Agradecemos N. Sawtell (Hospital Medical Center de Cincinnati Children, Cincinnati, Ohio, EUA), S. Efstathiou (University of Cambridge, Reino Unido) e James Hill (LSU Health Sciences Center, New Orleans, EUA) para fornecer amostras de HSV-1 infectados ratinhos e coelhos, respectivamente, e para reagentes; H. Masumoto (Instituto Kazusa DNA Research, Chiba, Japão) e S. Khochbin (Institut Albert Bonniot, Grenoble, França) para discussões úteis. Este trabalho foi financiado por doações do Centre National de la Recherche Scientifique (CNRS) (programa ATIP, para PL, http://www.cnrs.fr), a Agência Nacional Francesa de Pesquisa (ANR) (ANR-05-MIIM- 008-01, CENTROLAT, <a href="http://www.agencenationale-recherche.fr">http://www.agencenationale-recherche.fr</a> ), a Fundação FINOVI ( <a href="http://www.finovi.org/:fr:start">http://www.finovi.org/:fr:start</a> ), o Labex DEVweCAN (ANR-10-LabX-61 ) da Université de Lyon, dentro do programa &quot;Investissements d&#39;Avenir &quot;(ANR-11-IDEX-0007) operado pela ANR ( <a href="http://www.agence-nationale-recherche.fr">http://www.agence-nationale-recherche.fr</a> ), l&#39;Association pour la Recherche contre le Cancer (ARC-7979 e ARC- 4910, <a href="http://www.arc-cancer.net">http://www.arc-cancer.net</a> ), la Ligue Nationale Contre le Câncer (LNCC, <a href="http://www.ligue-cancer.net">http://www.ligue-cancer.net</a> ) e Inca (programa EPIPRO, <a href="http://www.e-cancer.fr">http://www.e -cancer.fr</a> ). FC e PL são pesquisadores do CNRS.

Os autores declaram não haver interesses financeiros concorrentes.

O protocolo aqui descrito permite a detecção de HSV-1 do genoma latente nos neurónios de secções de tecido neuronal de rato. O nosso conhecimento das vias que regulam a expressão de genes virais tem sido limitada pela falta de método para detectar ADN genómico de HSV-1 in situ no interior de tecidos neuronais. As informações sobre o número de cópias do genoma e proporção de neurônios infectados vieram principalmente de análise de PCR em neurônios dissociados 11,12. Em elucidar o pape...

<html> Vírus herpes simplex tipo 1 (HSV-1) é um vírus humano neurotrópico persistente, que estabelece uma infecção latente a longo prazo nos neurónios do gânglio trigeminal (TG) do sistema nervoso periférico, a partir do qual reactiva periodicamente para replicar e propagação. O HSV-1 é um genoma de 150 kb de dsDNA de localizações no núcleo do neurónio hospedeira, onde permanece como chromatinized plasmídeos multicópia, que não se integram no genoma da célula hospedeira de 1,2. Durante a latência, o programa genético de HSV-1 do ciclo replicativo é fortemente reprimida, e a expressão do gene é restringida ao transcrito associado à latência (TAL), locus de estabelecimento de latência para o início da reactivação 3. LAT produz um longo 8,5 kb não codificante RNA transformado em um grande 2 kb lariat estável, e vários miRNA 4-7. HSV-1 latência é assim caracterizado pela presença do ADN genómico virai, o ARN LAT, e a ausência de proteínas do ciclo replicativo detectáveis. ONTEÚDO &quot;&gt; Os modelos animais, predominantemente rato e coelho, são modelos experimentais recapitulando várias características de latência em humanos. Um dos principais interesses desses modelos é que eles permitem estudar aspectos fisiológicos do HSV-1 latência em hospedeiros imunocompetentes. Nas últimas décadas , muitas ferramentas experimentais, tais como vírus e ratinhos geneticamente modificados, foram desenvolvidos para estudar a fisiologia, genética e biologia celular do HSV-1 de latência, a partir de tecidos animais. Até agora, ADN genómico virai foi detectado e quantificado por mancha de Southern e qPCR de TGs dissociada. No entanto, não existe presentemente nenhum método disponível para a detecção de HSV-1 do genoma por hibridização in situ em secções de tecido 8. Consequentemente, a latência é rotineiramente avaliada em seções histológicas, através da detecção de LAT RNA por hibridação in situ de ARN em vez de A detecção do genoma viral. Porque não tem sido possível caracterizar as células infectadas com base na presença de genomas virais, this limitação técnica tem sido uma grande desvantagem para a análise de muitos aspectos das interacções hospedeiro-vírus, tais como a relação entre o genoma viral e a expressão de genes celulares e virais ou do hospedeiro mediadas por células de resposta imune 9,10. Mais importante ainda, a heterogeneidade da célula-a-célula da infecção latente permanece relativamente inexplorado e foi mostrado ser uma característica chave de latência em ratos e em neurónios sensoriais ganglionares humanos implantados em ratos SCID 11-17. Tipicamente, foi mostrado por qPCR que o genoma de HSV-1 Número de cópia por célula varia de 5 a várias centenas. Embora LAT aparece como um regulador chave da latência e reativação, os dados de qPCR em neurônios isolados e in situ PCR indicaram que apenas um subconjunto de neurônios latentes infectadas, tão baixo quanto 30%, expressa o locus LAT 11,12,18-21. Como a célula hospedeira e o ambiente celular no tecido impacto sobre o estabelecimento de latência do vírus ea expressão do gene viral permanece obscura. Descrevemos aqui um sólido fluorescente de hibridização in situ (FISH), o método para a detecção eficiente de baixa cópia de HSV-1 de ADN genómico dentro de secções de tecido de animais neuronais. Este método foi desenvolvido e utilizado por nós para obter acesso a resolução da microscopia de imagem de alta que é necessário estudar a interação do genoma viral com a célula hospedeira componentes intra-nucleares 22. Além disso, é descrito um método de coloração de múltiplos para a detecção simultânea do DNA viral com RNA e proteínas, o que é uma ferramenta única para descrever as interacções vírus-hospedeiro que regulam a expressão de genes virais. O método também pode ser aplicado a uma ampla gama de análises que requerem a detecção de HSV-1 do genoma latente, tais como a quantificação neurónios infectados em grande número de secções. Um passo fundamental é aplicar o tratamento de recuperação antigênica para fazer o DNA viral acessível a hibridização. Assim, este protocolo também pode ser eficiente para a detecçãode outros vírus dsDNA, que não são atualmente detectável por abordagens DNA-FISH convencionais dentro tecidos animais.

<table border="0" cellpadding="0" cellspacing="0" width="822">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="17">
			<td height="17" style="height:17px;width:203px;">Balb/c mice</td>
			<td style="width:189px;">Janvier, France</td>
			<td style="width:93px;"> </td>
			<td style="width:337px;">6 week-old females</td>
		</tr>
		<tr height="51">
			<td height="51" style="height:51px;">HSV-1 strains</td>
			<td>SC16 strain (wild type)</td>
			<td></td>
			<td style="width:337px;">See Labetoule, M. et al. (2003) Invest Ophthalmol Vis Sci 44: 217&#8211;225, for details on HSV-1 strain and virus stock preparation.</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Ketamine hydrochloride</td>
			<td>Sigma</td>
			<td>K2753</td>
			<td rowspan="2" style="width:337px;">Intraperitoneal injection of a solution containing Ketamine (100mg/kg) and Xylazine (10mg/kg)</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Xylazine hydrochloride</td>
			<td>Sigma</td>
			<td>X1251</td>
		</tr>
		<tr height="85">
			<td height="85" style="height:85px;">Paraformaldehyde (PFA)</td>
			<td>Sigma</td>
			<td>158127</td>
			<td style="width:337px;">Suspend 4g of PFA in 90mL of water. Add 50&#181;L of 1N NaOH, and heat at 60&#176;C in a water bath with agitation. PFA dissolves in about 30min. Add 10mL of 10X PBS. This solution can be prepared in advance and stored at -20 &#176;C in 5mL tubes. Caution. Manipulate under a fume hood.</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Physiological Saline</td>
			<td>Sigma</td>
			<td colspan="2">07982-100TAB-F</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">1X PBS, pH 7.4 (sterile)</td>
			<td>Life Technologies</td>
			<td>10010-015</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Sucrose</td>
			<td>Sigma</td>
			<td>84100</td>
			<td>Prepare a 20% sucrose solution in 1X PBS.</td>
		</tr>
		<tr height="51">
			<td height="51" style="height:51px;width:203px;">Cryosectionning embedding medium - Tissue-Tek OCT Compound -</td>
			<td>SAKURA</td>
			<td>4583</td>
			<td></td>
		</tr>
		<tr height="34">
			<td height="34" style="height:34px;">Large vector DNA purification kit</td>
			<td>Qiagen</td>
			<td>12462</td>
			<td style="width:337px;">To purify Cosmid or BAC vector containing HSV-1 genome and store at -20&#176;C</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Nick translation kit</td>
			<td>Roche Applied Sciences</td>
			<td>10 976 776 001</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Cy3-dCTP</td>
			<td>GE Healthcare</td>
			<td>PA53021</td>
			<td>Protect from light</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">0.5M EDTA</td>
			<td>Sigma</td>
			<td>E6758</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">G50 Mini spin column</td>
			<td>GE Healthcare</td>
			<td>27-5330-01 </td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Salmon sperm DNA 10mg/mL</td>
			<td>Invitrogen / Life Technologies</td>
			<td>15632-011</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Ethanol molecular biology grade</td>
			<td>Sigma</td>
			<td>87047</td>
			<td>Prepare a 70% solution</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Salmon sperm DNA</td>
			<td>Invitrogen / Life Technologies</td>
			<td>15632-011</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Formamid Molecular biology grade</td>
			<td>Sigma</td>
			<td>F9037</td>
			<td>Caution. Manipulate under fume hood.</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">HSV-1 biotinylated commercial probe </td>
			<td>Enzo Life Sciences</td>
			<td>ENZ-40838</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">ImmEdge hydrophobic pen</td>
			<td>Vector Laboratories</td>
			<td>H-4000</td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;">20X Saline Sodium Citrate (SSC)</td>
			<td>Sigma</td>
			<td>S6639</td>
			<td>Prepare a 2X SSC solution in ddH20.</td>
		</tr>
		<tr height="34">
			<td height="34" style="height:34px;">Triton X-100</td>
			<td>Sigma</td>
			<td>T8787</td>
			<td style="width:337px;">Prepare a 10% stock solution in water and store at +4&#176;C. Prepare the 0.5% solution in 1X PBS right before use.</td>
		</tr>
		<tr height="102">
			<td height="102" style="height:102px;">10mM sodium citrate pH 6.0</td>
			<td>Sigma</td>
			<td>S1804</td>
			<td style="width:337px;">Prepare a 100mM stock solution (10X). Weigh 10,5g of citric acid (MW 210.14. Caution, irritant and toxic, wear appropriate mask and gloves), and dissolve in 400mL water. Adjust pH at 6.0 with 1N NaOH (caution, irritant, wear gloves). Adjust to 500mL with distilled water. Dilute 10 times in distilled water before use.</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Acetic Acid</td>
			<td>Sigma</td>
			<td>320099</td>
			<td style="width:337px;"> </td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Methanol, molecular biology grade</td>
			<td>Sigma</td>
			<td>322415</td>
			<td style="width:337px;"> </td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Dextran sulfate - MW 500 000</td>
			<td>Euromedex</td>
			<td>EU0606-A</td>
			<td style="width:337px;"> </td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Denhardt&#39;s solution (100X)</td>
			<td>Euromedex</td>
			<td>1020-A</td>
			<td style="width:337px;"> </td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Rubber Cement &#34;FixoGum&#34;</td>
			<td>Marabut</td>
			<td>290110000</td>
			<td style="width:337px;"> </td>
		</tr>
		<tr height="34">
			<td height="34" style="height:34px;width:203px;">DNA purification kit - Qiaquick PCR purification kit -</td>
			<td>Qiagen</td>
			<td>28104</td>
			<td style="width:337px;"> </td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">T7 in vitro transcription kit</td>
			<td>Ambion / Life Technologies</td>
			<td>AM1314</td>
			<td style="width:337px;"> </td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Biotin-16-UTP</td>
			<td>Roche Applied Sciences</td>
			<td>11388908910</td>
			<td style="width:337px;"> </td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">RNA purification mini-column</td>
			<td>Qiagen</td>
			<td>73404</td>
			<td style="width:337px;"> </td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Ribonucleoside Vanadyl Complex</td>
			<td>New England Biolabs</td>
			<td>S1402S</td>
			<td style="width:337px;"> </td>
		</tr>
		<tr height="34">
			<td height="34" style="height:34px;">H2O2</td>
			<td>Sigma</td>
			<td>H3410</td>
			<td style="width:337px;">Prepare a 3% solution in distilled water. Store at +4 &#176;C and protect from light.</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Yeast tRNA</td>
			<td>Invitrogen</td>
			<td>15401011</td>
			<td style="width:337px;">prepare a 10mg/mL solution in RNAse free water</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Normal Goat Serum</td>
			<td>Invitrogen</td>
			<td>PCN5000</td>
			<td></td>
		</tr>
		<tr height="68">
			<td height="68" style="height:68px;">Primary antibodies</td>
			<td>Any supplier</td>
			<td></td>
			<td style="width:337px;">The following primary antibodies were used in the result section: anti-mouse CENP-A (rabbit mAb C51A7, Cell Signaling Technologies), and anti-ATRX H-300 (Santa Cruz Biotechnology)</td>
		</tr>
		<tr height="85">
			<td height="85" style="height:85px;">Secondary fluorescent antibodies</td>
			<td>Invitrogen / Life Technologies</td>
			<td></td>
			<td style="width:337px;">The fluorescent secondary antibodies routinely used in our protocol are AlexaFluor labeled goat antibodies (IgG H+L). The antibody used in the result section is an anti-rabbit goat antibody labaled with AlexaFluor 488 (reference A11001)</td>
		</tr>
		<tr height="51">
			<td height="51" style="height:51px;width:203px;">Tyramide Signal Amplification (TSA) kit - Streptavidin + AlexaFluor 350 (blue fluorescence)</td>
			<td>Invitrogen / Life Technologies</td>
			<td>#T20937</td>
			<td rowspan="2" style="width:337px;">TSA kits are also available from Perkin Elmer</td>
		</tr>
		<tr height="51">
			<td height="51" style="height:51px;width:203px;">Tyramide Signal Amplification (TSA) kit - Streptavidin + AlexaFluor 488 (green fluorescence)</td>
			<td>Invitrogen / Life Technologies</td>
			<td>#T20932</td>
		</tr>
		<tr height="34">
			<td height="34" style="height:34px;">Hoechst 33342</td>
			<td>Invitrogen / Life Technologies</td>
			<td>H3570</td>
			<td style="width:337px;">Prepare a 0.5&#181;g/mL solution in 1X PBS immediatly before use. Discard the remaining solution.</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">22x50mm coverslip. n&#176;1.5 glass.</td>
			<td>Electron Microscopy Sciences</td>
			<td>72204-04</td>
			<td style="width:337px;"> </td>
		</tr>
		<tr height="34">
			<td height="34" style="height:34px;width:203px;"> Mounting medium with anti-fading agent - Vectashield -</td>
			<td>Vector Laboratories</td>
			<td>H-1000</td>
			<td style="width:337px;">Another conventional product is Fluoromount G from electron microscopy Science</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Superfrost glass slides</td>
			<td>FisherScientific</td>
			<td>12-550-15</td>
			<td style="width:337px;"> </td>
		</tr>
		<tr height="18">
			<td height="18" style="height:18px;"> </td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">EQUIPMENT</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="18">
			<td height="18" style="height:18px;">Equipment / material</td>
			<td>Company</td>
			<td>Reference</td>
			<td>Note</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Needle for infection</td>
			<td></td>
			<td></td>
			<td>Glass micropipette hot drawn. Home made.</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Dissection equipement</td>
			<td>Moria, France</td>
			<td></td>
			<td>Microsurgical scissors and forceps</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Peristaltic pump</td>
			<td style="width:189px;">Cole Palmer Instruments</td>
			<td></td>
			<td>Easyload Masterflex</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Micro-syringe pump device (Nano Pump)</td>
			<td>kdScientific</td>
			<td>KDS310</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Cryostat</td>
			<td>Leica France</td>
			<td>CM 1510-1</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">-80 &#176;C freezer</td>
			<td>Sanyo</td>
			<td></td>
			<td>Ultra Low -80&#176;C</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Domestic microwave oven</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Dry block heater</td>
			<td>Eppendorf</td>
			<td>022670204</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Incubator Slide moat</td>
			<td>Boekel Scientific</td>
			<td>240000</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Coplin Jar</td>
			<td>Dominique Dutscher</td>
			<td>68512</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Staining glass container</td>
			<td>Dominique Dutscher</td>
			<td>68506</td>
			<td></td>
		</tr>
		<tr height="136">
			<td height="136" style="height:136px;">Fluorescent microscope</td>
			<td>Zeiss</td>
			<td></td>
			<td style="width:337px;">The images presented in the result section were collected with a Zeiss AxioObserver with objective x40 LD NeoFluor N.A 0.6, and x100 PlanApochromat N.A 1.3. Filter set #38, #43 and #43. HXP 120 fluorescence light source. Photometrics CoolSNAP HQ2 CCD camera. Signal will be more easily observed on a recent high efficiency microscope such as Zeiss AxioImager/AxioObserver series, Nikon Ti-E/Ni-E series or Leica DM/DMI6000 series</td>
		</tr>
	</tbody>
</table>

detection of the genome and transcripts of a persistent dna virus in neuronal tissues by fluorescent in situ hybridization combined with immunostaining

Codetection uma única célula de um gene, o seu produto de ARN e as proteínas reguladoras celulares é fundamental para o estudo da expressão gênica. Este é um grande desafio no campo da virologia e, em especial para os vírus de ADN persistentes-replicante nucleares que envolvem modelos animais para o estudo. Tipo de vírus Herpes simplex 1 (HSV-1) estabelece uma infecção latente ao longo da vida nos neurônios periféricos. Vírus latente serve como reservatório, a partir do qual reactiva e conduz a um novo episódio herpético. A biologia da célula de HSV-1 latência permanece mal compreendida, em parte devido à falta de métodos para detectar o HSV-1 genomas in situ em modelos animais. Descreve-se um DNA-hibridação in situ fluorescente (FISH) abordagem de detecção eficiente de baixa cópia genomas virais dentro das seções de tecidos neuronais a partir de modelos animais infectados. O método baseia-se à base de calor antigénio desmascaramento, e as sondas de ADN caseiros directamente marcados ou sondas disponíveis comercialmente. Desenvolvemos um stai triploabordagem ning, combinando DNA-FISH com RNA-FISH e imunofluorescência, utilizando peroxidase baseado amplificação de sinal para acomodar cada requisito de coloração. Uma grande melhoria é a possibilidade de obter, dentro de 10 um secções de tecido, os sinais de baixa de fundo que pode ser fotografada em alta resolução por microscopia confocal e de campo amplo epifluorescência convencional. Além disso, a coloração tripla trabalhou com uma ampla gama de anticorpos dirigidos contra as proteínas virais e celulares. O protocolo completo leva 2,5 dias para acomodar o anticorpo e a penetração da sonda no interior do tecido.

Depois de vários meses de testes extensos descobrimos que baseada em calor latente desmascaramento química feita de HSV-1 do genoma disponível para hibridização in situ fluorescente. Durante o processo, tentámos vários processos de desmascaramento, e tratamentos baseados apenas pelo calor (ou seja, o aquecimento das secções até à temperatura sub-ponto de ebulição em um forno de micro-ondas) apareceu eficiente. Em seguida, testamos vários buffers de sal que são rotineiramente utilizados e...

Watch this Scientific Journal Video about Detection of the Genome and Transcripts of a Persistent DNA Virus in Neuronal Tissues by Fluorescent In situ Hybridization Combined with Immunostaining at JoV

Detection of the Genome and Transcripts of a Persistent DNA Virus in Neuronal Tissues by Fluorescent In situ Hybridization Combined with Immunostaining

Foi estabelecido um protocolo de hibridização fluorescente in situ para a detecção de um genoma do vírus de ADN persistente nas secções de tecido de modelos animais. Este protocolo permite estudar processo de infecção por codetection do genoma viral, os seus produtos de ARN, e proteínas virais ou celulares no interior das células individuais.

A detecção do genoma e Transcrições de um vírus DNA persistente em tecidos neuronais por fluorescentes Em situ Hibridização Combinado com Imunocoloração

Single cell codetection of a gene, its RNA product and cellular regulatory proteins is critical to study gene expression regulation. This is a challenge ...

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Research

JoVE Journal

Neuroscience

Detection of the Genome and Transcripts of a Persistent DNA Virus in Neuronal Tissues by Fluorescent In situ Hybridization Combined with Immunostaining

18.2K visualizações.  CNRS UMR 5534.  Foi estabelecido um protocolo de hibridização fluorescente in situ para a detecção de um genoma do vírus de ADN persistente nas secções de tecido de modelos animais. Este protocolo permite estudar processo de infecção por codetection do genoma viral, os seus produtos de ARN, e proteínas virais ou celulares no interior das células individuais. 

Vídeo: Detection of the Genome and Transcripts of a Persistent DNA Virus in Neuronal Tissues by Fluorescent In situ Hybridization Combined with Immunostaining

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.

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.

Fluorescência dupla In situ Hibridação nas Seções cérebro fresco

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

Neurociência

Fast Micro-iontophoresis of Glutamate and GABA: A Useful Tool to Investigate Synaptic Integration

One of the fundamental interests in neuroscience is to understand the integration of excitatory and inhibitory inputs along the very complex structure of the dendritic tree, which eventually leads to neuronal output of action potentials at the axon. The influence of diverse spatial and temporal parameters of specific synaptic input on neuronal output is currently under investigation, e.g. the distance-dependent attenuation of dendritic inputs, the location-dependent interaction of spatially segregated inputs, the influence of GABAergig inhibition on excitatory integration, linear and non-linear integration modes, and many more.
With fast micro-iontophoresis of glutamate and GABA it is possible to precisely investigate the spatial and temporal integration of glutamatergic excitation and GABAergic inhibition. Critical technical requirements are either a triggered fluorescent lamp, light-emitting diode (LED), or a two-photon scanning microscope to visualize dendritic branches without introducing significant photo-damage of the tissue. Furthermore, it is very important to have a micro-iontophoresis amplifier that allows for fast capacitance compensation of high resistance pipettes. Another crucial point is that no transmitter is involuntarily released by the pipette during the experiment.
Once established, this technique will give reliable and reproducible signals with a high neurotransmitter and location specificity. Compared to glutamate and GABA uncaging, fast iontophoresis allows using both transmitters at the same time but at very distant locations without limitation to the field of view. There are also advantages compared to focal electrical stimulation of axons: with micro-iontophoresis the location of the input site is definitely known and it is sure that only the neurotransmitter of interest is released. However it has to be considered that with micro-iontophoresis only the postsynapse is activated and presynaptic aspects of neurotransmitter release are not resolved. In this article we demonstrate how to set up micro-iontophoresis in brain slice experiments.

In this article we introduce fast micro-iontophoresis of neurotransmitters as a technique to investigate integration of postsynaptic signals with high spatial and temporal precision.

Rápido Micro-iontoforese de glutamato e GABA: uma ferramenta útil para investigar Integração Synaptic

One of the fundamental interests in neuroscience is to understand the integration of excitatory and inhibitory inputs along the very complex structure of ...

Inducing Plasticity of Astrocytic Receptors by Manipulation of Neuronal Firing Rates

Close to two decades of research has established that astrocytes in situ and in vivo express numerous G protein-coupled receptors (GPCRs) that can be stimulated by neuronally-released transmitter. However, the ability of astrocytic receptors to exhibit plasticity in response to changes in neuronal activity has received little attention. Here we describe a model system that can be used to globally scale up or down astrocytic group I metabotropic glutamate receptors (mGluRs) in acute brain slices. Included are methods on how to prepare parasagittal hippocampal slices, construct chambers suitable for long-term slice incubation, bidirectionally manipulate neuronal action potential frequency, load astrocytes and astrocyte processes with fluorescent Ca2+ indicator, and measure changes in astrocytic Gq GPCR activity by recording spontaneous and evoked astrocyte Ca2+ events using confocal microscopy. In essence, a &#8220;calcium roadmap&#8221; is provided for how to measure plasticity of astrocytic Gq GPCRs. Applications of the technique for study of astrocytes are discussed. Having an understanding of how astrocytic receptor signaling is affected by changes in neuronal activity has important implications for both normal synaptic function as well as processes underlying neurological disorders and neurodegenerative disease.

Here we describe an adaptation of protocols used to induce homeostatic plasticity in neurons for the study of plasticity of astrocytic G protein-coupled receptors. Recently used to examine changes in astrocytic group I mGluRs in juvenile mice, the method can be applied to measure scaling of various astrocytic GPCRs, in tissue from adult mice in situ and in vivo, and to gain a better appreciation of the sensitivity of astrocytic receptors to changes in neuronal activity.

Induzir Plasticidade de astrocítica Receptores de Manipulação de Neuronal queima de moeda

Close to two decades of research has established that astrocytes in situ and in vivo express numerous G protein-coupled receptors (GPCRs) that can be ...

Intracerebroventricular Viral Injection of the Neonatal Mouse Brain for Persistent and Widespread Neuronal Transduction

With the pace of scientific advancement accelerating rapidly, new methods are needed for experimental neuroscience to quickly and easily manipulate gene expression in the mouse brain. Here we describe a technique first introduced by Passini and Wolfe for direct intracranial delivery of virally-encoded transgenes into the neonatal mouse brain. In its most basic form, the procedure requires only an ice bucket and a microliter syringe. However, the protocol can also be adapted for use with stereotaxic frames to improve consistency for researchers new to the technique. The method relies on the ability of adeno-associated virus (AAV) to move freely from the cerebral ventricles into the brain parenchyma while the ependymal lining is still immature during the first 12-24 hr after birth. Intraventricular injection of AAV at this age results in widespread transduction of neurons throughout the brain. Expression begins within days of injection and persists for the lifetime of the animal. Viral titer can be adjusted to control the density of transduced neurons, while co-expression of a fluorescent protein provides a vital label of transduced cells. With the rising availability of viral core facilities to provide both off-the-shelf, pre-packaged reagents and custom viral preparation, this approach offers a timely method for manipulating gene expression in the mouse brain that is fast, easy, and far less expensive than traditional germline engineering.

Here we demonstrate a technique for widespread neuronal transduction by intraventricular injection of adeno-associated virus into the neonatal mouse brain. This method provides a rapid and easy way to attain lifelong expression of virally-delivered transgenes.

Injection Viral intracerebroventricular do Neonatal do rato do cérebro para a transdução neuronal persistente e generalizada

With the pace of scientific advancement accelerating rapidly, new methods are needed for experimental neuroscience to quickly and easily manipulate gene ...

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.

Detecção de Axonally localizada mRNAs em seções do cérebro Usando de alta resolução<em&gt; In Situ</em&gt; Hibridização

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

Utilizing Combined Methodologies to Define the Role of Plasma Membrane Delivery During Axon Branching and Neuronal Morphogenesis

During neural development, growing axons extend to multiple synaptic partners by elaborating axonal branches. Axon branching is promoted by extracellular guidance cues like netrin-1 and results in dramatic increases to the surface area of the axonal plasma membrane. Netrin-1-dependent axon branching likely involves temporal and spatial control of plasma membrane expansion, the components of which are supplied through exocytic vesicle fusion. These fusion events are preceded by formation of SNARE complexes, comprising a v-SNARE, such as VAMP2 (vesicle-associated membrane protein 2), and plasma membrane t-SNAREs, syntaxin-1 and SNAP25 (synaptosomal-associated protein 25). Detailed herein isa multi-pronged approach used to examine the role of SNARE mediated exocytosis in axon branching. The strength of the combined approach is data acquisition at a range of spatial and temporal resolutions, spanning from the dynamics of single vesicle fusion events in individual neurons to SNARE complex formation and axon branching in populations of cultured neurons. This protocol takes advantage of established biochemical approaches to assay levels of endogenous SNARE complexes and Total Internal Reflection Fluorescence (TIRF) microscopy of cortical neurons expressing VAMP2 tagged with a pH-sensitive GFP (VAMP2-pHlourin) to identify netrin-1 dependent changes in exocytic activity in individual neurons. To elucidate the timing of netrin-1-dependent branching, time-lapse differential interference contrast (DIC) microscopy of single neurons over the order of hours is utilized. Fixed cell immunofluorescence paired with botulinum neurotoxins that cleave SNARE machinery and block exocytosis demonstrates that netrin-1 dependent axon branching requires SNARE-mediated exocytic activity.

Light microscopy techniques coupled with biochemical assays elucidate the involvement of SNARE-mediated exocytosis in netrin-dependent axon branching. This combination of techniques permits identification of molecular mechanisms controlling axon branching and cell shape change.

Utilizando metodologias combinadas para definir o papel do Plasma Membrane entrega durante Axon Ramificação e Neuronal morfogênese

During neural development, growing axons extend to multiple synaptic partners by elaborating axonal branches. Axon branching is promoted by extracellular ...

Extracellular Recording of Neuronal Activity Combined with Microiontophoretic Application of Neuroactive Substances in Awake Mice

Differences in the activity of neurotransmitters and neuromodulators, and consequently different neural responses, can be found between anesthetized and awake animals. Therefore, methods allowing the manipulation of synaptic systems in awake animals are required in order to determine the contribution of synaptic inputs to neuronal processing unaffected by anesthetics. Here, we present methodology for the construction of electrodes to simultaneously record extracellular neural activity and release multiple neuroactive substances at the vicinity of the recording sites in awake mice. By combining these procedures, we performed microiontophoretic injections of gabazine to selectively block GABAA receptors in neurons of the inferior colliculus of head-restrained mice. Gabazine successfully modified neural response properties such as the frequency response area and stimulus-specific adaptation. Thus, we demonstrate that our methods are suitable for recording single-unit activity and for dissecting the role of specific neurotransmitter receptors in auditory processing.
The main limitation of the described procedure is the relatively short recording time (~3 hr), which is determined by the level of habituation of the animal to the recording sessions. On the other hand, multiple recording sessions can be performed in the same animal. The advantage of this technique over other experimental procedures used to manipulate the level of neurotransmission or neuromodulation (such as systemic injections or the use of optogenetic models), is that the drug effect is confined to the local synaptic inputs to the target neuron. In addition, the custom-manufacture of electrodes allows adjustment of specific parameters according to the neural structure and type of neuron of interest (such as the tip resistance for improving the signal-to-noise ratio of the recordings).

We present methods for the construction of electrodes to simultaneously record extracellular neural activity and release multiple neuroactive substances at the vicinity of the recording sites in awake mice. This technique allows the detailed analysis of putative local synaptic inputs to the neuron of interest.

Extracelular Gravação de Neuronal Atividade Combinado com Microiontophoretic aplicação de substâncias neuroativos em Ratos Awake

Differences in the activity of neurotransmitters and neuromodulators, and consequently different neural responses, can be found between anesthetized and ...

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.

Combinando Duplo Fluorescência<em&gt; In Situ</em&gt; A hibridação com imunomarcação para a detecção da expressão de três genes em secções do cérebro do rato

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.

Localização de Genes de Receptor de Odorantes em Antenas de Locustídeo por RNA<em&gt; In Situ</em&gt; Hibridação

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

Identification of Dopamine D1-Alpha Receptor Within Rodent Nucleus Accumbens by an Innovative RNA In Situ Detection Technology

In the central nervous system, the D1-alpha subtype receptor (Drd1&#945;) is the most abundant dopamine (DA) receptor, which plays a vital role in regulating neuronal growth and development. However, the mechanisms underlying Drd1&#945; receptor abnormalities mediating behavioral responses and modulating working memory function are still unclear. Using a novel RNA in situ hybridization assay, the current study identified dopamine Drd1&#945; receptor and tyrosine hydroxylase (TH) RNA expression from DA-related circuitry in the nucleus accumbens (NAc) area and substantia nigra region (SNR), respectively. Drd1&#945; expression in the NAc shows a &#34;discrete dot&#34; staining pattern. Clear sex differences in Drd1&#945; expression were observed. In contrast, TH shows a &#34;clustered&#34; staining pattern. Regarding TH expression, female rats displayed a higher signal expression per cell relative to male animals. The methods presented here provide a novel in situ hybridization technique for investigating changes in dopamine system dysfunction during the progression of central nervous system diseases.

Identification of Dopamine D1-Alpha Receptor Within Rodent Nucleus Accumbens by an Innovative RNA In Situ Detection Technology

Identification of dopamine D1-alpha receptor in the nucleus accumbens is critical for clarifying D1 receptor dysfunction during a central nervous system disease. We performed a novel RNA in situ hybridization assay to visualize single RNA molecules in a specific brain area.