I. Thaw the Cells
Take the frozen vial of TN5 cells, and thaw it in a 37&deg;C water bath. Add 5ml of insect Express medium (Invitrogen, catalog number-10486) in 25cm2 T.C flask. Note that Express five comes without Glutamine; need to add 10ml of 100X glutamine pen strep or Glutamine alone to 1 lt media. Add TN5 cells into it and incubate for 30 minutes in a 27&deg;C incubator. Then, aspirate the medium with DMSO gently without disturbing the cells attached to the bottom of flask. Add ...

<ol>
	<li>Benlagha, K., Weiss, A., Beavis, A., Teyton, L., Bendelac, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+identification+of+glycolipipd+antigen-specific+T+cells+using+fluorecent+CD1d+tetramers.">In vivo identification of glycolipipd antigen-specific T cells using fluorecent CD1d tetramers.</a> J. Exp. Med. 191, 1895-1903 (2000).</li><li>Kinjo, Y., Wu, D., Kim, G., Xing, G. W., Poles, M. A., Ho, D. D., Tsuji, M., Kawahara, K., Wong, C. H., Kronenberg, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recognition+of+bacterial+glycosphingolipids+by+natural+killer+T+cells.">Recognition of bacterial glycosphingolipids by natural killer T cells.</a> Nature. 434, 520-525 (2005).</li><li>Naidenko, O. V., Maher, J. K., Ernst, W. A., Sakai, T., Modlin, R. L., Kronenberg, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Binding+and+antigen+presentation+of+ceramide-containing+glycolipids+by+soluble+mouse+and+human+CD1d+molecules.">Binding and antigen presentation of ceramide-containing glycolipids by soluble mouse and human CD1d molecules.</a> J. Exp. Med. 190, 1069-1080 (1999).</li><li>Porcelli, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+CD1+family:+A+third+lineage+of+antigen-+presenting+molecules.">The CD1 family: A third lineage of antigen- presenting molecules.</a> Adv. Immunol. 59, 1-98 (1995).</li><li>Sidobre, S., Kronemberg, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CD1+tetramers:+A+powerful+tool+for+the+analysis+of+glycolipid-reactive+T+cells.">CD1 tetramers: A powerful tool for the analysis of glycolipid-reactive T cells.</a> J. Immunol. 169, 1340-1348 (2002).</li></ol>

In this procedure, it is shown how to initiate, grow, infect Insect cells and how to titer the baculovirus using these cells. The most important aspects of this procedure are maintenance of cells and to know the exact titer of baculovirus. Once you have generated CD1 tetramers, they can be used as a powerful tool for analysis of glycolipid reactive T cells. Baculovirus systems are also used widely to produce recombinant proteins, including MHC class II tetramers so this procedure has a much wider applicability.

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<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>Express Five SFM</td>
<td> Serum Free Medium</td>
<td>Invitrogen</td>
<td>10486025</td>
<td>&nbsp;</td>
<tr>
<td>High Five TM</td>
<td> Insect Cells</td>
<td>Invitrogen</td>
<td>B855-02</td>
<td>&nbsp;</td>
<tr>
<td>Glutamine Pen strep</td>
<td>Antibiotics</td>
<td>Invitrogen</td>
<td>10378-016</td>
<td>&nbsp;</td>
<tr>
<td>25cm2 TC Flask</td>
<td> Plastic</td>
<td>Fisher</td>
<td>10-126-28</td>
<td>&nbsp;</td>
<tr>
<td>175 cm2 TC Flask</td>
<td> Plug seal flask</td>
<td>Fisher</td>
<td>10-126-8</td>
<td>&nbsp;</td>
<tr>
<td>Erlenmeyer Flask</td>
<td> Cell Culture Flask</td>
<td>Fisher</td>
<td>07 200 672</td>
<td>&nbsp;</td>
<tr>
<td>YM 30 Concenterator</td>
<td>30,000 MWCO</td>
<td>Millipore</td>
<td>UFC 903096</td>
<td>&nbsp;</td>
<tr>
<td>FPLC equipment</td>
<td>&nbsp;</td>
<td>GE Healthcare</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>BrA Enzyme and Buffer</td>
<td> Biotinylation Kit</td>
<td>Avidity</td>
<td>BIRA500</td>
<td>&nbsp;</td>
<tr>
<td>Ni-NTA Agarose Column</td>
<td>His Tag Protein Purification Column</td>
<td>GE Healthcare</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Desalting column</td>
<td> To get Rod of Salt from Protein</td>
<td>GE Healthcare</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>MonoQ Column</td>
<td>Anion Exchange Chromatgraphy</td>
<td>GE Healthcare</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>S200 Column</td>
<td> Size Exclusion Chromatography</td>
<td>GE Healthcare</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>alpha-Galcer</td>
<td> Glycolipid</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>PE- Streptavidin</td>
<td> For conjugating Protein</td>
<td>Molecular Probe</td>
<td> S-866</td>
<td>&nbsp;</td>		</tbody>
		</table>
		</div>

a method for production of recombinant mcd1d protein in insect cells.

CD1 proteins constitute a third class of antigen-presenting molecules. They are cell surface glycoproteins, expressed as approximately 50-kDa glycosylated heavy chains that are noncovalently associated with beta2-microglobulin. They bind lipids rather than peptides. Although their structure confirms the similarity of CD1 proteins to MHC class I and class II antigen presenting molecules, the mCD1d groove is relatively narrow, deep, and highly hydrophobic and it has two binding pockets instead of the several shallow pockets described for the classical MHC-encoded antigen-presenting molecules. Based upon their amino acid sequences, such a hydrobphobic groove provides an ideal environment for the binding of lipid antigens. The Natural Killer T (NKT) cells use their TCR to recognize glycolipids bound to or presented by CD1d. T cells reactive to lipids presented by CD1 have been involved in the protection against autoimmune and infectious diseases and in tumor rejection. Thus, the ability to identify, purify , and track the response of CD1-reactive NKT cell is of great importance . The generation of tetramers of alpha Galactosyl ceramide (a-Galcer) with CD1d has significant insight into the biology of NKT cells. Tetramers constructed from other CD1 molecules have also been generated and these new reagents have greatly expanded the knowledge of the functions of lipid-reactive T cells, with potential use in monitoring the response to lipid-based vaccines and in the diagnosis of autoimmune diseases and other treatments.

Watch this Scientific Journal Video about A Method For Production of Recombinant mCD1d Protein in Insect Cells. at JoVE.com

A Method For Production of Recombinant mCD1d Protein in Insect Cells.

A Method to prepare Insect cells and infect them with baculovirus for the the purpose of production of recombinant mCD1d proteinand generating mCD1d tetramers.

CD1 proteins constitute a third class of antigen-presenting molecules. They are cell surface glycoproteins, expressed as approximately 50-kDa glycosylated ...

a-method-for-production-of-recombinant-mcd1d-protein-in-insect-cells

Research

JoVE Journal

Biology

10.6K ビュー.  La Jolla Institute for Allergy and Immunology. 昆虫細胞を調製し、mCD1d四量体を生成する組換えmCD1d proteinandの生産を目的とバキュロウイルスとそれらを感染させる方法。

ビデオ: A Method For Production of Recombinant mCD1d Protein in Insect Cells.

A Method to prepare Insect cells and infect them with baculovirus for the the purpose of production of recombinant mCD1d  proteinand generating mCD1d...

microcrystallography of protein crystals and in cellulo diffraction

Microcrystallography of Protein Crystals and In Cellulo Diffraction

A protocol is presented for X-ray crystallography using protein microcrystals. Two examples analyzing in vivo-grown microcrystals after purification or in cellulo are...

Microcrystallography of Protein Crystals and In Cellulo Diffraction

efficient production and purification of recombinant murine kindlin-3 from insect cells for biophysical studies

Efficient Production and Purification of Recombinant Murine Kindlin-3 from Insect Cells for Biophysical Studies

Kindlins are fundamental to cell adhesion through integrins but studies of them have been hampered by the difficulty encountered in expressing them recombinantly in bacterial hosts. We describe here methods for their efficient production in baculovirus-infected insect...

a comparative analysis of recombinant protein expression in different biofactories: bacteria, insect cells and plant systems

A Comparative Analysis of Recombinant Protein Expression in Different Biofactories: Bacteria, Insect Cells and Plant Systems

In this study the expression of a target human recombinant protein in different production platforms was compared. We focused on traditional fermenter-based cultures and on plants, describing the set-up of each system and highlighting, on the basis of the reported results, the inherent limits and advantages for each...

transient expression and cellular localization of recombinant proteins in cultured insect cells

Transient Expression and Cellular Localization of Recombinant Proteins in Cultured Insect Cells

Nonlytic insect cell expression systems are underutilized for production, cellular trafficking/localization, and recombinant protein functional analysis. Here, we describe methods to generate expression vectors and subsequent transient protein expression in commercially available lepidopteran cell lines. The co-localization of Bemisia tabaci aquaporins with subcellular fluorescent marker proteins is also...

transient expression of foreign genes in insect cells (sf9) for protein functional assay

Transient Expression of Foreign Genes in Insect Cells sf9 for Protein Functional Assay

This protocol describes a heat shock-induced protein expression system (pDHsp/V5-His/sf9 cell system), which can be used for either expressing foreign proteins or evaluating the anti-apoptotic activity of potential foreign proteins and their truncated amino acids in insect...

Transient Expression of Foreign Genes in Insect Cells (sf9) for Protein Functional Assay

production and purification of recombinant antibodies from mammalian cells

The video explains the process of producing antibodies in mammalian host cells, from gene expression to secretion. It involves transcription, translation, signal recognition, correct folding, and eventual release into the extracellular medium via secretory...

Production and Purification of Recombinant Antibodies from Mammalian Cells

recombinant production of bifidobacterial endoglycosidases for n-glycan release

Recombinant Production of Bifidobacterial Endoglycosidases for N-glycan Release

Bifidobacteria possess a unique genomic capability for N-glycan cleavage. Recombinantly producing these enzymes would be a promising novel tool to release bioactive N-glycans from glycoprotein-rich substrates such as...

Recombinant Production of Bifidobacterial Endoglycosidases for N-glycan Release

recombinant retroviral production and infection of b cells

Recombinant Retroviral Production and Infection of B Cells

An efficient system of structure and function analysis of a gene in an ex vivo culture of splenic B-lymphocytes is described.  This method takes advantage of recombinant retroviral production in a helper free, ecotrophic packaging cell line. Stable, heritable expression of a gene of interest within primary lymphocytes is achieved leading to generation of surface antibodies on B cells undergoing class switch...

isolation of adeno-associated viral vectors through a single-step and semi-automated heparin affinity chromatography protocol

Author Spotlight: Improved Method for Production and Purification of Adeno-Associated Viral Vectors

This manuscript describes a detailed protocol for the generation and purification of adeno-associated viral vectors using an optimized heparin-based affinity chromatography method. It presents a simple, scalable, and cost-effective approach, eliminating the need for ultracentrifugation. The resulting vectors exhibit high purity and biological activity, proving their value in preclinical...

Purification of AAV Vectors by Single-Step Heparin Affinity Chromatography

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recombinant protein expression for structural biology in hek 293f suspension cells: a novel and accessible approach

Recombinant Protein Expression for Structural Biology in HEK 293F Suspension Cells: A Novel and Accessible Approach

The expression of recombinant proteins by mammalian systems is becoming an attractive method for producing protein complexes for structural biology. Here we present a simple yet highly efficient expression system using suspension grown mammalian cells to purify protein complexes for structural...

cation exchange chromatography: a technique to isolate target recombinant protein from insect cell lysate based on net surface charge

This video demonstrates the cation exchange chromatography technique to isolate recombinant protein from the insect cell protein...

Cation Exchange Chromatography: A Technique to Isolate Target Recombinant Protein from Insect Cell Lysate Based on Net Surface Charge

optimized production and analysis of recombinant protein-filled vesicles from e. coli

Author Spotlight: The Production of Recombinant Proteins 

The present protocol describes a detailed method for the bacterial production of recombinant proteins, including typically insoluble or disulfide-bond containing proteins, packaged inside extracellular membrane-bound vesicles. This has the potential to be applied to versatile areas of scientific research, including applied biotechnology and...

Optimized Production and Analysis of Recombinant Protein-Filled Vesicles from E. coli

production and titering of recombinant adeno-associated viral vectors

Production and Titering of Recombinant Adeno-associated Viral Vectors

Recombinant adeno-associated virus (rAAVs) vectors are becoming increasingly valuable for in vivo studies in animals. We describe how rAAVs can be produced in the laboratory and how these vectors can be titered to give an accurate reading of the number of infectious particles...

cell-free scaled production and adjuvant addition to a recombinant major outer membrane protein from chlamydia muridarum for vaccine development

Cell-Free Scaled Production and Adjuvant Addition to a Recombinant Major Outer Membrane Protein from Chlamydia muridarum for Vaccine Development

This protocol describes using commercial, cell-free protein expression kits to produce membrane proteins supported in nanodisc that can be used as antigens in subunit vaccines.

Cell-Free Scaled Production and Adjuvant Addition to a Recombinant Major Outer Membrane Protein from Chlamydia muridarum for Vaccine Development

Production and Imaging of Recombinant Protein-Filled Vesicles from &lt;em&gt;E. coli&lt;/em&gt;

insect puparium removal: a method for pupal investigation

This article describes a technique to remove an insect&#8217;s puparium while keeping the inside pupa intact and therefore fit for further investigation. The example protocol shows the procedure with Drosophila guttifera; however, this technique is applicable to other Drosophila...

Insect Puparium Removal: A Method for Pupal Investigation

Leave the mixture at room temperature for an additional 5 minutes. Add the entire mixture to the CHO cells while manually shaking the flask. Immediately incubate the cells at 37 degrees Celsius while shaking at 130...

apoplast-extraction based method to improve the purity of plant produced recombinant protein  

Author Spotlight: Optimizing Apoplast Protein Extraction for Efficient Recovery of Recombinant Proteins from Plant Cells

The purification of recombinant proteins from plant systems is usually challenged by plant proteins. This work provides a method to effectively extract and purify a secreted recombinant protein from the apoplast of Nicotiana...

Efficient Extraction and Purification of GFP-His from &lt;i&gt;N. benthamiana&lt;/i&gt; Leaves

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A Protocol for Phage Display and Affinity Selection Using Recombinant Protein Baits

Using recombinant phage as a scaffold to present various protein portions encoded by a directionally cloned cDNA library to immobilized bait molecules is an efficient means to discover interactions. The technique has largely been used to discover protein-protein interactions but the bait molecule to be challenged need not be restricted to proteins. The protocol presented here has been optimized to allow a modest number of baits to be screened in replicates to maximize the identification of independent clones presenting the same protein. This permits greater confidence that interacting proteins identified are legitimate interactors of the bait molecule. Monitoring the phage titer after each affinity selection round provides information on how the affinity selection is progressing as well as on the efficacy of negative controls. One means of titering the phage, and how and what to prepare in advance to allow this process to progress as efficiently as possible, is presented. Attributes of amplicons retrieved following isolation of independent plaque are highlighted that can be used to ascertain how well the affinity selection has progressed. Trouble shooting techniques to minimize false positives or to bypass persistently recovered phage are explained. Means of reducing viral contamination flare up are discussed.

Phage display is a powerful technique to capture proteins or protein moieties that interact with an immobilized molecule of interest. Once a decision of the type of phage cDNA library to create and screen has been made, the protocol described here permits efficient affinity selection leading to identification of interactors.

Using  recombinant phage as a scaffold to present various protein portions encoded by  a directionally cloned cDNA library to immobilized bait molecules ...

Kindlins are essential coactivators, with talin, of the cell surface receptors&#160;integrins and also participate in integrin outside-in signalling, and the control of gene transcription in the cell nucleus. The kindlins are ~75 kDa multidomain proteins and bind to an NPxY motif and upstream T/S cluster of the integrin &#946;-subunit cytoplasmic tail. The hematopoietically-important kindlin isoform, kindlin-3, is critical for platelet aggregation during thrombus formation, leukocyte rolling in response to infection and inflammation and osteoclast podocyte formation in bone resorption. Kindlin-3&#39;s role in these processes has resulted in extensive cellular and physiological studies. However, there is a need for an efficient method of acquiring high quality milligram quantities of the protein for further studies. We have developed a protocol, here described, for the efficient expression and purification of recombinant murine kindlin-3 by use of a baculovirus-driven expression system in Sf9 cells yielding sufficient amounts of high purity full-length protein to allow its biophysical characterization. The same approach could be taken in the study of the other mammalian kindlin isoforms.

Kindlins are fundamental to cell adhesion through integrins but studies of them have been hampered by the difficulty encountered in expressing them recombinantly in bacterial hosts. We describe here methods for their efficient production in baculovirus-infected insect cells.

Kindlins are essential coactivators, with talin, of the cell surface receptors&#160;integrins and also participate in integrin outside-in signalling, and ...

Investigating Protein-protein Interactions in Live Cells Using Bioluminescence Resonance Energy Transfer

Assays based on Bioluminescence Resonance Energy Transfer (BRET) provide a sensitive and reliable means to monitor protein-protein interactions in live cells. BRET is the non-radiative transfer of energy from a 'donor' luciferase enzyme to an 'acceptor' fluorescent protein. In the most common configuration of this assay, the donor is Renilla reniformis luciferase and the acceptor is Yellow Fluorescent Protein (YFP). Because the efficiency of energy transfer is strongly distance-dependent, observation of the BRET phenomenon requires that the donor and acceptor be in close proximity. To test for an interaction between two proteins of interest in cultured mammalian cells, one protein is expressed as a fusion with luciferase and the second as a fusion with YFP. An interaction between the two proteins of interest may bring the donor and acceptor sufficiently close for energy transfer to occur. Compared to other techniques for investigating protein-protein interactions, the BRET assay is sensitive, requires little hands-on time and few reagents, and is able to detect interactions which are weak, transient, or dependent on the biochemical environment found within a live cell. It is therefore an ideal approach for confirming putative interactions suggested by yeast two-hybrid or mass spectrometry proteomics studies, and in addition it is well-suited for mapping interacting regions, assessing the effect of post-translational modifications on protein-protein interactions, and evaluating the impact of mutations identified in patient DNA.

Interactions between proteins are fundamental to all cellular processes. Using Bioluminescence Resonance Energy Transfer, the interaction between a pair of proteins can be monitored in live cells and in real time. Furthermore, the effects of potentially pathogenic mutations can be assessed.

Assays based on Bioluminescence Resonance Energy Transfer (BRET) provide a sensitive and reliable means to monitor protein-protein interactions in live ...

The expression and purification of large amounts of recombinant protein complexes is an essential requirement for structural biology studies. For over two decades, prokaryotic expression systems such as E. coli have dominated the scientific literature over costly and less efficient eukaryotic cell lines. Despite the clear advantage in terms of yields and costs of expressing recombinant proteins in bacteria, the absence of specific co-factors, chaperones and post-translational modifications may cause loss of function, mis-folding and can disrupt protein-protein interactions of certain eukaryotic multi-subunit complexes, surface receptors and secreted proteins. The use of mammalian cell expression systems can address these drawbacks since they provide a eukaryotic expression environment. However, low protein yields and high costs of such methods have until recently limited their use for structural biology. Here we describe a simple and accessible method for expressing and purifying milligram quantities of protein by performing transient transfections of suspension grown HEK (Human Embryonic Kidney) 293F cells.

The expression of recombinant proteins by mammalian systems is becoming an attractive method for producing protein complexes for structural biology. Here we present a simple yet highly efficient expression system using suspension grown mammalian cells to purify protein complexes for structural studies.

The expression and purification of large amounts of recombinant protein complexes is an essential requirement for structural biology studies. For over two ...

Green Fluorescent Protein-based Expression Screening of Membrane Proteins in Escherichia coli

The production of recombinant membrane proteins for structural and functional studies remains technically challenging due to low levels of expression and the inherent instability of many membrane proteins once solubilized in detergents. A protocol is described that combines ligation independent cloning of membrane proteins as GFP fusions with expression in Escherichia coli detected by GFP fluorescence. This enables the construction and expression screening of multiple membrane protein/variants to identify candidates suitable for further investment of time and effort. The GFP reporter is used in a primary screen of expression by visualizing GFP fluorescence following SDS polyacrylamide gel electrophoresis (SDS-PAGE). Membrane proteins that show both a high expression level with minimum degradation as indicated by the absence of free GFP, are selected for a secondary screen. These constructs are scaled and a total membrane fraction prepared and solubilized in four different detergents. Following ultracentrifugation to remove detergent-insoluble material, lysates are analyzed by fluorescence detection size exclusion chromatography (FSEC). Monitoring the size exclusion profile by GFP fluorescence provides information about the mono-dispersity and integrity of the membrane proteins in different detergents. Protein: detergent combinations that elute with a symmetrical peak with little or no free GFP and minimum aggregation are candidates for subsequent purification. Using the above methodology, the heterologous expression in E. coli of SED (shape, elongation, division, and sporulation) proteins from 47 different species of bacteria was analyzed. These proteins typically have ten transmembrane domains and are essential for cell division. The results show that the production of the SEDs orthologues in E. coli was highly variable with respect to the expression levels and integrity of the GFP fusion proteins. The experiment identified a subset for further investigation.

Green Fluorescent Protein-based Expression Screening of Membrane Proteins in Escherichia coli

A streamlined approach to screening for the expression of recombinant membrane proteins in Escherichia coli based on fusion to green fluorescent protein is presented.

The production of recombinant membrane proteins for structural and functional studies remains technically challenging due to low levels of expression and ...

Plant-based systems are considered a valuable platform for the production of recombinant proteins as a result of their well-documented potential for the flexible, low-cost production of high-quality, bioactive products.
In this study, we compared the expression of a target human recombinant protein in traditional fermenter-based cell cultures (bacterial and insect) with plant-based expression systems, both transient and stable.
For each platform, we described the set-up, optimization and length of the production process, the final product quality and the yields and we evaluated provisional production costs, specific for the selected target recombinant protein.
Overall, our results indicate that bacteria are unsuitable for the production of the target protein due to its accumulation within insoluble inclusion bodies. On the other hand, plant-based systems are versatile platforms that allow the production of the selected protein at lower-costs than Baculovirus/insect cell system. In particular, stable transgenic lines displayed the highest-yield of the final product and transient expressing plants the fastest process development. However, not all recombinant proteins may benefit from plant-based systems but the best production platform should be determined empirically with a case-by-case approach, as described here.

In this study the expression of a target human recombinant protein in different production platforms was compared. We focused on traditional fermenter-based cultures and on plants, describing the set-up of each system and highlighting, on the basis of the reported results, the inherent limits and advantages for each platform.

Plant-based systems are considered a valuable platform for the production of recombinant proteins as a result of their well-documented potential for the ...

Nephrotoxin Microinjection in Zebrafish to Model Acute Kidney Injury

The kidneys are susceptible to harm from exposure to chemicals they filter from the bloodstream. This can lead to organ injury associated with a rapid decline in renal function and development of the clinical syndrome known as acute kidney injury (AKI). Pharmacological agents used to treat medical circumstances ranging from bacterial infection to cancer, when administered individually or in combination with other drugs, can initiate AKI. Zebrafish are a useful animal model to study the chemical effects on renal function in vivo, as they form an embryonic kidney comprised of nephron functional units that are conserved with higher vertebrates, including humans. Further, zebrafish can be utilized to perform genetic and chemical screens, which provide opportunities to elucidate the cellular and molecular facets of AKI and develop therapeutic strategies such as the identification of nephroprotective molecules. Here, we demonstrate how microinjection into the zebrafish embryo can be utilized as a paradigm for nephrotoxin studies.

Renal injuries incurred from nephrotoxins, which include drugs ranging from antibiotics to chemotherapeutics, can result in complex disorders whose pathogenesis remains incompletely understood. This protocol demonstrates how zebrafish can be used for disease modeling of these conditions, which can be applied to the identification of renoprotective measures.

The kidneys are susceptible to harm from exposure to chemicals they filter from the bloodstream. This can lead to organ injury associated with a rapid ...

A Graphical User Interface for Software-assisted Tracking of Protein Concentration in Dynamic Cellular Protrusions

Filopodia are dynamic, finger-like cellular protrusions associated with migration and cell-cell communication. In order to better understand the complex signaling mechanisms underlying filopodial initiation, elongation and subsequent stabilization or retraction, it is crucial to determine the spatio-temporal protein activity in these dynamic structures. To analyze protein function in filopodia, we recently developed a semi-automated tracking algorithm that adapts to filopodial shape-changes, thus allowing parallel analysis of protrusion dynamics and relative protein concentration along the whole filopodial length. Here, we present a detailed step-by-step protocol for optimized cell handling, image acquisition and software analysis. We further provide instructions for the use of optional features during image analysis and data representation, as well as troubleshooting guidelines for all critical steps along the way. Finally, we also include a comparison of the described image analysis software with other programs available for filopodia quantification. Together, the presented protocol provides a framework for accurate analysis of protein dynamics in filopodial protrusions using image analysis software.

We present a software solution for semi-automated tracking of relative protein concentration along the length of dynamic cellular protrusions.

Filopodia are dynamic, finger-like cellular protrusions associated with migration and cell-cell communication. In order to better understand the complex ...

Heterologous protein expression systems are used for the production of recombinant proteins, the interpretation of cellular trafficking/localization, and the determination of the biochemical function of proteins at the sub-organismal level. Although baculovirus expression systems are increasingly used for protein production in numerous biotechnological, pharmaceutical, and industrial applications, nonlytic systems that do not involve viral infection have clear benefits but are often overlooked and underutilized. Here, we describe a method for generating nonlytic expression vectors and transient recombinant protein expression. This protocol allows for the efficient cellular localization of recombinant proteins and can be used to rapidly discern protein trafficking within the cell. We show the expression of four&#160;recombinant proteins in a commercially available insect cell line, including two aquaporin proteins from the insect Bemisia tabaci, as well as subcellular marker proteins specific for the cell plasma membrane and for intracellular lysosomes. All recombinant proteins were produced as chimeras with fluorescent protein markers at their carboxyl termini, which allows for the direct detection of the recombinant proteins. The double transfection of cells with plasmids harboring constructs for the genes of interest and a known subcellular marker allows for live cell imaging and improved validation of cellular protein localization.

Nonlytic insect cell expression systems are underutilized for production, cellular trafficking/localization, and recombinant protein functional analysis. Here, we describe methods to generate expression vectors and subsequent transient protein expression in commercially available lepidopteran cell lines. The co-localization of Bemisia tabaci aquaporins with subcellular fluorescent marker proteins is also presented.

Heterologous protein expression systems are used for the production of recombinant proteins, the interpretation of cellular trafficking/localization, and ...

This innovative system, using a short peptide tag, that exports multiple recombinant proteins in membrane bound vesicles from E. coli, provides an effective solution to a range of problems associated with bacterial recombinant protein expression. These recombinant vesicles compartmentalise proteins within a micro-environment that facilitates the production of otherwise challenging, toxic, insoluble, or disulfide-bond containing proteins from bacteria. Protein yield is increased considerably when compared to typical bacterial expression in the absence of the vesicle-nucleating peptide tag. The release of vesicle-packaged proteins supports isolation from the culture medium&#160;and permits long-term active protein storage. This technology gives rise to increased yields of vesicle-packaged, functional proteins for simplified downstream processing for a diverse range of applications from applied biotechnology to discovery science and medicine. In the present article and the associated video, a detailed protocol of the method is provided, which highlights key steps in the methodology to maximize recombinant protein-filled vesicle production.

The present protocol describes a detailed method for the bacterial production of recombinant proteins, including typically insoluble or disulfide-bond containing proteins, packaged inside extracellular membrane-bound vesicles. This has the potential to be applied to versatile areas of scientific research, including applied biotechnology and medicine.