Name: double fluorescence in situ hybridization in fresh brain sections
Uploaded: 2010-08-14T17:00:00
Description: Watch this Scientific Journal Video about Double Fluorescence in situ Hybridization in Fresh Brain Sections at JoVE.com

Work supported by grants of NIH/NIDCD and the Schmitt Foundation to RP.

This protocol was developed and refined based on standard radioactive and non-radioactive in-situ hybridization methods, previously developed by us and others to detect one or two transcript species in brain tissue 1-7. The protocol described below has a total length of 2 or 3 days, depending on the number of procedural interruptions chosen by the end user. All steps detailed below are to be conducted at room temperature, with the exception of the riboprobe hybridization step and post-hybridization wa...

<ol>
	<li>Jin, L., Lloyd, R. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+hybridization:+methods+and+applications.">In situ hybridization: methods and applications.</a> J Clin Lab Anal. 11, 2-9 (1997).</li><li>Stoler, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+hybridization.">In situ hybridization.</a> Clin Lab Med. 10, 215-236 (1990).</li><li>Komminoth, P., Werner, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Target+and+signal+amplification:+approaches+to+increase+the+sensitivity+of+in+situ+hybridization.">Target and signal amplification: approaches to increase the sensitivity of in situ hybridization.</a> Histochem Cell Biol. 108, 325-3233 (1997).</li><li>Kessler, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+digoxigenin:anti-digoxigenin+(DIG)+technology--a+survey+on+the+concept+and+realization+of+a+novel+bioanalytical+indicator+system.">The digoxigenin:anti-digoxigenin (DIG) technology--a survey on the concept and realization of a novel bioanalytical indicator system.</a> Mol Cell Probes. 5, 161-205 (1991).</li><li>Panoskaltsis-Mortari, A., Bucy, R. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+hybridization+with+digoxigenin-labeled+RNA+probes:+facts+and+artifacts.">In situ hybridization with digoxigenin-labeled RNA probes: facts and artifacts.</a> Biotechniques. 18, 300-307 (1995).</li><li>Qian, X., Lloyd, R. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+developments+in+signal+amplification+methods+for+in+situ+hybridization.">Recent developments in signal amplification methods for in situ hybridization.</a> Diagn Mol Pathol. 12, 1-13 (2003).</li><li>Mello, C. V., Jarvis, E. D., Denisenko, N., Rivas, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+of+song-regulated+genes+in+the+brain+of+songbirds.">Isolation of song-regulated genes in the brain of songbirds.</a> Methods Mol Biol. 85, 205-217 (1997).</li><li>Pinaud, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=GABAergic+neurons+participate+in+the+brain's+response+to+birdsong+auditory+stimulation.">GABAergic neurons participate in the brain's response to birdsong auditory stimulation.</a> Eur J Neurosci. 20, 1318-1330 (2004).</li><li>Velho, T. A., Pinaud, R., Rodrigues, P. V., Mello, C. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Co-induction+of+activity-dependent+genes+in+songbirds.">Co-induction of activity-dependent genes in songbirds.</a> Eur J Neurosci. 22, 1667-1678 (2005).</li><li>Tremere, L. A., Jeong, J. K., Pinaud, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Estradiol+shapes+auditory+processing+in+the+adult+brain+by+regulating+inhibitory+transmission+and+plasticity-associated+gene+expression.">Estradiol shapes auditory processing in the adult brain by regulating inhibitory transmission and plasticity-associated gene expression.</a> J Neurosci. 29, 5949-5963 (2009).</li><li>Pinaud, R., Mello, C. V., Velho, T. A., Wynne, R. D., Tremere, L. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detection+of+two+mRNA+species+at+single-cell+resolution+by+double-fluorescence+in+situ+hybridization.">Detection of two mRNA species at single-cell resolution by double-fluorescence in situ hybridization.</a> Nat Protoc. 3, 1370-1379 (2008).</li><li>Pinaud, R., Jeong, J. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Duplex+fluorescence+in+situ+hybridization+in+the+study+of+gene+co-regulation+in+the+vertebrate+brain.+Methods+Mol+Biol.">Duplex fluorescence in situ hybridization in the study of gene co-regulation in the vertebrate brain. Methods Mol Biol.</a> 611, 115-129 (2010).</li></ol>

We have used this protocol to study how the vertebrate brain is neurochemically and functionally organized, and to determine how behaviorally-relevant sensory stimuli impact the genomic machinery of neurons in the adult brain 8-10. We have successfully used this method in brain tissue from mice, rats and songbirds, but anticipate that this protocol will be easily adaptable to brain sections obtained from an array of vertebrate species and, perhaps, non-neural tissues. Key controls required to obtaining reliabl...

<!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>DEPC</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>IC15090225</td>
<td>toxic substance</td>
</tr>
<tr>
<td>PCR purification kit</td>
<td>&nbsp;</td>
<td>QIAgen</td>
<td>28104</td>
<td>&nbsp;</td>
<tr>
<td>Formaldehyde</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>BDH0506-4LP
</td>
<td>toxic substance</td>
</tr>
<tr>
<td>T3 RNA polymerase</td>
<td>&nbsp;</td>
<td>Roche</td>
<td>11031163001</td>
<td>&nbsp;</td>
<tr>
<td>T7 RNA polymerase</td>
<td>&nbsp;</td>
<td>Roche</td>
<td>10881767001</td>
<td>&nbsp;</td>
<tr>
<td>Tris-HCl (1 M, pH 7.5)</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>IC816124</td>
<td>&nbsp;</td>
<tr>
<td>MgCl2 (1 M)</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>449172</td>
<td>&nbsp;</td>
<tr>
<td>Spermidine (1 M)</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>S0266</td>
<td>&nbsp;</td>
<tr>
<td>DIG RNA labeling mix</td>
<td>&nbsp;</td>
<td>Roche</td>
<td>NC9380805</td>
<td>&nbsp;</td>
<tr>
<td>Biotin RNA labeling mix</td>
<td>&nbsp;</td>
<td>Roche</td>
<td>NC9440104</td>
<td>&nbsp;</td>
<tr>
<td>RNasin</td>
<td>&nbsp;</td>
<td>Promega</td>
<td>N2111</td>
<td>&nbsp;</td>
<tr>
<td>BSA</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>05491</td>
<td>&nbsp;</td>
<tr>
<td>DTT</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>D5545</td>
<td>&nbsp;</td>
<tr>
<td>Sephadex G50</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>95016-772</td>
<td>&nbsp;</td>
<tr>
<td>EDTA</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>101384-758</td>
<td>&nbsp;</td>
<tr>
<td>SDS</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>L4390</td>
<td>&nbsp;</td>
<tr>
<td>Transfer (t)RNA</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>15401011</td>
<td>&nbsp;</td>
<tr>
<td>10X MOPS</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>14221-398</td>
<td>toxic substance</td>
</tr>
<tr>
<td>Paraformaldehyde</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>AAAL04737-36</td>
<td>toxic substance</td>
</tr>
<tr>
<td>Sodium phosphate monobasic</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>S3139</td>
<td>&nbsp;</td>
<tr>
<td>Sodium phosphate dibasic</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>S3264</td>
<td>&nbsp;</td>
<tr>
<td>NaOH</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>SX0600-1</td>
<td>&nbsp;</td>
<tr>
<td>Triethanolamine</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>IC15216391</td>
<td>&nbsp;</td>
<tr>
<td>Acetic anhydride</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>MK242002</td>
<td>toxic substance</td>
</tr>
<tr>
<td>SSPE</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>82021-488</td>
<td>&nbsp;</td>
<tr>
<td>Formamide</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>JT4028-1</td>
<td>toxic substance</td>
</tr>
<tr>
<td>Poly A</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>POLYA.GF</td>
<td>&nbsp;</td>
<tr>
<td>Mineral oil</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>IC15169491</td>
<td>&nbsp;</td>
<tr>
<td>Chloroform</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>BDH1109</td>
<td>organic solvent</td>
</tr>
<tr>
<td>Deionized formamide</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>F9037</td>
<td>toxic substance</td>
</tr>
<tr>
<td>Hydrogen peroxide</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>VW36901</td>
<td>toxic substance</td>
</tr>
<tr>
<td>Tween 20</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>P1379</td>
<td>&nbsp;</td>
<tr>
<td>Triton X-100</td>
<td>&nbsp;</td>
<td>J. T. Baker</td>
<td>X198-05</td>
<td>&nbsp;</td>
<tr>
<td>Anti-DIG HRP</td>
<td>&nbsp;</td>
<td>Roche</td>
<td>11093274910</td>
<td>&nbsp;</td>
<tr>
<td>Anti-biotin peroxidase</td>
<td>&nbsp;</td>
<td>Vector</td>
<td>SP3010</td>
<td>&nbsp;</td>
<tr>
<td>TSA Alexa Fluor 594</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>T20935</td>
<td>&nbsp;</td>
<tr>
<td>TSA Alexa Fluor 488</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>T20932</td>
<td>&nbsp;</td>
<tr>
<td>Hoechst</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>200025-538</td>
<td>&nbsp;</td>
<tr>
<td>Vectashield</td>
<td>&nbsp;</td>
<td>Vector</td>
<td>H-1000</td>
<td>&nbsp;</td>
<tr>
<td>embedding mold</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>15160-157</td>
<td>&nbsp;</td>
<tr>
<td>cryostat</td>
<td>&nbsp;</td>
<td>Leica</td>
<td>CM 1850</td>
<td>&nbsp;</td>
<tr>
<td>Superfrost plus slide</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>89033-052</td>
<td>&nbsp;</td>		</tbody>
		</table>
		</div>
			<div>
			Solutions
<ol>
	<li>Column washing buffer: 10 mM Tris-HCl, 0.15 M NaCl, 0.05 mM EDTA, 50 &mu;g/&mu;l tRNA, 0.1% SDS in 50 ml DEPC-treated water.</li>
	<li>Column blocking buffer: 10 mM Tris-HCl, 50 mM NaCl, 0.1 mM EDTA in 50 ml DEPC-treated water.</li>
	<li>TNT buffer: 60 ml of 1 M Tris-HCl, 18 ml of 5 M NaCl and 1.8 ml of Triton X-100 in 600 ml of DEPC-treated water.</li>
	<li>TNB buffer: 100 mM Tris-HCl, 8.3 &mu;g/&mu;l BSA, 0.15 M NaCl and 3% Triton X-100 in DEPC-treated water.</li>
	<li>TE buffer: 10 mM Tris-HCl, pH 7.5 plus 1 mM EDTA, pH 7.5.</li>
	<li>Acetylation solution: 2.7 ml of triethanolamine plus 0.5 ml of acetic anhydride in 200 ml of DEPC-treated water.</li>
	<li>Hybridization solution: 50% formamide, 2X SSPE, 2 &mu;g/&mu;l tRNA, 1 &mu;g/&mu;l BSA and 1 &mu;g/&mu;l poly A in DEPC-treated water. It needs 16 l per section.</li>
</ol>		</div>

double fluorescence in situ hybridization in fresh brain sections

Here we describe a modified version of a double fluorescence in situ hybridization (dFISH) method optimized for detecting two mRNAs of interest in fresh frozen brain sections. Our group has successfully used this approach to study gene co-regulation. More specifically, we have used this dFISH method to explore the anatomical organization, neurochemical properties, and the impact of sensory experience in central sensory circuits, at single cell resolution. This protocol has been validated in brain tissue from mice, rats and songbirds but is expected to be easily adaptable to other vertebrate species, as well as to an array of non-neural tissues. In this film we provide a detailed demonstration of the main steps of this procedure.

Watch this Scientific Journal Video about Double Fluorescence in situ Hybridization in Fresh Brain Sections at JoVE.com

Double Fluorescence in situ Hybridization in Fresh Brain Sections

This protocol involves a non-radioactive in-situ hybridization procedure that enables the simultaneous identification of two transcript species, at a single cell resolution, in thin sections of the vertebrate brain.

Double Fluorescence in situ Hybridization in Fresh Brain Sections

Here we describe a modified version of a double fluorescence in situ hybridization (dFISH) method optimized for detecting two mRNAs of interest in fresh ...

double-fluorescence-in-situ-hybridization-in-fresh-brain-sections

Research

JoVE Journal

Neuroscience

Combining Lipophilic dye, in situ Hybridization, Immunohistochemistry, and Histology

Going beyond single gene function to cut deeper into gene regulatory networks requires multiple mutations combined in a single animal. Such analysis of two or more genes needs to be complemented with in situ hybridization of other genes, or immunohistochemistry of their proteins, both in whole mounted developing organs or sections for detailed resolution of the cellular and tissue expression alterations. Combining multiple gene alterations requires the use of cre or flipase to conditionally delete genes and avoid embryonic lethality. Required breeding schemes dramatically enhance effort and cost proportional to the number of genes mutated, with an outcome of very few animals with the full repertoire of genetic modifications desired. Amortizing the vast amount of effort and time to obtain these few precious specimens that are carrying multiple mutations necessitates tissue optimization. Moreover, investigating a single animal with multiple techniques makes it easier to correlate gene deletion defects with expression profiles. We have developed a technique to obtain a more thorough analysis of a given animal; with the ability to analyze several different histologically recognizable structures as well as gene and protein expression all from the same specimen in both whole mounted organs and sections. Although mice have been utilized to demonstrate the effectiveness of this technique it can be applied to a wide array of animals. To do this we combine lipophilic dye tracing, whole mount in situ hybridization, immunohistochemistry, and histology to extract the maximal possible amount of data.

Combining Lipophilic dye, in situ Hybridization, Immunohistochemistry, and Histology

A combination of different techniques to maximize data collection from mouse tissue is presented.

Going beyond single gene function to cut deeper into gene regulatory networks requires multiple mutations combined in a single animal.  Such analysis of ...

Complete Spinal Cord Injury and Brain Dissection Protocol for Subsequent Wholemount In Situ Hybridization in Larval Sea Lamprey

After a complete spinal cord injury, sea lampreys at first are paralyzed below the level of transection. However, they recover locomotion after several weeks, and this is accompanied by short distance regeneration (a few mm) of propriospinal axons and spinal-projecting axons from the brainstem. Among the 36 large identifiable spinal-projecting neurons, some are good regenerators and others are bad regenerators. These neurons can most easily be identified in wholemount CNS preparations. In order to understand the neuron-intrinsic mechanisms that favor or inhibit axon regeneration after injury in the vertebrates CNS, we determine differences in gene expression between the good and bad regenerators, and how expression is influenced by spinal cord transection. This paper illustrates the techniques for housing larval and recently transformed adult sea lampreys in fresh water tanks, producing complete spinal cord transections under microscopic vision, and preparing brain and spinal cord wholemounts for in situ hybridization. Briefly, animals are kept at 16&#160;&#176;C and anesthetized in 1% Benzocaine in lamprey Ringer. The spinal cord is transected with iridectomy scissors via a dorsal approach and the animal is allowed to recover in fresh water tanks at 23 &#176;C. For in situ hybridization, animals are reanesthetized and the brain and cord removed via a dorsal approach.

Complete Spinal Cord Injury and Brain Dissection Protocol for Subsequent Wholemount In Situ Hybridization in Larval Sea Lamprey

Lampreys recover locomotion after a complete spinal cord injury. However, some spinal-projecting neurons are good regenerators and others are not. This paper illustrates the techniques for housing sea lamprey larvae (and recently transformed adults), producing complete spinal cord transections and preparing wholemount brains and spinal cords for in situ hybridization.

After a complete spinal cord injury, sea lampreys at first are paralyzed below the level of transection. However, they recover locomotion after several ...

Detection of Axonally Localized mRNAs in Brain Sections Using High-Resolution In Situ Hybridization

mRNAs are frequently localized to vertebrate axons and their local translation is required for axon pathfinding or branching during development and for maintenance, repair or neurodegeneration in postdevelopmental periods. High throughput analyses have recently revealed that axons have a more dynamic and complex transcriptome than previously expected. These analysis, however have been mostly done in cultured neurons where axons can be isolated from the somato-dendritic compartments. It is virtually impossible to achieve such isolation in whole tissues in vivo. Thus, in order to verify the recruitment of mRNAs and their functional relevance in a whole animal, transcriptome analyses should ideally be combined with techniques that allow the visualization of mRNAs in situ. Recently, novel ISH technologies that detect RNAs at a single-molecule level have been developed. This is especially important when analyzing the subcellular localization of mRNA, since localized RNAs are typically found at low levels. Here we describe two protocols for the detection of axonally-localized mRNAs using a novel ultrasensitive RNA ISH technology. We have combined RNAscope ISH with axonal counterstain using fluorescence immunohistochemistry or histological dyes to verify the recruitment of Atf4 mRNA to axons in vivo in the mature mouse and human brains.

Detection of Axonally Localized mRNAs in Brain Sections Using High-Resolution In Situ Hybridization

RNA in situ hybridization (ISH) enables the visualization of RNAs in cells and tissues. Here we show how combination of RNAscope ISH with immunohistochemistry or histological dyes can be successfully used to detect mRNAs localized to axons in sections of mouse and human brains.

mRNAs are frequently localized to vertebrate axons and their local translation is required for axon pathfinding or branching during development and for ...

Double-barreled and Concentric Microelectrodes for Measurement of Extracellular Ion Signals in Brain Tissue

Electrical activity in the brain is accompanied by significant ion fluxes across membranes, resulting in complex changes in the extracellular concentration of all major ions. As these ion shifts bear significant functional consequences, their quantitative determination is often required to understand the function and dysfunction of neural networks under physiological and pathophysiological conditions. In the present study, we demonstrate the fabrication and calibration of double-barreled ion-selective microelectrodes, which have proven to be excellent tools for such measurements in brain tissue. Moreover, so-called &#8220;concentric&#8221; ion-selective microelectrodes are also described, which, based on their different design, offer a far better temporal resolution of fast ion changes. We then show how these electrodes can be employed in acute brain slice preparations of the mouse hippocampus. Using double-barreled, potassium-selective microelectrodes, changes in the extracellular potassium concentration ([K+]o) in response to exogenous application of glutamate receptor agonists or during epileptiform activity are demonstrated. Furthermore, we illustrate the response characteristics of sodium-sensitive, double-barreled and concentric electrodes and compare their detection of changes in the extracellular sodium concentration ([Na+]o) evoked by bath or pressure application of drugs. These measurements show that while response amplitudes are similar, the concentric sodium microelectrodes display a superior signal-to-noise ratio and response time as compared to the double-barreled design. Generally, the demonstrated procedures will be easily transferable to measurement of other ions species, including pH or calcium, and will also be applicable to other preparations.

We demonstrate the fabrication, calibration and properties of two types of ion-selective microelectrodes (double-barreled and concentric) for measurement of ion concentrations in brain tissue. These are then used in the mouse hippocampal slice preparation to show that excitatory activity changes both extracellular potassium and sodium concentrations.

Electrical activity in the brain is accompanied by significant ion fluxes across membranes, resulting in complex changes in the extracellular ...

Rapid In Situ Hybridization using Oligonucleotide Probes on Paraformaldehyde-prefixed Brain of Rats with Serotonin Syndrome

3,4-Methylenedioxymethamphetamine (MDMA; ecstasy) toxicity may cause region-specific changes in serotonergic mRNA expression due to acute serotonin (5-hydroxytryptamine; 5-HT) syndrome. This hypothesis can be tested using in situ hybridization to detect the serotonin 5-HT2A receptor gene htr2a. In the past, such procedures, utilizing radioactive riboprobe, were difficult because of the complicated workflow that needs several days to perform and the added difficulty that the technique required the use of fresh frozen tissues maintained in an RNase-free environment. Recently, the development of short oligonucleotide probes has simplified in situ hybridization procedures and allowed the use of paraformaldehyde-prefixed brain sections, which are more widely available in laboratories. Here, we describe a detailed protocol using non-radioactive oligonucleotide probes on the prefixed brain tissues. Hybridization probes used for this study include dapB (a bacterial gene coding for dihydrodipicolinate reductase), ppiB (a housekeeping gene coding for peptidylprolyl isomerase B), and htr2a (a serotonin gene coding for 5-HT2A receptors). This method is relatively simply, cheap, reproducible and requires less than two days to complete.

Rapid In Situ Hybridization using Oligonucleotide Probes on Paraformaldehyde-prefixed Brain of Rats with Serotonin Syndrome

This protocol describes a rapid and simplified in situ hybridization method ideal forparaformaldehyde-prefixed brain, thus reducing the need for prolonged complex steps while using fresh frozen tissues. The method is validated using the identification of the serotonin 5-HT2A receptor gene htr2a in rats.

3,4-Methylenedioxymethamphetamine (MDMA; ecstasy) toxicity may cause region-specific changes in serotonergic mRNA expression due to acute serotonin ...

Combining Double Fluorescence In Situ Hybridization with Immunolabelling for Detection of the Expression of Three Genes in Mouse Brain Sections

Detection of gene expression in different types of brain cells e.g., neurons, astrocytes, oligodendrocytes, oligodendrocyte precursors and microglia, can be hampered by the lack of specific primary or secondary antibodies for immunostaining. Here we describe a protocol to detect the expression of three different genes in the same brain section using double fluorescence in situ hybridization with two gene-specific probes followed by immunostaining with an antibody of high specificity directed against the protein encoded by a third gene. The Aspartoacyclase (ASPA) gene, mutations of which can lead to a rare human white matter disease - Canavan disease - is thought to be expressed in oligodendrocytes and microglia but not in astrocytes and neurons. However, the precise expression pattern of ASPA in the brain has yet to be established. This protocol has allowed us to determine that ASPA is expressed in a subset of mature oligodendrocytes and it can be generally applied to a wide range of gene expression pattern studies.

Combining Double Fluorescence In Situ Hybridization with Immunolabelling for Detection of the Expression of Three Genes in Mouse Brain Sections

Localizing gene expression to specific cell types can be challenging due to the lack of specific antibodies. Here we describe a protocol for simultaneous triple detection of gene expression by combining double fluorescence RNA in situ hybridization with immunostaining.

Detection of gene expression in different types of brain cells e.g., neurons, astrocytes, oligodendrocytes, oligodendrocyte precursors and microglia, can ...

Localization of Odorant Receptor Genes in Locust Antennae by RNA In Situ Hybridization

Insects have evolved sophisticated olfactory reception systems to sense exogenous chemical signals. These chemical signals are transduced by Olfactory Receptor Neurons (ORNs) housed in hair-like structures, called chemosensilla, of the antennae. On the ORNs&#39; membranes, Odorant Receptors (ORs) are believed to be involved in odor coding. Thus, being able to identify genes localized to the ORNs is necessary to recognize OR genes, and provides a fundamental basis for further functional in situ studies. The RNA expression levels of specific ORs in insect antennae are very low, and preserving insect tissue for histology is challenging. Thus, it is difficult to localize an OR to a specific type of sensilla using RNA in situ hybridization. In this paper, a detailed and highly effective RNA in situ hybridization protocol particularly for lowly expressed OR genes of insects, is introduced. In addition, a specific OR gene was identified by conducting double-color fluorescent in situ hybridization experiments using a co-expressing receptor gene, Orco, as a marker.

Localization of Odorant Receptor Genes in Locust Antennae by RNA In Situ Hybridization

This paper describes a detailed and highly effective RNA in situ hybridization protocol particularly for low-level expressed Odorant Receptor (OR) genes, as well as other genes, in insect antennae using digoxigenin (DIG)-labeled or biotin-labeled probes.

Insects have evolved sophisticated olfactory reception systems to sense exogenous chemical signals. These chemical signals are transduced by Olfactory ...

Isolation of Cerebral Capillaries from Fresh Human Brain Tissue

Understanding blood-brain barrier function under physiological and pathophysiological conditions is critical for the development of new therapeutic strategies that hold the promise to enhance brain drug delivery, improve brain protection, and treat brain disorders. However, studying the human blood-brain barrier function is challenging. Thus, there is a critical need for appropriate models. In this regard, brain capillaries isolated from human brain tissue represent a unique tool to study barrier function as close to the human in vivo situation as possible. Here, we describe an optimized protocol to isolate capillaries from human brain tissue at a high yield and with consistent quality and purity. Capillaries are isolated from fresh human brain tissue using mechanical homogenization, density-gradient centrifugation, and filtration. After the isolation, the human brain capillaries can be used for various applications including leakage assays, live cell imaging, and immune-based assays to study protein expression and function, enzyme activity, or intracellular signaling. Isolated human brain capillaries are a unique model to elucidate the regulation of the human blood-brain barrier function. This model can provide insights into central nervous system (CNS) pathogenesis, which will help the development of therapeutic strategies for treating CNS disorders.

Isolated brain capillaries from human brain tissue can be used as a preclinical model to study barrier function under physiological and pathophysiological conditions. Here, we present an optimized protocol to isolate brain capillaries from fresh human brain tissue.

Understanding blood-brain barrier function under physiological and pathophysiological conditions is critical for the development of new therapeutic ...

Combining Multiplex Fluorescence In Situ Hybridization with Fluorescent Immunohistochemistry on Fresh Frozen or Fixed Mouse Brain Sections

Fluorescent in situ hybridization (FISH) is a molecular technique that identifies the presence and spatial distribution of specific RNA transcripts within cells. Neurochemical phenotyping of functionally identified neurons usually requires concurrent labelling with multiple antibodies (targeting protein) using immunohistochemistry (IHC) and optimization of in situ hybridization (targeting RNA), in tandem. A &#34;neurochemical signature&#34; to characterize particular neurons may be achieved however complicating factors include the need to verify FISH and IHC targets before combining the methods, and the limited number of RNAs and proteins that may be targeted simultaneously within the same tissue section.
Here we describe a protocol, using both fresh frozen and fixed mouse brain preparations, which detects multiple mRNAs and proteins in the same brain section using RNAscope FISH followed by fluorescence immunostaining, respectively. We use the combined method to describe the expression pattern of low abundance mRNAs (e.g., galanin receptor 1) and high abundance mRNAs (e.g., glycine transporter 2), in immunohistochemically identified brainstem nuclei.
Key considerations for protein labelling downstream of the FISH assay extend beyond tissue preparation and optimization of FISH probe labelling. For example, we found that antibody binding and labelling specificity can be detrimentally affected by the protease step within the FISH probe assay. Proteases catalyze hydrolytic cleavage of peptide bonds, facilitating FISH probe entry into cells, however they may also digest the protein targeted by the subsequent IHC assay, producing off target binding. The subcellular location of the targeted protein is another factor contributing to IHC success following FISH probe assay. We observed IHC specificity to be retained when the targeted protein is membrane bound, whereas IHC targeting cytoplasmic protein required extensive troubleshooting. Finally, we found handling of slide-mounted fixed frozen tissue more challenging than fresh frozen tissue, however IHC quality was overall better with fixed frozen tissue, when combined with RNAscope.

Combining Multiplex Fluorescence In Situ Hybridization with Fluorescent Immunohistochemistry on Fresh Frozen or Fixed Mouse Brain Sections

This protocol describes a method for combining fluorescence in situ hybridization (FISH) and fluorescence immunohistochemistry (IHC) in both fresh frozen and fixed mouse brain sections, with the goal of achieving multilabel FISH and fluorescence IHC signal. IHC targeted cytoplasmic and membrane attached proteins.

Fluorescent in situ hybridization (FISH) is a molecular technique that identifies the presence and spatial distribution of specific RNA transcripts within ...

A Rat Model of EcoHIV Brain Infection

It has been well studied that the EcoHIV infected mouse model is of significant utility in investigating HIV associated neurological complications. Establishment of the EcoHIV infected rat model for studies of drug abuse and neurocognitive disorders, would be beneficial in the study of neuroHIV and HIV-1 associated neurocognitive disorders (HAND). In the present study, we demonstrate the successful creation of a rat model of active HIV infection using chimeric HIV (EcoHIV). First, the lentiviral construct of EcoHIV was packaged in cultured 293 FT cells for 48 hours. Then, the conditional medium was concentrated and titered. Next, we performed bilateral stereotaxic injections of the EcoHIV-EGFP into F344/N rat brain tissue. One week after infection, EGFP fluorescence signals were detected in the infected brain tissue, indicating that EcoHIV successfully induces an active HIV infection in rats. In addition, immunostaining for the microglial cell marker, Iba1, was performed. The results indicated that microglia were the predominant cell type harboring EcoHIV. Furthermore, EcoHIV rats exhibited alterations in temporal processing, a potential underlying neurobehavioral mechanism of HAND as well as synaptic dysfunction eight weeks after infection. Collectively, the present study extends the EcoHIV model of HIV-1 infection to the rat offering a valuable biological system to study HIV-1 viral reservoirs in the brain as well as HAND and associated comorbidities such as drug abuse.

Here, we present a protocol to establish a new rat model of active HIV infection using chimeric HIV (EcoHIV), which is critical for enhancing our understanding of HIV-1 viral reservoirs in the brain and offering a system to study HIV-associated neurocognitive disorders and associated comorbidities (i.e., drug abuse).

It has been well studied that the EcoHIV infected mouse model is of significant utility in investigating HIV associated neurological complications. ...