>
 <td>28.8</td>
 <td>4.8</td>
 <td>4.8</td>
 <td>4.8</td>
 </tr>
 <tr>
 <td>ml 40% Acryl (29:1)</td>
 <td>12.5</td>
 <td>15.625</td>
 <td>18.75</td>
 <td>15</td>
 <td>18.75</td>
 <td>22.5</td>
 <td>2.5</td>
 <td>3.125</td>
 <td>3.75</td>
 </tr>
 <tr>
 <td>ul 30% APS</td>
 <td>166</td>
 <td>166</td>
 <td>166</td>
 <td>199.2</td>
 <td>199.2</td>
 <td>199.2</td>
 <td>33</td>
 <td>33</td>
 <td>33</td>
 </tr>
 <tr>
 <td>ul TEMED</td>
 <td>20</td>
 <td>20</td>
 <td>20</td>
 <td>24</td>
 <td>24</td>
 <td>24</td>
 <td>4</td>
 <td>4</td>
 <td>4</td>
 </tr>
 <tr>
 <td>10 x TBE</td>
 <td>5</td>
 <td>5</td>
 <td>5</td>
 <td>6</td>
 <td>6</td>
 <td>6</td>
 <td>1</td>
 <td>1</td>
 <td>1</td>
 </tr>
 <tr>
 <td colspan="10">Fill up the volume with deionized, distilled water</td>
 </tr>
 </tbody>
</table>
Table 1: Reagents and solutions needed for various acrylamide concentrations and volumes for resolving single stranded oligonucleotides
Gel sandwich assembly and gel preparation
<ol>
<li>Assemble the gel according to manufacturers description and fix the gel in the gel-casting chamber 3. Use 0.5-1.5 mm thick spacers.</li>
<li>Prepare the appropriate polyacrylamide solution according to current protocols in molecular biology or as listed in Table 1. For a denaturing acrylamide gel of 20 cm x 22 cm x 1.5 mm, 60 ml of gel solution and for a 10.1 x 8.2 cm x 1 mm gel 5 ml gel solution is sufficient. Larger gels are used when the expected products/bands are within the range of a few bases, then a longer gel will resolve bands with a difference of a single nucleotide. If the expected bands differ in more than 10 nucleotides, smaller gels will be suitable to resolve the fragments. Choose the percentage of polyacrylamide that suits your separation requirements, a higher polyacrylamide concentrations will resolve lower molecular weight fragments. Use ultrapure urea and mix with the desired amount of acrylamide. Add TBE buffer to the gel mix to get a final concentration of 0.5-1 x TBE and fill up the volume with deionized, distilled water. Heat the solution for 20 seconds in the microwave and mix it gently. For larger gel volumes repeat this step until the solution is hand warm.</li>
<li>Pour the gel immediately using a serological pipette and an automatic pipette aid between the two glass plates. Avoid introducing air bubbles. Insert the comb and let the gel polymerize for 30-60 minutes.</li>
</ol>
Set up the electrophoresis apparatus and prerun the gel
<ol>
<li>Dismount the gel from the casting chamber and assembly it to the gel apparatus according to manufactures instructions 3.</li>
<li>Fill the lower buffer chamber wit running buffer (0.5-1 x TBE) that the glass plates will be submerged 2-3 cm with buffer. Fill the upper buffer chamber up to the top of the gel with running buffer.</li>
<li>Carefully remove the comb and rinse the wells with running buffer by using a pipette and gel loading tips.</li>
<li>Attach the lid of the gel system and plug in the cables to a high voltage power supply. Before you can load your samples you have to prerun the gel for at least 30 minutes to heat the gel up and to remove remaining urea from the gel. The optimal temperature should be between 45-55 &deg;C. Avoid temperatures higher than 60 &deg;C as bands could smear or the glass plates could crack. Choose constant watts for the prerun (15-25 W per gel).</li>
</ol>
Sample preparation
<ol>
<li>In the meantime prepare your samples. Therefore, add the appropriate amount of 2 x gel loading mix to your sample. The loading mix usually contains 90% formamide, 0.5% EDTA, 0.1% xylene cyanol and 0.1% bromphenol blue.</li>
<li>Before the samples can be loaded on the gel, samples must be heat denatured by heating the samples between 70-90 &deg;C for a few minutes.</li>
</ol>
Load and run the gel
<ol>
<li>When the prerun is finished, remove the lid and rinse the pockets thoroughly as described before as urea has leached into the wells.</li>
<li>Apply the samples carefully from the bottom of the pocket. Avoid introducing air bubbles. Loading buffer has to be applied to empty pockets to maintain equal conditions during the run.</li>
<li>Assemble the lid and run the gel at constant watts to maintain a gel temperature of 55 &deg;C similar to the prerun. Observe the migration of the marker dyes until the dye front reached the lower end of the gel. The run duration is dependent on the percentage of used acrylamide, ionic strength of the buffer and gel thickness. A run can last between 2-4 hours. 
 Check on the temperature of the gel. A gel thermometer can help to monitor the right temperature during the run.</li>
 </ol>
Process the gel
<ol>
<li>When the dye front has reached the end of the gel put the gel out of the lower buffer chamber. Remove the gel from the chamber and loosen the clamps. Pull away the spacers and carefully dissemble the glass plates. If necessary cut away the upper well containing gel part.</li>
<li>Carefully transfer the gel into a dish with gel fixation solution (same concentration of TBE plus 5-10% Methanol and Ethanol). Leave the gel into the solution for 5-10 minutes and change the buffer twice.</li>
<li>The gel is ready for further processing using a vacuum gel dryer or direct scanning of the gel.</li>
</ol>

<ol>
	<li>Maniatis, T., Jeffrey, A., van deSande, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chain+length+determination+of+small+double-+and+single-stranded+DNA+molecules+by+polyacrylamide+gel+electrophoresis.">Chain length determination of small double- and single-stranded DNA molecules by polyacrylamide gel electrophoresis.</a> Biochemistry. 14, 3787-3794 (1975).</li><li>Albright, L. M., Slatko, B. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Denaturing+polyacrylamide+gel+electrophoresis.">Denaturing polyacrylamide gel electrophoresis.</a> Curr Protoc Nucleic Acid Chem. , (2001).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> PROTEAN II xi Cell and PROTEAN II xi 2-D Cell Instruction Manual. , (2001).</li></ol>

The authors have nothing to disclose.

<ol>
<li>The band sharpness depends on several factors. The volume of sample loaded for sharp bands should be as small as possible, i.e. ideally between 1-5 &mu;l. However, up to 15 &mu;l can be loaded which still ensures acceptable resolution. Less sample volume results in sharper bands.</li>
<li>The band quality is also dependent on the gel thickness. Thinner gels, such as 0.75 mm show better results than 1.5 mm thick gels.</li>
<li>The shape of bands can also be influenced during gel loading, if the sample is not applied equally into the gel...

denaturing urea polyacrylamide gel electrophoresis (urea page)

Urea PAGE or denaturing urea polyacrylamide gel electrophoresis employs 6-8 M urea, which denatures secondary DNA or RNA structures and is used for their separation in a polyacrylamide gel matrix based on the molecular weight. Fragments between 2 to 500 bases, with length differences as small as a single nucleotide, can be separated using this method1. The migration of the sample is dependent on the chosen acrylamide concentration. A higher percentage of polyacrylamide resolves lower molecular weight fragments. The combination of urea and temperatures of 45-55 &deg;C during the gel run allows for the separation of unstructured DNA or RNA molecules.
In general this method is required to analyze or purify single stranded DNA or RNA fragments, such as synthesized or labeled oligonucleotides or products from enzymatic cleavage reactions.
In this video article we show how to prepare and run the denaturing urea polyacrylamide gels. Technical tips are included, in addition to the original protocol 1,2.

Watch this Scientific Journal Video about Denaturing Urea Polyacrylamide Gel Electrophoresis Urea PAGE at JoVE.com

Denaturing Urea Polyacrylamide Gel Electrophoresis Urea PAGE

Denaturing urea polyacrylamide gel electrophoresis is used to separate single-stranded DNA or RNA up to a limit of 500 nucleotides. Urea in combination with heat denatures samples and unstructured single strands migrate within the gel matrix according to their molecular weight.

Denaturing Urea Polyacrylamide Gel Electrophoresis (Urea PAGE)

Urea PAGE or denaturing urea polyacrylamide gel electrophoresis employs 6-8 M urea, which denatures secondary DNA or RNA structures and is used for their ...

denaturing-urea-polyacrylamide-gel-electrophoresis-urea-page

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78.2K Views.  Nanyang Technological University, Singapore - NTU. Denaturing urea polyacrylamide gel electrophoresis is used to separate single-stranded DNA or RNA up to a limit of 500 nucleotides. Urea in combination with heat denatures samples and unstructured single strands migrate within the gel matrix according to their molecular weight.

Video: Denaturing Urea Polyacrylamide Gel Electrophoresis Urea PAGE

Denaturing Gradient Gel Electrophoresis (DGGE)

Denaturing Gradient Gel Electrophoresis DGGE

Screening for Amyloid Aggregation by Semi-Denaturing Detergent-Agarose Gel Electrophoresis

Amyloid aggregation is associated with numerous protein misfolding pathologies and underlies the infectious properties of prions, which are conformationally self-templating proteins that are thought to have beneficial roles in lower organisms.  Amyloids have been notoriously difficult to study due to their insolubility and structural heterogeneity.  However, resolution of amyloid polymers based on size and detergent insolubility has been made possible by Semi-Denaturing Detergent-Agarose Gel Electrophoresis (SDD-AGE).  This technique is finding widespread use for the detection and characterization of amyloid conformational variants.  Here, we demonstrate an adaptation of this technique that facilitates its use in large-scale applications, such as screens for novel prions and other amyloidogenic proteins.  The new SDD-AGE method uses capillary transfer for greater reliability and ease of use, and allows any sized gel to be accomodated.  Thus, a large number of samples, prepared from cells or purified proteins, can be processed simultaneously for the presence of SDS-insoluble conformers of tagged proteins.

SDD-AGE is a useful technique for the detection and characterization of amyloid-like polymers in cells. Here we demonstrate an adaptation that makes this technique amenable to large-scale applications.

Amyloid aggregation is associated with numerous protein misfolding pathologies and underlies the infectious properties of prions, which are ...

Fast and Sensitive Colloidal Coomassie G-250 Staining for Proteins in Polyacrylamide Gels

Coomassie Brilliant Blue (CBB) is a dye commonly used for the visualization of proteins separated by SDS-PAGE, offering a simple staining procedure and high quantitation. Furthermore, it is completely compatible with mass spectrometric protein identification. But despite these advantages, CBB is regarded to be less sensitive than silver or fluorescence stainings and therefore rarely used for the detection of proteins in analytical gel-based proteomic approaches.
Several improvements of the original Coomassie protocol1 have been made to increase the sensitivity of CBB. Two major modifications were introduced to enhance the detection of low-abundant proteins by converting the dye molecules into colloidal particles: In 1988, Neuhoff and colleagues applied 20% methanol and higher concentrations of ammonium sulfate into the CBB G-250 based staining solution2, and in 2004 Candiano et al. established Blue Silver using CBB G-250 with phosphoric acid in the presence of ammonium sulfate and methanol3. Nevertheless, all these modifications just allow a detection of approximately 10 ng protein. A widely fameless protocol for colloidal Coomassie staining was published by Kang et al. in 2002 where they modified Neuhoff's colloidal CBB staining protocol regarding the complexing substances. Instead of ammonium sulfate they used aluminum sulfate and methanol was replaced by the less toxic ethanol4. The novel aluminum-based staining in Kang's study showed superior sensitivity that detects as low as 1 ng/band (phosphorylase b) with little sensitivity variation depending on proteins.
Here, we demonstrate application of Kang's protocol for fast and sensitive colloidal Coomassie staining of proteins in analytical purposes. We will illustrate the quick and easy protocol using two-dimensional gels routinely performed in our working group.

This video shall popularize a colloidal Coomassie G-250 staining protocol according to Kang et al. for the detection of average 4 ng protein in gels. The staining is completed within 2 hours and without any effort. We routinely use Kang's protocol for analytical purposes in gel-based proteomics.

Coomassie Brilliant Blue (CBB) is a dye commonly used for the visualization of proteins separated by SDS-PAGE, offering a simple staining procedure and ...

Blue Native Polyacrylamide Gel Electrophoresis (BN-PAGE) for Analysis of Multiprotein Complexes from Cellular Lysates

Multiprotein complexes (MPCs) play a crucial role in cell signalling, since most proteins can be found in functional or regulatory complexes with other proteins (Sali, Glaeser et al. 2003). Thus, the study of protein-protein interaction networks requires the detailed characterization of MPCs to gain an integrative understanding of protein function and regulation. For identification and analysis, MPCs must be separated under native conditions. In this video, we describe the analysis of MPCs by blue native polyacrylamide gel electrophoresis (BN-PAGE). BN-PAGE is a technique that allows separation of MPCs in a native conformation with a higher resolution than offered by gel filtration or sucrose density ultracentrifugation, and is therefore useful to determine MPC size, composition, and relative abundance (Sch&auml;gger and von Jagow 1991); (Sch&auml;gger, Cramer et al. 1994). By this method, proteins are separated according to their hydrodynamic size and shape in a polyacrylamide matrix. Here, we demonstrate the analysis of MPCs of total cellular lysates, pointing out that lysate dialysis is the crucial step to make BN-PAGE applicable to these biological samples. Using a combination of first dimension BN- and second dimension SDS-PAGE, we show that MPCs separated by BN-PAGE can be further subdivided into their individual constituents by SDS-PAGE. Visualization of the MPC components upon gel separation is performed by standard immunoblotting. As an example for MPC analysis by BN-PAGE, we chose the well-characterized eukaryotic 19S, 20S, and 26S proteasomes.

Blue Native Polyacrylamide Gel Electrophoresis BN-PAGE for Analysis of Multiprotein Complexes from Cellular Lysates

In this video, we describe the characterization of multiprotein complexes (MPCs) by blue native polyacrylamide gel electrophoresis (BN-PAGE). In a first dimension, dialyzed cellular lysates are separated by BN-PAGE to identify individual MPCs. In a second dimension SDS-PAGE, MPCs of interest are further subdivided to analyze their constituents by immunoblotting.

Multiprotein complexes (MPCs) play a crucial role in cell signalling, since most proteins can be found in functional or regulatory complexes with other ...

Agarose Gel Electrophoresis for the Separation of DNA Fragments

Agarose gel electrophoresis is the most effective way of separating DNA fragments of varying sizes ranging from 100 bp to 25 kb1. Agarose is isolated from the seaweed genera Gelidium and Gracilaria, and consists of repeated agarobiose (L- and D-galactose) subunits2. During gelation, agarose polymers associate non-covalently and form a network of bundles whose pore sizes determine a gel&#39;s molecular sieving properties. The use of agarose gel electrophoresis revolutionized the separation of DNA. Prior to the adoption of agarose gels, DNA was primarily separated using sucrose density gradient centrifugation, which only provided an approximation of size. To separate DNA using agarose gel electrophoresis, the DNA is loaded into pre-cast wells in the gel and a current applied. The phosphate backbone of the DNA (and RNA) molecule is negatively charged, therefore when placed in an electric field, DNA fragments will migrate to the positively charged anode. Because DNA has a uniform mass/charge ratio, DNA molecules are separated by size within an agarose gel in a pattern such that the distance traveled is inversely proportional to the log of its molecular weight3. The leading model for DNA movement through an agarose gel is &#34;biased reptation&#34;, whereby the leading edge moves forward and pulls the rest of the molecule along4. The rate of migration of a DNA molecule through a gel is determined by the following: 1) size of DNA molecule; 2) agarose concentration; 3) DNA conformation5; 4) voltage applied, 5) presence of ethidium bromide, 6) type of agarose and 7) electrophoresis buffer. After separation, the DNA molecules can be visualized under uv light after staining with an appropriate dye. By following this protocol, students should be able to: 
 
1. Understand the mechanism by which DNA fragments are separated within a gel matrix 
2. Understand how conformation of the DNA molecule will determine its mobility through a gel matrix 
3. Identify an agarose solution of appropriate concentration for their needs 
4. Prepare an agarose gel for electrophoresis of DNA samples 
5. Set up the gel electrophoresis apparatus and power supply 
6. Select an appropriate voltage for the separation of DNA fragments 
7. Understand the mechanism by which ethidium bromide allows for the visualization of DNA bands 
8. Determine the sizes of separated DNA fragments 
&#160;

A basic protocol for the separation of DNA fragments using agarose gel electrophoresis is described.

Agarose gel electrophoresis is the most effective way of separating DNA fragments of varying sizes ranging from 100 bp to 25 kb1. Agarose is isolated from ...

Preparation of DNA-crosslinked Polyacrylamide Hydrogels

Mechanobiology is an emerging scientific area that addresses the critical role of physical cues in directing cell morphology and function. For example, the effect of tissue elasticity on cell function is a major area of mechanobiology research because tissue stiffness modulates with disease, development, and injury. Static tissue-mimicking materials, or materials that cannot alter stiffness once cells are plated, are predominately used to investigate the effects of tissue stiffness on cell functions. While information gathered from static studies is valuable, these studies are not indicative of the dynamic nature of the cellular microenvironment in vivo. To better address the effects of dynamic stiffness on cell function, we developed a DNA-crosslinked polyacrylamide hydrogel system (DNA gels). Unlike other dynamic substrates, DNA gels have the ability to decrease or increase in stiffness after fabrication without stimuli. DNA gels consist of DNA crosslinks that are polymerized into a polyacrylamide backbone. Adding and removing crosslinks via delivery of single-stranded DNA allows temporal, spatial, and reversible control of gel elasticity. We have shown in previous reports that dynamic modulation of DNA gel elasticity influences fibroblast and neuron behavior. In this report and video, we provide a schematic that describes the DNA gel crosslinking mechanisms and step-by-step instructions on the preparation DNA gels.

Our laboratory has developed DNA-crosslinked polyacrylamide hydrogels, a dynamic hydrogel system, to better understand the effects of modulating tissue stiffness on cell function. Here, we provide schematics, descriptions, and protocols to prepare these hydrogels.

Mechanobiology is an emerging scientific area that addresses the critical role of physical cues in directing cell morphology and function. For example, ...

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Mucins are high-molecular-weight glycoconjugates, with size ranging from 0.2 to 200 megadalton (MDa). As a result of their size, mucins do not penetrate conventional polyacrylamide gels and require larger pores for separation. We provide a detailed protocol for mucin agarose gel electrophoresis to assess relative quantification and study polymer assembly.


Mucins, the heavily-glycosylated proteins lining mucosal surfaces, have evolved as a key component of innate defense by protecting the epithelium against ...

Analysis of Mitochondrial Respiratory Chain Complexes in Cultured Human Cells using Blue Native Polyacrylamide Gel Electrophoresis and Immunoblotting

Mitochondrial respiration is performed by oxidative phosphorylation (OXPHOS) complexes within mitochondria. Internal and environmental factors can perturb the assembly and stability of OXPHOS complexes. This protocol describes the analysis of mitochondrial respiratory chain complexes by blue native polyacrylamide gel electrophoresis (BN-PAGE) in application to cultured human cells. First, mitochondria are extracted from the cells using digitonin, then using lauryl maltoside, the intact OXPHOS complexes are isolated from the mitochondrial membranes. The OXPHOS complexes are then resolved by gradient gel electrophoresis in the presence of the negatively charged dye, Coomassie blue, which prevents protein aggregation and ensures electrophoretic mobility of protein complexes towards the cathode. Finally, the OXPHOS complexes are detected by standard immunoblotting. Thus, BN-PAGE is a convenient and inexpensive technique that can be used to evaluate the assembly of entire OXPHOS complexes, in contrast to the basic SDS-PAGE allowing the study of only individual OXPHOS complex subunits.

This protocol demonstrates the analysis of mitochondrial respiratory chain complexes by blue native polyacrylamide gel electrophoresis. Here the method applied to cultured human cells is described.

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Detection of Glycosaminoglycans by Polyacrylamide Gel Electrophoresis and Silver Staining

Sulfated glycosaminoglycans (GAGs) such as heparan sulfate (HS) and chondroitin sulfate (CS) are ubiquitous in living organisms and play a critical role in a variety of basic biological structures and processes. As polymers, GAGs exist as a polydisperse mixture containing polysaccharide chains that can range from 4000 Da to well over 40,000 Da. Within these chains exists domains of sulfation, conferring a pattern of negative charge that facilitates interaction with positively charged residues of cognate protein ligands. Sulfated domains of GAGs must be of sufficient length to allow for these electrostatic interactions. To understand the function of GAGs in biological tissues, the investigator must be able to isolate, purify, and measure the size of GAGs. This report describes a practical and versatile polyacrylamide gel electrophoresis-based technique that can be leveraged to resolve relatively small differences in size between GAGs isolated from a variety of biological tissue types.

This report describes techniques to isolate and purify sulfated glycosaminoglycans (GAGs) from biological samples and a polyacrylamide gel electrophoresis approach to approximate their size. GAGs contribute to tissue structure and influence signaling processes via electrostatic interaction with proteins. GAG polymer length contributes to their binding affinity for cognate ligands.

Sulfated glycosaminoglycans (GAGs) such as heparan sulfate (HS) and chondroitin sulfate (CS) are ubiquitous in living organisms and play a critical role ...

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The pupae of Drosophila melanogaster are immobile for several days during metamorphosis, during which they develop a new body with a thin transparent adult integument. Their immobility and transparency make them ideal for in vivo live imaging experiments. Many studies have focused on the dorsal epithelial monolayer of the pupal&#160;notum because of its accessibility and relatively large size. In addition to the studies of epithelial mechanics and development, the notum has been an ideal tissue to study wound healing. After an injury, the entire epithelial repair process can be captured by live imaging over 6-12 h. Despite the popularity of the notum for live imaging, very few published studies have utilized fixed notum samples. Fixation and staining are common approaches for nearly all other Drosophila tissues, taking advantage of the large repertoire of simple cellular stains and antibodies. However, the pupal notum is fragile and prone to curling and distortion after removal from the body, making it challenging to complement live imaging. This protocol offers a straightforward method for fixing and staining the pupal notum, both intact and after laser-wounding. With this technique, the ventral side of the pupa is glued down to a coverslip to immobilize the pupa, and the notum is carefully removed, fixed, and stained. The notum epithelium is mounted on a slide or between two coverslips to facilitate imaging from the tissue&#39;s dorsal or ventral side.

Dissecting, Fixing, and Visualizing the Drosophila Pupal Notum

The present protocol details the preparation and visualization of fixed tissue of the Drosophila pupal notum. It can be used for either intact or wounded tissue, and the original architecture of the tissue is preserved. The procedures for dissecting, fixing, and staining are all described in this article.

The pupae of Drosophila melanogaster are immobile for several days during metamorphosis, during which they develop a new body with a thin transparent ...