Agradecemos a Gary Laevsky útil para los debates sobre la microscopía. Este trabajo fue financiado por el NIH subvenciones R01GM061107 y R01GM067758 a ERG

Nota: El procedimiento para la eliminación de músculo (Figura 1) es una modificación de los métodos descritos anteriormente para la preparación de filetes de larvas. Los pasos que preceden y siguen a la eliminación del músculo se describen brevemente y se remite al lector a los trabajos previos 10, 11 para una descripción más detallada. 1. Dissect Larva en solución salina fría <ol><li> Preparar una dilución de trabajo de solución salina fría HL3.1 15 o Ca 2 + libre frío HL3.1 solución salina 11 (Tabla 1). Coloque la larva en una placa de elastómero de silicona con suficiente solución salina fría para cubrir el fondo del plato. Nota: Véase la discusión con respecto a la elección de la solución salina. </li></ol><table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always"><tbody><tr><td> solución salina HL3.1 1x (pH 7,2) </td></tr><tr><td> HEPES 5 mM </td></tr><tr><td> NaCl 70 mM </td></tr><tr&gt; <td> KCl 5 mM </td></tr><tr><td> 1,5 mM de CaCl2 (omitir para Ca2 + solución salina exento) </td></tr><tr><td> 4 mM MgCl2 </td></tr><tr><td> 10 mM NaHCO 3 </td></tr><tr><td> trehalosa 5 mM </td></tr><tr><td> sacarosa 115 mM </td></tr><tr><td></td></tr><tr><td> Se esteriliza con filtro y se almacena a 4 ° C </td></tr><tr><td> imita la composición de insectos hemolinfa: Nota </td></tr></tbody></table> Tabla 1. Composición de frío Saline. <ol start="2"><li> Coloque la larva con el lado ventral hacia arriba. La superficie ventral de la larva se puede identificar por las cintas dentical abdominales y el lado dorsal por los tubos traqueales larvas primarias que funcionan de anterior a posterior. Estirar la larva en la dirección antero-posterior y el pin de la cabeza y la cola a unaelastómero de silicona disección plato usando pasadores de insectos. Con unas tijeras de disección finas para cortar a lo largo de la línea media ventral, comenzando en un extremo y progresando hacia el otro. NOTA: Esta orientación conserva el clúster dorsal comúnmente estudiada de las neuronas DA. </li><li> Después de la larva se corta abierta, fijar las cuatro esquinas del plato a la disección como si la apertura de un libro. El uso de fórceps para agarrar y extraer los órganos internos, incluyendo el sistema nervioso central, intestino, y la tráquea. Ajuste pasadores de insectos de manera que el filete es tensa pero no estirada al máximo. NOTA: Los músculos están ancladas a la pared del cuerpo en los límites segmentarias. Aunque los músculos cubren la mayor parte de la pared del cuerpo, que están ausentes en una zona estrecha cerca de la línea media dorsal. </li></ol> La eliminación 2. Músculo <ol><li> Busque la línea media dorsal de la larva, donde el tejido muscular está ausente. Coloque un solo diente fórceps de tal manera que se puede insertar debajo del tejido muscular en la orientación más plana posible. </li><li> A partir dela línea media dorsal, cerca del límite anterior del segmento, deslice cuidadosamente el diente fórceps entre el músculo y la epidermis, teniendo cuidado para minimizar el contacto entre la pinza y la epidermis. </li><li> Tire de la pinza hacia arriba para romper la unión del músculo para la pared del cuerpo en un punto de anclaje. Repita este proceso para el hemi-segmento (s) restante de interés. NOTA: Este protocolo optimiza la preservación de la parte posterior de cada campo de dendritas de las neuronas DA. Para preservar la parte anterior del campo de dendritas, lo mejor es insertar la clavija de fórceps en el extremo posterior de cada segmento. </li><li> Reajustar pasadores de insectos tales que el filete de larvas se estira al máximo en todas las direcciones. </li><li> Fijar el filete mientras que todavía se fija en el plato de disección usando, recién preparada formaldehído frío 4% en PBS durante 25 min. </li><li> Enjuagar 5 veces en PBS. </li><li> El uso de fórceps para extraer con cuidado el tejido muscular de los restantes puntos de anclaje, teniendo cuidado para minimizar contact con la epidermis. </li><li> Desanclar y quitar el filete del plato de la disección a un tubo de microcentrífuga de 1,5 ml. Llevar a cabo todas lavado, bloqueo, y los pasos de tinción de inmunofluorescencia posteriores, como se describió anteriormente 11. </li></ol> 3. Monte el filete de larvas <ol><li> Saca primero la cabeza y la cola con unas tijeras de disección finas con el fin de hacer la muestra lo más plana posible. Montar el filete en un cubreobjetos en medio de montaje antifade con la superficie interior del filete frente al cubreobjetos. </li><li> Colocar un portaobjetos de microscopio en el cubreobjetos y presionar suavemente para dispersar el medio de montaje. Da la vuelta al portaobjetos de microscopio una y sellar el cubreobjetos sobre el portaobjetos usando esmalte de uñas. Las diapositivas se pueden almacenar a -20 ° C durante al menos un mes. </li></ol>

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	<li>Jan, Y. N., Jan, L. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Branching+out:+mechanisms+of+dendritic+arborization.">Branching out: mechanisms of dendritic arborization.</a> Nat Rev Neurosci. 11 (5), 316-328 (2010).</li><li>Corty, M. M., Matthews, B. J., Grueber, W. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecules+and+mechanisms+of+dendrite+development+in+Drosophila.">Molecules and mechanisms of dendrite development in Drosophila.</a> Development. 136 (7), 1049-1061 (2009).</li><li>Parrish, J. Z., Emoto, K., Kim, M. D., Jan, Y. 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B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Integrins+establish+dendrite-substrate+relationships+that+promote+dendritic+self-avoidance+and+patterning+in+Drosophila+sensory+neurons.">Integrins establish dendrite-substrate relationships that promote dendritic self-avoidance and patterning in Drosophila sensory neurons.</a> Neuron. 73 (1), 79-91 (2012).</li><li>Han, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Integrins+regulate+repulsion-mediated+dendritic+patterning+of+Drosophila+sensory+neurons+by+restricting+dendrites+in+a+2D+space.">Integrins regulate repulsion-mediated dendritic patterning of Drosophila sensory neurons by restricting dendrites in a 2D space.</a> Neuron. 73 (1), 64-78 (2012).</li><li>Parrish, J. Z., Xu, P., Kim, C. C., Jan, L. Y., Jan, Y. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+microRNA+bantam+functions+in+epithelial+cells+to+regulate+scaling+growth+of+dendrite+arbors+in+Drosophila+sensory+neurons.">The microRNA bantam functions in epithelial cells to regulate scaling growth of dendrite arbors in Drosophila sensory neurons.</a> Neuron. 63 (6), 788-802 (2009).</li><li>Jiang, N., Soba, P., Parker, E., Kim, C. C., Parrish, J. Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+microRNA+bantam+regulates+a+developmental+transition+in+epithelial+cells+that+restricts+sensory+dendrite+growth.">The microRNA bantam regulates a developmental transition in epithelial cells that restricts sensory dendrite growth.</a> Development. 141 (13), 2657-2668 (2014).</li><li>Meltzer, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epidermis-derived+Semaphorin+promotes+dendrite+self-avoidance+by+regulating+dendrite-substrate+adhesion+in+Drosophila+sensory+neurons.">Epidermis-derived Semaphorin promotes dendrite self-avoidance by regulating dendrite-substrate adhesion in Drosophila sensory neurons.</a> Neuron. 89 (4), 741-755 (2016).</li><li>Han, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epidermal+cells+are+the+primary+phagocytes+in+the+fragmentation+and+clearance+of+degenerating+dendrites+in+Drosophila.">Epidermal cells are the primary phagocytes in the fragmentation and clearance of degenerating dendrites in Drosophila.</a> Neuron. 81 (3), 544-560 (2014).</li><li>Brent, J. R., Werner, K. M., McCabe, B. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drosophila+larval+NMJ+dissection.">Drosophila larval NMJ dissection.</a> J Vis Exp. (24), (2009).</li><li>Karim, M. R., Moore, A. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphological+analysis+of+Drosophila+larval+peripheral+sensory+neuron+dendrites+and+axons+using+genetic+mosaics.">Morphological analysis of Drosophila larval peripheral sensory neuron dendrites and axons using genetic mosaics.</a> J Vis Exp. (57), e3111 (2011).</li><li>Gustafsson, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surpassing+the+lateral+resolution+limit+by+a+factor+of+two+using+structured+illumination+microscopy.">Surpassing the lateral resolution limit by a factor of two using structured illumination microscopy.</a> J Microscopy. 198 (2), 82-87 (2000).</li><li>Ashdown, G. W., Cope, A., Wiseman, P. W., Owen, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+flow+quantified+beyond+the+diffraction+limit+by+spatiotemporal+image+correlation+of+structured+illumination+microscopy+data.">Molecular flow quantified beyond the diffraction limit by spatiotemporal image correlation of structured illumination microscopy data.</a> Biophys J. 107 (9), L21-L23 (2014).</li><li>Zhang, W., Yan, Z., Jan, L. Y., Jan, Y. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sound+response+mediated+by+the+TRP+channels+NOMPC,+NANCHUNG,+and+INACTIVE+in+chordotonal+organs+of+Drosophila+larvae.">Sound response mediated by the TRP channels NOMPC, NANCHUNG, and INACTIVE in chordotonal organs of Drosophila larvae.</a> PNAS. 10 (33), 13612-13617 (2013).</li><li>Feng, Y., Ueda, A., Wu, C. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+modified+minimal+hemolymph-like+solution,+HL3.1,+for+physiological+recordings+at+the+neuromuscular+junctions+of+normal+and+mutant+Drosophila+larvae.">A modified minimal hemolymph-like solution, HL3.1, for physiological recordings at the neuromuscular junctions of normal and mutant Drosophila larvae.</a> J Neurogenet. 18 (2), 377-402 (2004).</li><li>Babcock, D. T., Landry, C., Galko, M. 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Los autores no tienen nada que revelar.

Aquí un protocolo se describe para la extracción manual de tejido muscular de Drosophila filetes de larvas. Este protocolo descrito previamente modifica la técnica de disección de las larvas 10,11. Después de la larva se diseca en una placa de elastómero de silicona, la línea media dorsal se encuentra. Una sola pinzas de punta, en su orientación más plana posible, se inserta cuidadosamente entre el tejido muscular y la epidermis, cerca de la línea media dorsal. El fórceps se tira suavement...

Arborización dendrítica (da), las neuronas de larvas de Drosophila proporcionan un modelo valioso para el estudio del desarrollo neuronal debido a su susceptibilidad a la manipulación genética y la facilidad con la que pueden obtenerse imágenes. Estas neuronas sensoriales han sido instrumentales en la identificación de numerosas vías que controlan la morfogénesis de dendritas 1-3. Cuatro clases de neuronas DA (clase I - IV) inervar la epidermis de las larvas. Estas neuronas se encuentran entre la membrana basal y la epidermis, con sus dendritas formando matrices en gran medida de dos dimensiones 4,5. De las cuatro clases, clase IV da neuronas tienen las glorietas más altamente ramificada y, al igual que las neuronas sensoriales de otros animales, la elaboración de estas pérgolas requiere factores intrínsecos, así como las señales de los tejidos vecinos, particularmente en la epidermis, para su desarrollo 6-9 . Los estudios para determinar las modalidades de dicha neuronal y hecho de extra-neuronalORS controlar beneficio morfogénesis dendrita de la capacidad de detectar la expresión de proteínas in situ por inmunofluorescencia. La cutícula exterior de la larva es impenetrable a los anticuerpos, pero este impedimento es fácilmente superada por la preparación de filetes de larvas a través de métodos de disección bien establecidos 10,11. Sin embargo, el tejido muscular de la pared del cuerpo que se encuentra justo interior a la membrana basal presenta varios retos hacia la visualización de las neuronas DA y las células epidérmicas. En primer lugar, el tejido muscular, lo que la mayoría de las líneas de la pared del cuerpo, oscurece considerablemente señales fluorescentes que emanan de tejido neuronal o epidérmica. Esto reduce sustancialmente la relación señal a ruido en la muestra. En segundo lugar, muchas proteínas relevantes pueden expresarse en el tejido muscular, así como en las neuronas o epidermis. Esta señal de fluorescencia derivada de músculo es probable que aún más la detección oscura de una señal de fluorescencia de la neurona o epidermis. Por último, los avances en las tecnologías de microscopía sinw imágenes permiso de muestras a una resolución de sub-difracción y puede ser especialmente útil en el discernimiento de la localización de las proteínas que se expresan en las neuronas y células de la epidermis que rodea 12,13. Sin embargo, las imágenes a través de super-resolución de microscopía se beneficia de una fuerte relación señal a ruido y la proximidad de la muestra al cubreobjetos. Además de reducir la relación señal a ruido, la pared del cuerpo distancias musculares larvas da a las neuronas de la cubreobjetos, limitando de este modo la resolución de imagen mejorado que se puede conseguir con métodos de microscopía super-resolución. Además de retos para el análisis de inmunofluorescencia, el tejido muscular presenta una barrera para el registro electrofisiológico de las neuronas sensoriales en la pared corporal de larvas. Por tanto, su eliminación se beneficia manipulación neurofisiológica de las neuronas sensoriales 14. Aquí se describe un método para la extracción manual de Drosophila tejido muscular larval. Se demuestra que nuestro protocolo permits de formación de imágenes de inmunofluorescencia de las proteínas que se oscurece de otra manera por el tejido muscular, mejora la relación señal a ruido para la visualización de clase IV neuronas DA, y permite el uso de super-resolución microscopía para discriminar mejor las relaciones espaciales de proteínas y estructuras celulares en Da neuronas y la epidermis.

<table border="0" cellpadding="0" cellspacing="0" width="1299">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:413px;">Dumont #5 tweezers</td>
			<td style="width:304px;">Electron Microscopy Sciences</td>
			<td style="width:151px;">72701-D</td>
			<td style="width:432px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Micro Scissors, 8 cm, straight, 5 mm blades, 0.1 mm tips</td>
			<td>World Precision Instruments</td>
			<td>14003</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sylgard 184 silicone elastomer kit</td>
			<td>Dow Corning</td>
			<td>3097358-1004</td>
			<td>for dissecting plates</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Austerlitz insect pins, 0.1 mm</td>
			<td>Fine Science Tools</td>
			<td>26002-10</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Fostec 8375 light source</td>
			<td>Artisan Technology Group</td>
			<td>62792-4</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Zeiss Stemi 2000</td>
			<td>Carl Zeiss Microscopy</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Vectashield antifade mounting medium</td>
			<td>Vector Laboratories</td>
			<td>H-1000</td>
			<td>for confocal microscopy</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Prolong Diamond antifade mountant</td>
			<td>Life Technologies</td>
			<td>P36970</td>
			<td>for structured illumination microscopy</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Micro cover glass, 22x22 mm, No. 1.5</td>
			<td>VWR</td>
			<td>48366-227</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Superfrost Plus microscope slides, 25 x 75 x 1.0 mm</td>
			<td>Fisherbrand</td>
			<td>12-550-15</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Mouse anti-Coracle antibody</td>
			<td>Developmental Studies Hybridoma Bank</td>
			<td>C615.16</td>
			<td>supernatant, dilute 1:50</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Mouse anti-Discs large antibody</td>
			<td>Developmental Studies Hybridoma Bank</td>
			<td>4F3</td>
			<td>supernatant, dilute 1:50</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Rabbit anti-dsRed antibody</td>
			<td>Clontech</td>
			<td>632496</td>
			<td>dilute 1:1000</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Goat anti-rabbit antibody, Alexa Fluor 568 conjugated</td>
			<td>ThermoFisher Scientific</td>
			<td>A-11011</td>
			<td>dilute 1:1000</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Goat anti-mouse antibody, Alexa Fluor 488 conjugated</td>
			<td>ThermoFisher Scientific</td>
			<td>A-11001</td>
			<td>dilute 1:500</td>
		</tr>
	</tbody>
</table>

removal of drosophila muscle tissue from larval fillets for immunofluorescence analysis of sensory neurons and epidermal cells

Arborización dendrítica (DA), las neuronas de larvas de Drosophila son un modelo popular para la investigación de los mecanismos de morfogénesis neuronal. Da neuronas desarrollan en comunicación con las células epidérmicas que inervan y por tanto su análisis de beneficios de la visualización in situ de las dos proteínas expresadas neuronalmente y epidérmicamente por inmunofluorescencia. Los métodos tradicionales de preparación de filetes de larvas para experimentos de inmunofluorescencia dejan intacto el tejido muscular que cubre la mayor parte de la pared del cuerpo, que presenta varios desafíos para la formación de imágenes proteínas neuronales y epidérmicas. Aquí se describe un método para eliminar el tejido muscular de Drosophila filetes de larvas. Este protocolo permite que las imágenes de las proteínas que se oscurece de otra manera por el tejido muscular, mejora la relación señal a ruido, y facilita el uso de super-resolución microscopía para estudiar da el desarrollo de la neurona.

Se demuestra la utilidad del procedimiento de extracción muscular para mejorar la relación señal a ruido en los experimentos de inmunofluorescencia para co-visualizar las proteínas de unión tabicado Coracle (Cora) y discos de gran (DLG), junto con la clase IV neuronas DA, marcadas con el marcador de membrana CD4 tdTomato. Cora se ha utilizado anteriormente para identificar áreas de muestreo donde da las dendritas de las neuronas están rodeados por cél...

Watch this Scientific Journal Video about Removal of Drosophila Muscle Tissue from Larval Fillets for Immunofluorescence Analysis of Sensory Neurons and Epidermal Cells at JoVE.com

Removal of Drosophila Muscle Tissue from Larval Fillets for Immunofluorescence Analysis of Sensory Neurons and Epidermal Cells

Los estudios de la morfogénesis neuronal utilizando Drosophila arborización dendrítica larval (DA) se benefician de las neuronas en la visualización in situ de las proteínas neuronales y epidérmicas por inmunofluorescencia. Se describe un procedimiento que mejora el análisis de inmunofluorescencia de DA neuronas y las células epidérmicas que rodean mediante la eliminación de tejido muscular de la pared del cuerpo de la larva.

Eliminación de<em&gt; Drosophila</em&gt; Tejido muscular de larvas Filetes para el análisis de inmunofluorescencia de las neuronas sensoriales y las células epidérmicas

Drosophila larval dendritic arborization (da) neurons are a popular model for investigating mechanisms of neuronal morphogenesis. Da neurons develop in ...

removal-drosophila-muscle-tissue-from-larval-fillets-for

Research

JoVE Journal

Neuroscience

Removal of Drosophila Muscle Tissue from Larval Fillets for Immunofluorescence Analysis of Sensory Neurons and Epidermal Cells

8.9K vistas.  Princeton University.  Los estudios de la morfogénesis neuronal utilizando Drosophila arborización dendrítica larval (DA) se benefician de las neuronas en la visualización in situ de las proteínas neuronales y epidérmicas por inmunofluorescencia. Se describe un procedimiento que mejora el análisis de inmunofluorescencia de DA neuronas y las células epidérmicas que rodean mediante la eliminación de tejido muscular de la pared del cuerpo de la larva. 

Video: Removal of Drosophila Muscle Tissue from Larval Fillets for Immunofluorescence Analysis of Sensory Neurons and Epidermal Cells

Live-cell Imaging of Sensory Organ Precursor Cells in Intact Drosophila Pupae

Since the discovery of Green Fluorescent Protein (GFP), there has been a revolutionary change in the use of live-cell imaging as a tool for understanding fundamental biological mechanisms. Striking progress has been particularly evident in Drosophila, whose extensive toolkit of mutants and transgenic lines provides a convenient model to study evolutionarily-conserved developmental and cell biological mechanisms. We are interested in understanding the mechanisms that control cell fate specification in the adult peripheral nervous system (PNS) in Drosophila. Bristles that cover the head, thorax, abdomen, legs and wings of the adult fly are individual mechanosensory organs, and have been studied as a model system for understanding mechanisms of Notch-dependent cell fate decisions. Sensory organ precursor (SOP) cells of the microchaetes (or small bristles), are distributed throughout the epithelium of the pupal thorax, and are specified during the first 12 hours after the onset of pupariation. After specification, the SOP cells begin to divide, segregating the cell fate determinant Numb to one daughter cell during mitosis. Numb functions as a cell-autonomous inhibitor of the Notch signaling pathway.
Here, we show a method to follow protein dynamics in SOP cell and its progeny within the intact pupal thorax using a combination of tissue-specific Gal4 drivers and GFP-tagged fusion proteins 1,2.This technique has the advantage over fixed tissue or cultured explants because it allows us to follow the entire development of an organ from specification of the neural precursor to growth and terminal differentiation of the organ. We can therefore directly correlate changes in cell behavior to changes in terminal differentiation. Moreover, we can combine the live imaging technique with mosaic analysis with a repressible cell marker (MARCM) system to assess the dynamics of tagged proteins in mitotic SOPs under mutant or wildtype conditions. Using this technique, we and others have revealed novel insights into regulation of asymmetric cell division and the control of Notch signaling activation in SOP cells (examples include references 1-6,7 ,8).

Live-cell Imaging of Sensory Organ Precursor Cells in Intact Drosophila Pupae

In this video, we describe a method for live cell imaging of asymmetrically dividing sensory organ progenitor cells and epidermal cells in intact Drosophila pupae

Células vivas imágenes de células de los órganos sensoriales Precursor en Intacto Drosophila Las pupas

Since the discovery of Green Fluorescent Protein (GFP), there has been a revolutionary change in the use of live-cell imaging as a tool for understanding ...

Investigación

Neurociencias

Morphological Analysis of Drosophila Larval Peripheral Sensory Neuron Dendrites and Axons Using Genetic Mosaics

Nervous system development requires the correct specification of neuron position and identity, followed by accurate neuron class-specific dendritic development and axonal wiring. Recently the dendritic arborization (DA) sensory neurons of the Drosophila larval peripheral nervous system (PNS) have become powerful genetic models in which to elucidate both general and class-specific mechanisms of neuron differentiation.
There are four main DA neuron classes (I-IV)1. They are named in order of increasing dendrite arbor complexity, and have class-specific differences in the genetic control of their differentiation2-10. The DA sensory system is a practical model to investigate the molecular mechanisms behind the control of dendritic morphology11-13 because: 1) it can take advantage of the powerful genetic tools available in the fruit fly, 2) the DA neuron dendrite arbor spreads out in only 2 dimensions beneath an optically clear larval cuticle making it easy to visualize with high resolution in vivo, 3) the class-specific diversity in dendritic morphology facilitates a comparative analysis to find key elements controlling the formation of simple vs. highly branched dendritic trees, and 4) dendritic arbor stereotypical shapes of different DA neurons facilitate morphometric statistical analyses.
DA neuron activity modifies the output of a larval locomotion central pattern generator14-16. The different DA neuron classes have distinct sensory modalities, and their activation elicits different behavioral responses14,16-20. Furthermore different classes send axonal projections stereotypically into the Drosophila larval central nervous system in the ventral nerve cord (VNC)21. These projections terminate with topographic representations of both DA neuron sensory modality and the position in the body wall of the dendritic field7,22,23. Hence examination of DA axonal projections can be used to elucidate mechanisms underlying topographic mapping7,22,23, as well as the wiring of a simple circuit modulating larval locomotion14-17.
We present here a practical guide to generate and analyze genetic mosaics24 marking DA neurons via MARCM (Mosaic Analysis with a Repressible Cell Marker)1,10,25 and Flp-out22,26,27 techniques (summarized in Fig. 1).

Morphological Analysis of Drosophila Larval Peripheral Sensory Neuron Dendrites and Axons Using Genetic Mosaics

The dendritic arborization sensory neurons of the Drosophila larval peripheral nervous system are useful models to elucidate both general and neuron class-specific mechanisms of neuron differentiation. We present a practical guide to generate and analyze dendritic arborization neuron genetic mosaics.

Análisis morfológico de Drosophila Larvas dendritas neurona sensorial periférica y axones Con mosaicos genéticos

Nervous system development requires the correct specification of neuron position and identity, followed by accurate neuron class-specific dendritic ...

Dissection and Immunohistochemistry of Larval, Pupal and Adult Drosophila Retinas

The compound eye of Drosophila melanogaster consists of about 750 ommatidia (unit eyes). Each ommatidium is composed of about 20 cells, including lens-secreting cone cells, pigment cells, a bristle cell and eight photoreceptors (PRs) R1-R8 2. The PRs have specialized microvillar structures, the rhabdomeres, which contain light-sensitive pigments, the Rhodopsins (Rhs). The rhabdomeres of six PRs (R1-R6) form a trapezoid and contain Rh1 3 4. The rhabdomeres of R7 and R8 are positioned in tandem in the center of the trapezoid and share the same path of light. R7 and R8 PRs stochastically express different combinations of Rhs in two main subtypes5: In the 'p' subtype, Rh3 in pR7s is coupled with Rh5 in pR8s, whereas in the 'y' subtype, Rh4 in yR7s is associated with Rh6 in yR8s 6 7 8.
Early specification of PRs and development of ommatidia begins in the larval eye-antennal imaginal disc, a monolayer of epithelial cells. A wave of differentiation sweeps across the disc9 and initiates the assembly of undifferentiated cells into ommatidia10-11. The 'founder cell' R8 is specified first and recruits R1-6 and then R7 12-14. Subsequently, during pupal development, PR differentiation leads to extensive morphological changes 15, including rhabdomere formation, synaptogenesis and eventually rh expression.
In this protocol, we describe methods for retinal dissections and immunohistochemistry at three defined periods of retina development, which can be applied to address a variety of questions concerning retinal formation and developmental pathways. Here, we use these methods to visualize the stepwise PR differentiation at the single-cell level in whole mount larval, midpupal and adult retinas (Figure 1).

Dissection and Immunohistochemistry of Larval, Pupal and Adult Drosophila Retinas

The Drosophila retina is a crystal-like lattice composed of a small number of cell types that are generated in a stereotyped manner 1. Its amenability to sophisticated genetic analysis allows the study of complex developmental programs. This protocol describes dissections and immunohistochemistry of retinas at three discrete developmental stages, with a focus on photoreceptor differentiation.

La disección e inmunohistoquímica de larva, pupa y adulto<em&gt; Drosophila</em&gt; Retinas

The compound eye of Drosophila melanogaster consists of about 750 ommatidia (unit eyes). Each ommatidium is composed of about 20 cells, including ...

Functional Analysis of the Larval Feeding Circuit in Drosophila

The serotonergic feeding circuit in Drosophila melanogaster larvae can be used to investigate neuronal substrates of critical importance during the development of the circuit. Using the functional output of the circuit, feeding, changes in the neuronal architecture of the stomatogastric system can be visualized. Feeding behavior can be recorded by observing the rate of retraction of the mouth hooks, which receive innervation from the brain. Locomotor behavior is used as a physiological control for feeding, since larvae use their mouth hooks to traverse across an agar substrate. Changes in feeding behavior can be correlated with the axonal architecture of the neurites innervating the gut. Using immunohistochemistry it is possible to visualize and quantitate these changes. Improper handling of the larvae during behavior paradigms can alter data as they are very sensitive to manipulations. Proper imaging of the neurite architecture innervating the gut is critical for precise quantitation of number and size of varicosities as well as the extent of branch nodes. Analysis of most circuits allow only for visualization of neurite architecture or behavioral effects; however, this model allows one to correlate the functional output of the circuit with the impairments in neuronal architecture.

Functional Analysis of the Larval Feeding Circuit in Drosophila

The feeding circuit in Drosophila melanogaster larvae serves a simple yet powerful model that allows changes in feeding rate to be correlated with alterations in the stomatogastric neural circuitry. This circuit is composed of central serotonergic neurons that send projections to the mouth hooks as well as the foregut.

Análisis funcional del circuito de alimentación de las larvas en Drosophila</i

The serotonergic  feeding circuit in Drosophila  melanogaster larvae can be used to investigate neuronal substrates of  critical importance during the ...

Whole Mount Immunolabeling of Olfactory Receptor Neurons in the Drosophila Antenna

Odorant molecules bind to their target receptors in a precise and coordinated manner. Each receptor recognizes a specific signal and relays this information to the brain. As such, determining how olfactory information is transferred to the brain, modifying both perception and behavior, merits investigation. Interestingly, there is emerging evidence that cellular transduction and transcriptional factors are involved in the diversification of olfactory receptor neuron. Here we provide a robust whole mount immunological labeling method to assay in vivo olfactory receptor neuron organization. Using this method, we identified all olfactory receptor neurons with anti-ELAV antibody, a known pan-neural marker and Or49a-mCD8::GFP, an olfactory receptor neuron specifically expressed in Nba neuron using anti-GFP antibody.

Whole Mount Immunolabeling of Olfactory Receptor Neurons in the Drosophila Antenna

Herein we describe the process of whole mount immunostaining of Drosophila antennae, which enables us to better understand the molecular mechanisms involved in the diversification of olfactory receptor neurons (ORN)s.

Todo el montaje de Immunolabeling olfativa del receptor de las neuronas en el<em&gt; Drosophila</em&gt; Antena

Odorant molecules bind to their target receptors in a precise and coordinated manner. Each receptor recognizes a specific signal and relays this ...

Live Imaging of Drosophila Larval Neuroblasts

Stem cells divide asymmetrically to generate two progeny cells with unequal fate potential: a self-renewing stem cell and a differentiating cell. Given their relevance to development and disease, understanding the mechanisms that govern asymmetric stem cell division has been a robust area of study. Because they are genetically tractable and undergo successive rounds of cell division about once every hour, the stem cells of the Drosophila central nervous system, or neuroblasts, are indispensable models for the study of stem cell division. About 100 neural stem cells are located near the surface of each of the two larval brain lobes, making this model system particularly useful for live imaging microscopy studies. In this work, we review several approaches widely used to visualize stem cell divisions, and we address the relative advantages and disadvantages of those techniques that employ dissociated versus intact brain tissues. We also detail our simplified protocol used to explant whole brains from third instar larvae for live cell imaging and fixed analysis applications.

Live Imaging of Drosophila Larval Neuroblasts

This protocol details a streamlined method used to conduct live cell imaging in the context of an intact larval brain. Live cell imaging approaches are invaluable for the study of asymmetric neural stem cell divisions as well as other neurogenic and developmental processes, consistently uncovering mechanisms that were previously overlooked.

Imágenes en vivo de<em&gt; Drosophila</em&gt; larvales neuroblastos

Stem cells divide asymmetrically to generate two progeny cells with unequal fate potential: a self-renewing stem cell and a differentiating cell. Given ...

Production and Isolation of Axons from Sensory Neurons for Biochemical Analysis Using Porous Filters

Neuronal axons use specific mechanisms to mediate extension, maintain integrity, and induce degeneration. An appropriate balance of these events is required to shape functional neuronal circuits. The protocol described here explains how to use cell culture inserts bearing a porous membrane (filter) to obtain large amounts of pure axonal preparations suitable for examination by conventional biochemical or immunocytochemical techniques. The functionality of these filter inserts will be demonstrated with models of developmental pruning and Wallerian degeneration, using explants of embryonic dorsal root ganglion. Axonal integrity and function is compromised in a wide variety of neurodegenerative pathologies. Indeed, it is now clear that axonal dysfunction appears much earlier in the course of the disease than neuronal soma loss in several neurodegenerative diseases, indicating that axonal-specific processes are primarily targeted in these disorders. By obtaining pure axonal samples for analysis by molecular and biochemical techniques, this technique has the potential to shed new light into mechanisms regulating the physiology and pathophysiology of axons. This in turn will have an impact in our understanding of the processes that drive degenerative diseases of the nervous system.

This article describes a neuronal culture system that can be used to obtain large quantities of pure axonal samples for biochemical and immunocytochemical analyses. This technique will allow an improved understanding of normal axonal physiology and signaling pathways leading to neurodegeneration.

Producción y aislamiento de los axones de las neuronas sensoriales para el análisis bioquímico Usando porosos Filtros

Neuronal axons use specific mechanisms to mediate extension, maintain integrity, and induce degeneration. An appropriate balance of these events is ...

Isolation and Culture of Dissociated Sensory Neurons From Chick Embryos

Neurons are multifaceted cells that carry information essential for a variety of functions including sensation, motor movement, learning, and memory. Studying neurons in vivo can be challenging due to their complexity, their varied and dynamic environments, and technical limitations. For these reasons, studying neurons in vitro can prove beneficial to unravel the complex mysteries of neurons. The well-defined nature of cell culture models provides detailed control over environmental conditions and variables. Here we describe how to isolate, dissociate, and culture primary neurons from chick embryos. This technique is rapid, inexpensive, and generates robustly growing sensory neurons. The procedure consistently produces cultures that are highly enriched for neurons and has very few non-neuronal cells (less than 5%). Primary neurons do not adhere well to untreated glass or tissue culture plastic, therefore detailed procedures to create two distinct, well-defined laminin-containing substrata for neuronal plating are described. Cultured neurons are highly amenable to multiple cellular and molecular techniques, including co-immunoprecipitation, live cell imagining, RNAi, and immunocytochemistry. Procedures for double immunocytochemistry on these cultured neurons have been optimized and described here.

Cell culture models provide detailed control over environmental conditions and thus provide a powerful platform to elucidate numerous aspects of neuronal cell biology. We describe a rapid, inexpensive, and reliable method to isolate, dissociate, and culture sensory neurons from chick embryos. Details of substrata preparation and immunocytochemistry are also provided.

Aislamiento y cultivo de neuronas sensoriales disociadas De embriones de pollo

Neurons are multifaceted cells that carry information essential for a variety of functions including sensation, motor movement, learning, and memory. ...

Physiological Preparation of Hair Cells from the Sacculus of the American Bullfrog (Rana catesbeiana)

The study of hearing and balance rests upon insights drawn from biophysical studies of model systems. One such model, the sacculus of the American bullfrog, has become a mainstay of auditory and vestibular research. Studies of this organ have revealed how sensory cells hair can actively detect signals from the environment. Because of these studies, we now better understand the mechanical gating and localization of a hair cell&#39;s transduction channels, calcium&#39;s role in mechanical adaptation, and the identity of hair cell currents. This highly accessible organ continues to provide insight into the workings of hair cells. Here we describe the preparation of the bullfrog&#39;s sacculus for biophysical studies on its hair cells. We include the complete dissection procedure and provide specific protocols for the preparation of the sacculus in specific contexts. We additionally include representative results using this preparation, including the calculation of a hair bundle&#39;s instantaneous force-displacement relation and measurement of a bundle&#39;s spontaneous oscillation.

Physiological Preparation of Hair Cells from the Sacculus of the American Bullfrog Rana catesbeiana

The American bullfrog&#39;s (Rana catesbeiana) sacculus permits direct examination of hair-cell physiology. Here the dissection and preparation of the bullfrog&#39;s sacculus for biophysical studies is described. We show representative experiments from these hair cells, including the calculation of a bundle&#39;s force-displacement relation and measurement of its unforced motion.

Preparación fisiológica de las células ciliadas del sáculo de la rana toro americana (<em&gt; Catesbeiana</em&gt;)

The study of hearing and balance rests upon insights drawn from biophysical studies of model systems. One such model, the sacculus of the American ...

Tracking Drosophila Larval Behavior in Response to Optogenetic Stimulation of Olfactory Neurons

The ability of insects to navigate toward odor sources is based on the activities of their first-order olfactory receptor neurons (ORNs). While a considerable amount of information has been generated regarding ORN responses to odorants, the role of specific ORNs in driving behavioral responses remains poorly understood. Complications in behavior analyses arise due to different volatilities of odorants that activate individual ORNs, multiple ORNs activated by single odorants, and the difficulty in replicating naturally observed temporal variations in olfactory stimuli using conventional odor-delivery methods in the laboratory. Here, we describe a protocol that analyzes Drosophila larval behavior in response to simultaneous optogenetic stimulation of its ORNs. The optogenetic technology used here allows for specificity of ORN activation and precise control of temporal patterns of ORN activation. Corresponding larval movement is tracked, digitally recorded, and analyzed using custom written software. By replacing odor stimuli with light stimuli, this method allows for a more precise control of individual ORN activation in order to study its impact on larval behavior. Our method could be further extended to study the impact of second-order projection neurons (PNs) as well as local neurons (LNs) on larval behavior. This method will thus enable a comprehensive dissection of olfactory circuit function and complement studies on how olfactory neuron activities translate in to behavior responses.

Tracking Drosophila Larval Behavior in Response to Optogenetic Stimulation of Olfactory Neurons

This protocol analyzes navigational behavior of Drosophila larva in response to simultaneous optogenetic stimulation of its olfactory neurons. Light of 630 nm wavelength is used to activate individual olfactory neurons expressing a red-shifted channel rhodopsin. Larval movement is simultaneously tracked, digitally recorded, and analyzed using custom-written software.

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