Los autores desean agradecer a todos los miembros de Jarvis de laboratorio que mejoraron el protocolo a través de los años.

<ol>
	<li>Clayton, D. F., Huecas, M. E., Sinclair-Thompson, E. Y., Nastiuk, K. L., Nottebohm, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Probes+for+rare+mRNAs+reveal+distributed+cell+subsets+in+canary+brain.">Probes for rare mRNAs reveal distributed cell subsets in canary brain.</a> Neuron. 1, 249-261 (1988).</li><li>Wada, K., Sakaguchi, H., Jarvis, E. D., Hagiwara, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+expression+of+glutamate+receptors+in+avian+neural+pathways+for+learned+vocalization.">Differential expression of glutamate receptors in avian neural pathways for learned vocalization.</a> J. Comp. Neurol. 476, 44-64 (2004).</li><li>Haesler, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=FoxP2+expression+in+avian+vocal+learners+and+non-learners.">FoxP2 expression in avian vocal learners and non-learners.</a> J. Neurosci. 24, 3164-3175 (2004).</li><li>Jarvis, E. D., Nottebohm, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Motor-driven+gene+expression.">Motor-driven gene expression.</a> Proc. Natl. Acad. Sci. U.S.A. 94, 4097-4102 (1997).</li><li>Holzenberger, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+expression+of+insulin-like+growth+factor+II+in+the+songbird+brain.">Selective expression of insulin-like growth factor II in the songbird brain.</a> J. Neurosci. 17, 6974-6987 (1997).</li><li>Mahmood, R., Mason, I. <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+of+radioactive+riboprobes+to+RNA+in+tissue+sections.">In-situ hybridization of radioactive riboprobes to RNA in tissue sections.</a> Methods Mol. Biol. 461, 675-686 (2008).</li><li>Wilkinson, D. G., Nieto, M. 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+messenger+RNA+by+in+situ+hybridization+to+tissue+sections+and+whole+mounts.">Detection of messenger RNA by in situ hybridization to tissue sections and whole mounts.</a> Methods Enzymol. 225, 361-373 (1993).</li><li>Acloque, H., Wilkinson, D. G., Nieto, M. 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+situ+hybridization+analysis+of+chick+embryos+in+whole-mount+and+tissue+sections.">In situ hybridization analysis of chick embryos in whole-mount and tissue sections.</a> Methods Cell Biol. 87, 169-185 (2008).</li><li>Moorman, A. F., Houweling, A. C., de Boer, P. A., Christoffels, V. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sensitive+nonradioactive+detection+of+mRNA+in+tissue+sections:+novel+application+of+the+whole-mount+in+situ+hybridization+protocol.">Sensitive nonradioactive detection of mRNA in tissue sections: novel application of the whole-mount in situ hybridization protocol.</a> J. Histochem. Cytochem. 49, 1-8 (2001).</li><li>Horita, H., Wada, K., Rivas, M. V., Hara, E., Jarvis, E. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+dusp1+immediate+early+gene+is+regulated+by+natural+stimuli+predominantly+in+sensory+input+neurons.">The dusp1 immediate early gene is regulated by natural stimuli predominantly in sensory input neurons.</a> J. Comp. Neurol. 518, 2873-2901 (2010).</li><li>Braissant, O., Wahli, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+simplified+in+situ+hybridization+protocol+using+non-radioactively+labelled+probes+to+detect+abundant+and+rare+mRNAs+on+tissue+sections.">A simplified in situ hybridization protocol using non-radioactively labelled probes to detect abundant and rare mRNAs on tissue sections.</a> Biochemica. 1, 10-16 (1998).</li><li>Kubikova, L., Wada, K., Jarvis, E. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dopamine+receptors+in+a+songbird+brain.">Dopamine receptors in a songbird brain.</a> J. Comp. Neurol. 518, 741-769 (2010).</li><li>Wada, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+molecular+neuroethological+approach+for+identifying+and+characterizing+a+cascade+of+behaviorally+regulated+genes.">A molecular neuroethological approach for identifying and characterizing a cascade of behaviorally regulated genes.</a> Proc. Natl. Acad. Sci. U.S.A. 103, 15212-15217 (2006).</li><li>Jarvis, E. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Avian+brains+and+a+new+understanding+of+vertebrate+brain+evolution.">Avian brains and a new understanding of vertebrate brain evolution.</a> Nat. Rev. Neurosci. 6, 151-159 (2005).</li><li>Hoke, K. L., Ryan, M. J., Wilczynski, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Social+cues+shift+functional+connectivity+in+the+hypothalamus.">Social cues shift functional connectivity in the hypothalamus.</a> Proc. Natl. Acad. Sci. U.S.A. 102, 10712-10717 (2005).</li><li>Burmeister, S. S., Jarvis, E. D., Fernald, R. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+behavioral+and+genomic+responses+to+social+opportunity.">Rapid behavioral and genomic responses to social opportunity.</a> PLoS. Biol. 3, e363 (2005).</li><li>Jarvis, E. D., Schwabl, H., Ribeiro, S., 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=Brain+gene+regulation+by+territorial+singing+behavior+in+freely+ranging+songbirds.">Brain gene regulation by territorial singing behavior in freely ranging songbirds.</a> Neuroreport. 8, 2073-2077 (1997).</li><li>Jarvis, E. D., Scharff, C., Grossman, M. R., Ramos, J. A., Nottebohm, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=For+whom+the+bird+sings:+context-dependent+gene+expression.">For whom the bird sings: context-dependent gene expression.</a> Neuron. 21, 775-788 (1998).</li><li>Feenders, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+mapping+of+movement-associated+areas+in+the+avian+brain:+a+motor+theory+for+vocal+learning+origin.">Molecular mapping of movement-associated areas in the avian brain: a motor theory for vocal learning origin.</a> PLoS One. 3, e1768 (2008).</li><li>Chen, C. C., Fernald, R. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distributions+of+two+gonadotropin-releasing+hormone+receptor+types+in+a+cichlid+fish+suggest+functional+specialization.">Distributions of two gonadotropin-releasing hormone receptor types in a cichlid fish suggest functional specialization.</a> J. Comp. Neurol. 495, 314-323 (2006).</li></ol>

No tenemos nada que revelar.

Radiactivos hibridación in situ de la expresión del ARNm es ampliamente utilizado para múltiples propósitos, incluyendo para el estudio de la organización del tejido regional, tipos de células, y la actividad funcional del cerebro 2-5,10,12-14. El uso posterior está en los genes cuya expresión de ARNm en el cerebro depende de una mayor actividad neuronal, a menudo llamados los genes dependientes de la actividad o de genes tempranos inmediatos. Con esta finalidad, nuestro método ha sido aplicado a través de múltiples especies, en particular en las aves, los mamíferos (humanos), los peces y los anfibios; en varios tejidos, incluyendo cerebro, piel y músculo, y de edades múltiples, incluyendo los neonatos o recién nacidos, menores de edad , los adultos, y aquí, en secciones de embriones enteros 2,3,5,15-17. Las características especiales de nuestro protocolo incluyen: (1) Se produce un equilibrio entre la especificidad anatómica y la especificidad cuantitativa. Para cuantificar la expresión génica en la película de rayos X, tomamos fotografías digitales de las imágenes (por ejemplo:. Fig. 1A y 1B), utilice el Photoshop (Adobe) la función de histograma para medir la densidad de píxeles en las regiones de interés y restar los niveles de fondo de la película fuera de los tejidos, pero todavía en el portaobjetos de vidrio 2,4. Para cuantificar la expresión a nivel celular, tomamos las imágenes de los granos de plata sobre las células con gran aumento (40-100X, Fig. 4). A continuación, utilizamos el umbral y las funciones de medida de la J de la imagen de Wayne Rasband en los NIH para contar el número de granos de plata en la imagen, se resta el recuento de fondo en un área similar sin células de la lámina de vidrio, se divide por el número de células, para obtener valores de expresión por célula. 4,18 (2) Se puede medirse el flujo relativamente alta, permitiendo el procesamiento de 100-200 diapositivas simultáneamente, debido a la junta de cubreobjetos apretado creado por el baño de aceite mineral. Standard in situ los métodos de hibridación tomar más tiempo para sellar los portaobjetos con parafina, esmalte de uñas, y otros medios, donde las diapositivas ocupan mucho espacio, (3) Es muysensible para transcripciones de baja abundancia debido a sulfato de dextrano y solución de Denhardt en el tampón de hibridación 2,13; (4) El enfoque de imágenes en campo oscuro produce imágenes de alto contraste, debido a la toma de fotografías bajo iluminación en campo oscuro en un microscopio de disección 4,5. Además, permite la detección sensible de los pequeños cambios en la expresión génica, tales como en la expresión génica dependiente de la actividad para identificar regiones específicas del cerebro activadas durante la percepción y la producción de comportamientos específicos 19. Las limitaciones relativas a no radiactivos protocolos son que los últimos son más clara en la resolución celular y la localización del ARNm dentro de la célula, y trabajando con emulsión es muy sensible a la manipulación y la luz. Es posible combinar nuestro método con otros métodos, tales como no radiactivos en hibridación in situ para etiquetar la expresión del ARNm de más de un gen en el mismo tejido 10,17,20. Se puede combinar con inmunocitoquímicapara etiquetar ambos ARN y la expresión de proteínas en la misma muestra con el fin de co-localizar el ARNm con ciertos tipos de células 10. Las modificaciones de protocolo necesarios para tales experimentos de marcaje doble se describen en las referencias citadas. En resumen, nuestro enfoque facilita la comprensión del momento y la localización celular de la expresión génica con el fin de entender la organización la región, la actividad del tejido funcional, y la función del gen.

<table border="1"><tbody><tr><td> Nombre del reactivo </td><td> Empresa </td><td> Número de catálogo </td><td> Comentarios </td></tr><tr><td> El anhídrido acético </td><td> VWR </td><td> MK242002 </td><td></td></tr><tr><td> Cloroformo </td><td> VWR </td><td> BDH1109 </td><td></td></tr><tr><td> Acetato de violeta de cresilo </td><td> Sigma </td><td> C5042 </td><td></td></tr><tr><td> Criostato </td><td> Thermo Scientific </td><td> Microm HM550 </td><td></td></tr><tr><td> Formamida desionizada </td><td> Sigma </td><td> F9037 </td><td></td></tr><tr><td> TDT </td><td> Promega </td><td> P1171 </td><td> 100 mM </td></tr><tr><td> EDTA </td><td> Sigma </td><td> ED </td><td></td></tr><tr><td> Incrustación de molde </td><td> VWR </td><td> 15160-215 </td><td></td></tr><tr><td> Fisher marca Superfrost Plus diapositivas </td><td> Fisher Scientific </td><td> 22-034-979 </td&gt; <td></td></tr><tr><td> Formaldehído </td><td> VWR </td><td> BDH0506-4LP </td><td></td></tr><tr><td> Formamida </td><td> Sigma </td><td> F7508 </td><td></td></tr><tr><td> GENECLEAN kit </td><td> Q-Bio gen </td><td> 1001-200 </td><td></td></tr><tr><td> Kodak Biomax MR película </td><td> Sigma </td><td> Z350370 </td><td></td></tr><tr><td> Kodak NTB Emulsión </td><td> Carestream Health </td><td> 8895666 </td><td></td></tr><tr><td> Kodak Professional Developer D19 </td><td> Kodak </td><td> 1462593 </td><td></td></tr><tr><td> Kodak Professional Fixer </td><td> Kodak </td><td> 1971746 </td><td></td></tr><tr><td> β-mercaptoetanol </td><td> Calbiochem </td><td> 444203 </td><td></td></tr><tr><td> Aceite mineral </td><td> VWR </td><td> IC15169491 </td><td></td></tr><tr><td> NaOH </td><td> VWR </td><td> SX0600-1 </td><td></td></tr><tr><td> Paraformaldehído </td><td> Sigma </td><td> 76240 </td><td></td></tr><tr><td> Poli A </td><td> Invitrogen </td><td> POLYA.GF </td><td></td></tr><tr><td> rATP </td><td> Promega </td><td> P1132 </td><td> 10 mM </td></tr><tr><td> rCTP </td><td> Promega </td><td> P1142 </td><td> 10 mM </td></tr><tr><td> rGTP </td><td> Promega </td><td> P1152 </td><td> 10 mM </td></tr><tr><td> RNasin </td><td> Promega </td><td> N2111 </td><td> 40Units/μl </td></tr><tr><td> S 35 UTP </td><td> PerkinElmer </td><td> NEG039C001MC </td><td></td></tr><tr><td> Seguridad-Solve solución </td><td> Resolver Investigación de Productos de Seguridad Internacional </td><td> 111177 </td><td></td></tr><tr><td> Acetato de sodio </td><td> Sigma </td><td> S7899 </td><td> 3M </td></tr><tr><td> Fosfato sódico dibásico </td><td> Sigma </td><td> S3264 </td><td></td></tr><tr><td> Fosfato sódico monobásico </td><td> Sigma </td><td> S3139 </td><td></td></tr><tr><td> SP6ARN polimerasa </td><td> Promega </td><td> P1085 </td><td></td></tr><tr><td> La tinción parrilla de metal </td><td> Microscopía Electrónica de Ciencias </td><td> 70312-54 </td><td></td></tr><tr><td> T7 ARN polimerasa </td><td> Promega </td><td> P2075 </td><td></td></tr><tr><td> Tissue-Tek octubre </td><td> Sakura </td><td> 4583 </td><td></td></tr><tr><td> Transcripción tampón 5x </td><td> Promega </td><td> P1181 </td><td></td></tr><tr><td> Trietanolamina </td><td> VWR </td><td> IC15216391 </td><td></td></tr><tr><td> Tris-HCl (1 M, pH 8,0) </td><td> VWR </td><td> 101449-446 </td><td></td></tr><tr><td> tRNA </td><td> Roche </td><td> 10109509001 </td><td></td></tr></tbody></table> Soluciones: <ol><li> Reactivos para la fabricación de riboprobes: 1,5 l de ADN plantilla (0,2-0,3 g / l), 2 l de tampón 5x transcripción optimizado, 1 l de DTT 100 mM (viene con la polimerasa de Promega, la mezcla depocillo a temperatura ambiente), 0,3 l de RNasin (40 unidades / l), 1,5 l de solución de AGC mezcla ribonucleótido, 3,5 l de S 35 UTP, y 1 l ARN polimerasa. Lleve hasta 10 ml con agua libre de nucleasa. </li><li> Ribonucleótido AGC mezcla de solución: mezclar cantidades iguales de 10 mM de ATP, GTP y CTP juntos. </li><li> Solución de acetato de sodio para EtOH precipitación para eliminar 35 S libre UTP: 40 l RNasa y DNasa agua libre, 5 l de acetato sódico 3M, y 125 l de EtOH al 100%. </li><li> Hibridación tampón (10 ml stock): 5 ml de 100% de formamida desionizada, 600 l de NaCl 5M, 1M Tris-HCl (pH = 8,0), 240 l de EDTA 0,5 M (pH = 8,0), 100 l de solución de Denhart 100x, 100 l de 1M TDT, 250 l de 20mg/ml ARNt, 125 l de 20 mg / ml de poli A, y 1 g de sodio sulfato de dextrano. Añadir agua tratada con DEPC para llevar el volumen total a 10 ml. Agitar vigorosamente y luego se incuba a 55 ° C hasta que todo el sulfato de dextrano sódico se disuelve. Almacenar el tampón de hibridación en el-20 ° C, lo que es bueno para ~ 6 meses. </li><li> 4% tamponada solución de paraformaldehído: Añadir 40 g de paraformaldehido en 760 ml de agua destilada en un matraz designado para paraformaldehído, el calor a 50 ° C sobre una placa caliente mientras se agita. Añadir 320 l de NaOH 10N para ayudar a disolver el paraformaldehido. Después de la disolución (~ 10 minutos), añadir 100 ml de PBS 10x, y llevar el volumen con agua destilada hasta 1 litro. Agitar y calentar la solución hasta que se disuelve paraformaldehído. El pH debe ser 7,4. </li><li> La acetilación tampón: 13,6 ml de trietanolamina además 2,52 ml de anhídrido acético en 1 litro de agua destilada. </li><li> 20x SSPE solución: 3M NaCl, 200 mM NaH 2 PO 4-H 2 O, y 200 mM EDTA en agua destilada. Ajuste solución a pH 7,4 con NaOH 10N. </li><li> 10x tampón PBS: 80 g de NaCl, 2,0 g de KCl, 14,4 g de Na 2 HPO 4, y 2,4 g de KH 2 PO 4 en agua destilada. Ajuste solución a pH 7,0 y llevar el volumen total a 1 Liter. </li><li> Segunda solución de lavado: 0,1% β-mercaptoetanol y 50% de formamida en 2x SSPE </li><li> Violeta de cresilo solución de acetato: 3% de acetato de violeta de cresilo en agua del grifo (agua destilada evita buena tinción), se disolvió durante la noche con agitación en un matraz a temperatura ambiente. Filtrar por succión de vacío a través de un papel de filtro Whatman 1 mm y un embudo de Buchner. </li></ol>

radioactive in situ hybridization for detecting diverse gene expression patterns in tissue

Conociendo el tiempo, nivel, localización celular, y el tipo de células que un gen se expresa en contribuye a la comprensión de la función del gen. Cada una de estas características se puede lograr con la hibridación in situ a ARNm en las células. Aquí les presentamos una radiactivo en el método de hibridación in situ modificado a partir de Clayton et al. (1988) 1, que ha estado trabajando con éxito en nuestro laboratorio desde hace muchos años, especialmente para los adultos cerebro de un vertebrado 2-5. Los largos ARN complementario (cRNA) sondas a la secuencia diana permite la detección de las transcripciones de baja abundancia 6,7. La incorporación de nucleótidos radiactivos en las sondas cRNA permite la sensibilidad de detección adicional de las transcripciones de baja abundancia y análisis cuantitativos, ya sea por la luz sensible película de rayos X o emulsión revestido sobre el tejido. Estos métodos de detección de proporcionar un registro a largo plazo de un gen determinado. En comparación con los no radiactivo de la sonda de metanfetaminamétodos, como DIG-etiquetado, el método de sonda de hibridación radiactiva no requiere de varios pasos de amplificación utilizando HRP-anticuerpos y / o kit de la TSA para detectar la transcripción de baja abundancia. Por lo tanto, este método proporciona una relación lineal entre la intensidad de señal y las cantidades específicas de mRNA para el análisis cuantitativo. Se permite el tratamiento 100-200 diapositivas simultáneamente. Funciona bien para diferentes etapas de desarrollo de los embriones. Mayoría de los estudios de desarrollo de la expresión génica utilizar embriones enteros y los enfoques no radiactivos 8,9, en parte porque el tejido embrionario es más frágil que el tejido adulto, con una menor cohesión entre las células, lo que hace difícil ver los límites entre las poblaciones de células con las secciones de tejido. En contraste, el enfoque radiactivos, debido a la mayor gama de sensibilidad, es capaz de obtener un mayor contraste en la resolución de la expresión génica entre las regiones de tejido, por lo que es más fácil de ver los límites entre las poblaciones. El uso de este método, los investigadores podrían revelar laposible significado de un gen recién identificado, y además predecir la función del gen de interés.

Watch this Scientific Journal Video about Radioactive in situ Hybridization for Detecting Diverse Gene Expression Patterns in Tissue at JoVE.com

Radioactive in situ Hybridization for Detecting Diverse Gene Expression Patterns in Tissue

Este protocolo se utiliza con éxito para detectar cuantitativamente los niveles y los patrones espaciales de la expresión del ARNm de múltiples tipos de tejidos a través de las especies de vertebrados. El método puede detectar transcripciones baja abundancia y permite el tratamiento de cientos de diapositivas simultáneamente. Se presenta el protocolo de uso de perfiles de expresión de la formación del cerebro del embrión aviar como ejemplo.

Radioactivo In situ La hibridación para la detección de diversos patrones de expresión génica en el tejido

Knowing the timing, level, cellular localization, and cell type that a gene is expressed in contributes to our understanding of the function of the gene. ...

radioactive-situ-hybridization-for-detecting-diverse-gene-expression

Research

JoVE Journal

Biology

Radioactive in situ Hybridization for Detecting Diverse Gene Expression Patterns in Tissue

15.5K vistas.  Duke University. Este protocolo se utiliza con éxito para detectar cuantitativamente los niveles y los patrones espaciales de la expresión del ARNm de múltiples tipos de tejidos a través de las especies de vertebrados. El método puede detectar transcripciones baja abundancia y permite el tratamiento de cientos de diapositivas simultáneamente. Se presenta el protocolo de uso de perfiles de expresión de la formación del cerebro del embrión aviar como ejemplo.

Video: Radioactive in situ Hybridization for Detecting Diverse Gene Expression Patterns in Tissue

The Preparation of Primary Hematopoietic Cell Cultures From Murine Bone Marrow for Electroporation

It is becoming increasingly apparent that electroporation is the most effective way to introduce plasmid DNA or siRNA into primary cells. The Gene Pulser MXcell  electroporation system and Gene Pulser  electroporation buffer were specifically developed to transfect nucleic acids into mammalian cells and difficult-to-transfect cells, such as primary and stem cells.This video demonstrates how to establish primary hematopoietic cell cultures from murine bone marrow, and then prepare them for electroporation in the MXcell system. We begin by isolating femur and tibia. Bone marrow from both femur and tibia are then harvested and cultures are established. Cultured bone marrow cells are then transfected and analyzed.

This procedure describes how to establish primary hematopoietic cell cultures from murine bone marrow and is followed by transfection using the Gene Pulser MXCell electroporation system.

La preparación de cultivos primarios de células hematopoyéticas de la médula ósea murina por electroporación

It is becoming increasingly apparent that electroporation is the most effective way to introduce plasmid DNA or siRNA into primary cells. The Gene Pulser ...

Investigación

Biología

Non-radioactive in situ Hybridization Protocol Applicable for Norway Spruce and a Range of Plant Species

The high-throughput expression analysis technologies available today give scientists an overflow of expression profiles but their resolution in terms of tissue specific expression is limited because of problems in dissecting individual tissues. Expression data needs to be confirmed and complemented with expression patterns using e.g. in situ hybridization, a technique used to localize cell specific mRNA expression. The in situ hybridization method is laborious, time-consuming and often requires extensive optimization depending on species and tissue. In situ experiments are relatively more difficult to perform in woody species such as the conifer Norway spruce (Picea abies). Here we present a modified DIG in situ hybridization protocol, which is fast and applicable on a wide range of plant species including P. abies. With just a few adjustments, including altered RNase treatment and proteinase K concentration, we could use the protocol to study tissue specific expression of homologous genes in male reproductive organs of one gymnosperm and two angiosperm species; P. abies, Arabidopsis thaliana and Brassica napus. The protocol worked equally well for the species and genes studied. AtAP3 and BnAP3 were observed in second and third whorl floral organs in A. thaliana and B. napus and DAL13 in microsporophylls of male cones from P. abies. For P. abies the proteinase K concentration, used to permeablize the tissues, had to be increased to 3 g/ml instead of 1 g/ml, possibly due to more compact tissues and higher levels of phenolics and polysaccharides. For all species the RNase treatment was removed due to reduced signal strength without a corresponding increase in specificity. By comparing tissue specific expression patterns of homologous genes from both flowering plants and a coniferous tree we demonstrate that the DIG in situ protocol presented here, with only minute adjustments, can be applied to a wide range of plant species. Hence, the protocol avoids both extensive species specific optimization and the laborious use of radioactively labeled probes in favor of DIG labeled probes. We have chosen to illustrate the technically demanding steps of the protocol in our film.
Anna Karlgren and Jenny Carlsson contributed equally to this study.
Corresponding authors: Anna Karlgren at Anna.Karlgren@ebc.uu.se and Jens F. Sundstr&#246;m at Jens.Sundstrom@vbsg.slu.se

Non-radioactive in situ Hybridization Protocol Applicable for Norway Spruce and a Range of Plant Species

We describe a modified DIG in situ hybridization protocol, which is fast and applicable on a wide range of plant species including Norway spruce. With just a few adjustments, including altered RNase treatment and proteinase K concentration, the protocol may be used in studies of different tissues and species.

No radiactivo In situ La hibridación aplicable para el abeto rojo protocolo y una serie de especies de plantas

The high-throughput expression analysis technologies available today give scientists an overflow of expression profiles but their resolution in terms of ...

Using the Gene Pulser MXcell Electroporation System to Transfect Primary Cells with High Efficiency

It is becoming increasingly apparent that electroporation is the most effective way to introduce plasmid DNA or siRNA into primary cells. The Gene Pulser MXcell electroporation system and Gene Pulser electroporation buffer (Bio-Rad) were specifically developed to easily transfect nucleic acids into mammalian cells and difficult-to-transfect cells, such as primary and stem cells. We will demonstrate how to perform a simple experiment to quickly identify the best electroporation conditions. We will demonstrate how to run several samples through a range of electroporation conditions so that an experiment can be conducted at the same time as optimization is performed. We will also show how optimal conditions identified using 96-well electroporation plates can be used with standard electroporation cuvettes, facilitating the switch from electroporation plates to electroporation cuvettes while maintaining the same electroporation efficiency. In the video, we will also discuss some of the key factors that can lead to the success or failure of electroporation experiments.

This procedure shows how to use the Gene Pulser MXcell electroporation system to rapidly and easily identify the best electroporation conditions for mouse embryonic fibroblasts (MEFs) or other primary cells. Considerations for troubleshooting are also discussed in the associated video.

Utilizando el sistema de electroporación Gene Emisores MXcell para transfectar células primarias con alta eficiencia

Using an Automated Cell Counter to Simplify Gene Expression Studies: siRNA Knockdown of IL-4 Dependent Gene Expression in Namalwa Cells

The use of siRNA mediated gene knockdown is continuing to be an important tool in studies of gene expression.  siRNA studies are being conducted not only to study the effects of downregulating single genes, but also to interrogate signaling pathways and other complex interaction networks.  These pathway analyses require both the use of relevant cellular models and methods that cause less perturbation to the cellular physiology.  Electroporation is increasingly being used as an effective way to introduce siRNA and other nucleic acids into difficult to transfect cell lines and primary cells without altering the signaling pathway under investigation. There are multiple critical steps to a successful siRNA experiment, and there are ways to simplify the work while improving the data quality at several experimental stages.  To help you get started with your siRNA mediated gene knockdown project, we will demonstrate how to perform a pathway study complete from collecting and counting the cells prior to electroporation through post transfection real-time PCR gene expression analysis.  The following study investigates the role of the transcriptional activator STAT6 in IL-4 dependent gene expression of CCL17 in a Burkitt lymphoma cell line (Namalwa).  The techniques demonstrated are useful for a wide range of siRNA-based experiments on both adherent and suspension cells.  We will also show how to streamline cell counting with the TC10 automated cell counter, how to electroporate multiple samples simultaneously using the MXcell electroporation system, and how to simultaneously assess RNA quality and quantity with the Experion automated electrophoresis system.

This procedure describes a quick and easy workflow to introduce siRNA into difficult to transfect cell lines and follow gene expression by real-time PCR. Use of an automated cell counter, multi-well electroporation plate, and automated electrophoresis station provide quick and reliable results without the need for expensive robotic handling.

El uso de un contador de células automatizado para simplificar estudios de expresión génica: siRNA Derribo de IL-4 la expresión génica en células dependientes Namalwa

The use of siRNA mediated gene knockdown is continuing to be an important tool in studies of gene expression.  siRNA studies are being conducted not only ...

In vitro Reconstitution of the Active T. castaneum Telomerase

Efforts to isolate the catalytic subunit of telomerase, TERT, in sufficient quantities for structural studies, have been met with limited success for more than a decade. Here, we present methods for the isolation of the recombinant Tribolium castaneum TERT (TcTERT) and the reconstitution of the active T. castaneum telomerase ribonucleoprotein (RNP) complex in vitro.
Telomerase is a specialized reverse transcriptase1 that adds short DNA repeats, called telomeres, to the 3' end of linear chromosomes2 that serve to protect them from end-to-end fusion and degradation. Following DNA replication, a short segment is lost at the end of the chromosome3 and without telomerase, cells continue dividing until eventually reaching their Hayflick Limit4. Additionally, telomerase is dormant in most somatic cells5 in adults, but is active in cancer cells6 where it promotes cell immortality7.
The minimal telomerase enzyme consists of two core components: the protein subunit (TERT), which comprises the catalytic subunit of the enzyme and an integral RNA component (TER), which contains the template TERT uses to synthesize telomeres8,9. Prior to 2008, only structures for individual telomerase domains had been solved10,11. A major breakthrough in this field came from the determination of the crystal structure of the active12, catalytic subunit of T. castaneum telomerase, TcTERT1.
Here, we present methods for producing large quantities of the active, soluble TcTERT for structural and biochemical studies, and the reconstitution of the telomerase RNP complex in vitro for telomerase activity assays. An overview of the experimental methods used is shown in Figure 1.

In vitro Reconstitution of the Active T. castaneum Telomerase

Efforts to isolate the catalytic subunit of telomerase, TERT, in sufficient quantities for structural studies, have been met with limited success for more than a decade. Here, we present methods for the isolation of the recombinant Tribolium castaneum TERT (TcTERT) and the reconstitution of the active T. castaneum telomerase ribonucleoprotein (RNP) complex in vitro.

En la reconstitución in vitro de los activos T. castaneum telomerasa

Efforts to isolate the catalytic subunit of telomerase, TERT, in sufficient quantities for structural studies, have been met with limited success for more ...

A High Throughput in situ Hybridization Method to Characterize mRNA Expression Patterns in the Fetal Mouse Lower Urogenital Tract

Development of the lower urogenital tract (LUT) is an intricate process. This complexity is evidenced during formation of the prostate from the fetal male urethra, which relies on androgenic signals and epithelial-mesenchymal interactions1,2. Understanding the molecular mechanisms responsible for prostate development may reveal growth mechanisms that are inappropriately reawakened later in life to give rise to prostate diseases such as benign prostatic hyperplasia and prostate cancer.
The developing LUT is anatomically complex. By the time prostatic budding begins on 16.5 days post conception (dpc), numerous cell types are present. Vasculature, nerves and smooth muscle reside within the mesenchymal stroma3. This stroma surrounds a multilayered epithelium and gives rise to the fetal prostate through androgen receptor-dependent paracrine signals4. The identity of the stromal androgen receptor-responsive genes required for prostate development and the mechanism by which prostate ductal epithelium forms in response to these genes is not fully understood. The ability to precisely identify cell types and localize expression of specific factors within them is imperative to further understand prostate development. In situ hybridization (ISH) allows for localization of mRNAs within a tissue. Thus, this method can be used to identify pattern and timing of expression of signaling molecules and their receptors, thereby elucidating potential prostate developmental regulators.
Here, we describe a high throughput ISH technique to identify mRNA expression patterns in the fetal mouse LUT using vibrating microtome-cut sections. This method offers several advantages over other ISH protocols. Performing ISH on thin sections adhered to a slide is technically difficult; cryosections frequently have poor structural quality while both cryosections and paraffin sections often result in weak signal resolution. Performing ISH on whole mount tissues can result in probe trapping. In contrast, our high throughput technique utilizes thick-cut sections that reveal detailed tissue architecture. Modified microfuge tubes allow easy handling of sections during the ISH procedure. A maximum of 4 mRNA transcripts can be screened from a single 17.5dpc LUT with up to 24 mRNA transcripts detected in a single run, thereby reducing cost and maximizing efficiency. This method allows multiple treatment groups to be processed identically and as a single unit, thereby removing any bias for interpreting data. Most pertinently for prostate researchers, this method provides a spatial and temporal location of low and high abundance mRNA transcripts in the fetal mouse urethra that gives rise to the prostate ductal network.

A High Throughput in situ Hybridization Method to Characterize mRNA Expression Patterns in the Fetal Mouse Lower Urogenital Tract

Here, we describe an efficient high throughput in situ hybridization (ISH) method for visualizing patterns of mRNA expression in developing fetal mouse prostate tissue sections. The method can be easily adapted to visualize mRNA expression patterns in other mouse tissues or in tissues from other species.

Un alto rendimiento In situ Método de hibridación para caracterizar los patrones de expresión de ARNm en el ratón Fetal del tracto urogenital inferior

Development of the lower urogenital tract (LUT) is an intricate process. This complexity is evidenced during formation of the prostate from the fetal male ...

Analysis of Single-cell Gene Transcription by RNA Fluorescent In Situ Hybridization (FISH)

Adhesion of Plasmodium falciparum infected erythrocytes (IE) to human endothelial receptors during malaria infections is mediated by expression of PfEMP1 protein variants encoded by the var genes.
The haploid P. falciparum genome harbors approximately 60 different var genes of which only one has been believed to be transcribed per cell at a time during the blood stage of the infection. How such mutually exclusive regulation of var gene transcription is achieved is unclear, as is the identification of individual var genes or sub-groups of var genes associated with different receptors and the consequence of differential binding on the clinical outcome of P. falciparum infections. Recently, the mutually exclusive transcription paradigm has been called into doubt by transcription assays based on individual P. falciparum transcript identification in single infected erythrocytic cells using RNA fluorescent in situ hybridization (FISH) analysis of var gene transcription by the parasite in individual nuclei of P. falciparum IE1.
Here, we present a detailed protocol for carrying out the RNA-FISH methodology for analysis of var gene transcription in single-nuclei of P. falciparum infected human erythrocytes. The method is based on the use of digoxigenin- and biotin- labeled antisense RNA probes using the TSA Plus Fluorescence Palette System2 (Perkin Elmer), microscopic analyses and freshly selected P. falciparum IE. The in situ hybridization method can be used to monitor transcription and regulation of a variety of genes expressed during the different stages of the P. falciparum life cycle and is adaptable to other malaria parasite species and other organisms and cell types.

Analysis of Single-cell Gene Transcription by RNA Fluorescent In Situ Hybridization FISH

Fluorescent in situ hybridization (FISH) to identify mRNA transcripts in individual cells allows analysis of polygenic activity such as the simultaneous transcription of more than one member of the var multigene family in Plasmodium falciparum infected erythrocytes 1. The technique is adaptable and can be used on different types of genes, cells and organisms.

Análisis de la transcripción de genes de una sola célula de ARN fluorescente<em&gt; In Situ</em&gt; La hibridación (FISH)

Adhesion of Plasmodium falciparum infected erythrocytes (IE) to human endothelial receptors during malaria infections is mediated by expression of PfEMP1 ...

Visualization and Analysis of mRNA Molecules Using Fluorescence In Situ Hybridization in Saccharomyces cerevisiae

The Fluorescence in situ Hybridization (FISH) method allows one to detect nucleic acids in the native cellular environment. Here we provide a protocol for using FISH to quantify the number of mRNAs in single yeast cells. Cells can be grown in any condition of interest and then fixed and made permeable. Subsequently, multiple single-stranded deoxyoligonucleotides conjugated to fluorescent dyes are used to label and visualize mRNAs. Diffraction-limited fluorescence from single mRNA molecules is quantified using a spot-detection algorithm to identify and count the number of mRNAs per cell. While the more standard quantification methods of northern blots, RT-PCR and gene expression microarrays provide information on average mRNAs in the bulk population, FISH facilitates both the counting and localization of these mRNAs in single cells at single-molecule resolution.

Visualization and Analysis of mRNA Molecules Using Fluorescence In Situ Hybridization in Saccharomyces cerevisiae

This protocol describes an experimental procedure for performing Fluorescence in situ Hybridization (FISH) for counting mRNAs in single cells at single-molecule resolution.

Visualización y Análisis de las moléculas de ARNm mediante fluorescencia<em&gt; In Situ</em&gt; La hibridación en<em&gt; Saccharomyces cerevisiae</em

The Fluorescence in situ Hybridization (FISH) method allows one to detect nucleic acids in the native cellular environment. Here we provide a protocol for ...

High Resolution Whole Mount In Situ Hybridization within Zebrafish Embryos to Study Gene Expression and Function

This article focuses on whole-mount in situ hybridization (WISH) of zebrafish embryos. The WISH technology facilitates the assessment of gene expression both in terms of tissue distribution and developmental stage. Protocols are described for the use of WISH of zebrafish embryos using antisense RNA probes labeled with digoxigenin. Probes are generated by incorporating digoxigenin-linked nucleotides through in vitro transcription of gene templates that have been cloned and linearized. The chorions of embryos harvested at defined developmental stages are removed before incubation with specific probes. Following a washing procedure to remove excess probe, embryos are incubated with anti-digoxigenin antibody conjugated with alkaline phosphatase. By employing a chromogenic substrate for alkaline phosphatase, specific gene expression can be assessed. Depending on the level of gene expression the entire procedure can be completed within 2-3 days.

High Resolution Whole Mount In Situ Hybridization within Zebrafish Embryos to Study Gene Expression and Function

The zebrafish, a small tropical fish, has become a popular model for studying gene function during vertebrate development and disease. The temporal and spatial expression of target genes can be determined by in situ hybridization. Our improved protocol allows for the detection of low abundant transcripts with low non-specific background signal.

Alta resolución todo el montaje de<em&gt; In Situ</em&gt; La hibridación en embriones de pez cebra para estudiar la expresión génica y la función

This article focuses on whole-mount in situ hybridization (WISH) of zebrafish embryos. The WISH technology facilitates the assessment of gene expression ...

MicroRNA In situ Hybridization for Formalin Fixed Kidney Tissues

In this article we describe a method for colorimetric detection of miRNA in the kidney through in situ hybridization with digoxigenin tagged microRNA probes. This protocol, originally developed by Kloosterman and colleagues for broad use with Exiqon miRNA probes1, has been modified to overcome challenges inherent in miRNA analysis in kidney tissues. These include issues such as structure identification and hard to remove residual probe and antibody. Use of relatively thin, 5 mm thick, tissue sections allowed for clear visualization of kidney structures, while a strong probe signal was retained in cells. Additionally, probe concentration and incubation conditions were optimized to facilitate visualization of microRNA expression with low background and nonspecific signal. Here, the optimized protocol is described, covering the initial tissue collection and preparation through the mounting of slides at the end of the procedure. The basic components of this protocol can be altered for application to other tissues and cell culture models.

MicroRNA In situ Hybridization for Formalin Fixed Kidney Tissues

This article describes an in situ hybridization protocol optimized for colormetric detection of microRNA expression in formalin fixed kidney sections.

MicroRNA<em&gt; In situ</em&gt; La hibridación de los tejidos del riñón y fijados con formalina

In this article we describe a method for colorimetric detection of miRNA in the kidney through in situ hybridization with digoxigenin tagged microRNA ...