Damos las gracias a Bernard Charroux para los debates. Este trabajo fue financiado por la Escuela de Biomédica ley de Kirchhoff.

1. La disección de la retina Drosophila <ol><li> Llenar una y de un portaobjetos de vidrio de 3 Bueno con tampón fosfato salino (PBS 1X), y luego vuela por anestesiar a CO 2. Tanto hombres como mujeres pueden ser utilizados para este experimento. </li><li> Una vez que las moscas son anestesiados, recoger una mosca con unas pinzas y colocarlo en el plato pequeño de PBS. </li><li> Bajo un microscopio de disección, una pizca de la trompa con pinzas, y luego separar la cabeza del cuerpo si se rompe el cuello con un segundo conjunto de pinzas. </li><li> Sosteniendo la cabeza de mosca de la trompa, cortado por la mitad a lo largo de la línea media hacia la izquierda / derecha de la cabeza de mosca con micro tijeras para revelar el cerebro. </li><li> Use una pipeta de punta de corte para recoger a la retina, y la transferencia de un segundo pozo de la lámina de vidrio de 3 llenarse bien con medio Schneider. </li><li> En primer lugar, pelar lejos la mayor parte de la cutícula de cabeza y luego retire el cerebro con una pinza. Mantener la retina situado entre la lámina y la córnea. </li><li> A continuación, la transferencia de la retina en una gota (50 l) del medio de Schnieder frescas se colocan directamente de la lámina de vidrio. </li></ol> 2. La disección de la omatidios <ol><li> Dependiendo del propósito final de la disección (ya sea de imágenes inmediata o la cultura) y en la óptica del microscopio de fluorescencia (directa o inversa), este paso puede tener lugar en un portaobjetos o en una placa de 24 pocillos. Con el propósito final de esta disección, el omatidios se diseca directamente en el portaobjetos de vidrio. </li><li> Sujete bien el extremo más dorsal o ventral de la retina con una pinza. Utilizando micro tijeras, corte la retina en la mitad a lo largo de la línea media dorsal / ventral para exponer los omatidios en el centro del ojo. </li><li> Seguir para captar la retina de tal manera que la córnea está orientada hacia abajo y la lámina hacia arriba. Utilizando una aguja de tungsteno muy bien, separar el omatidios de la lámina y la córnea. </li><li> Solo omatidios y grupos de omatidios recogerá en el fondo del pozo o la diapositiva. Elimine todos los residuos más grandes que se haya quedado antes de proceder. </li></ol> 3. Tratamiento, las manchas y de imagen <ol><li> Para el análisis de la autofagia, diluir 1:1000 LysoTracker en la caída de Schneider (primero diluir 1:10 en Schneider y luego añadir 0,5 l de la caída en la diapositiva), mezclar y esperar 10 segundos. </li><li> Retire el exceso de líquido de la diapositiva, teniendo cuidado de dejar atrás el omatidios. Esto se hace mejor con una punta fina de gel de carga. </li><li> Añadir una gota de Vectashield para cubrir los omatidios, un cubreobjetos y sellar con nailpolish. </li></ol> 4. Los resultados representativos: La buena ejecución del protocolo deben dejar un número de omatidios individuales y de pequeños grupos de omatidios mantienen unidas por fragmentos de lámina, pero bien separados en el lado de la córnea. Estas se pueden visualizar como en este ejemplo para visualizar Atg8: GFP y LysoTracker, mostrando autofagosomas, lisosomas y autophagolysosomes (Fig. 3). El método puede ser utilizado para obtener imágenes en vivo, sin embargo, en este caso es de señalar que la autofluorescencia de la media de Schneider se hace difícil distinguir las señales de baja intensidad de fluorescencia. Un problema adicional es que los gránulos de pigmento que permanecer unidos a los fotorreceptores son intensamente fluorescentes, especialmente en el canal rojo. Un cuadro campo claro puede ser necesario para distinguirlos de los orgánulos genuino. <img src="/files/ftp_upload/2882/2882fig1.jpg" alt="Figura 1"/> Figura 1. Diagrama de flujo del procedimiento de disección para obtener omatidios individuales o pequeños grupos de omatidios de la retina de la mosca. <img src="/files/ftp_upload/2882/2882fig2.jpg" alt="Figura 2"/> Figura 2. Las posibles variaciones del protocolo simple de describir aquí que involucran a la genética y el envejecimiento marcha ascendente de la disección y la tinción o cultivo para un máximo de 24 horas y posterior administración de fármacos de la disección. <img src="/files/ftp_upload/2882/2882fig3.jpg" alt="Figura 3"/> Figura 3 escaneo confocal de autofagosomas y los lisosomas en una sola omatidio disecados de aw; GMR-Gal4, UAS-Atro75QN; UAS-GFP:.: Atg8 / + volar, que expresa un mutante de poliglutamina Atrophin y de 12 días a 29 ° C. El panel de campo claro (derecha) muestra la estructura casi intacta de la omatidio y el marco indica la zona analizada. Los lisosomas marcas rojas, verdes los autofagosomas, lisosomas auto-, lo que resulta de la fusión de los dos orgánulos, aparecen de color amarillo. Las puntas de flecha indican dos eventos de fusión en curso entre los autofagosomas y los lisosomas.

<ol>
	<li>Marsh, J. L., Thompson, L. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drosophila+in+the+study+of+neurodegenerative+disease.">Drosophila in the study of neurodegenerative disease.</a> Neuron. 52, 169-178 (2006).</li><li>Mizushima, N., Levine, B., Cuervo, A. M., Klionsky, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Autophagy+fights+disease+through+cellular+self-digestion.">Autophagy fights disease through cellular self-digestion.</a> Nature. 451, 1069-1075 (2008).</li><li>Nisoli, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neurodegeneration+by+polyglutamine+Atrophin+is+not+rescued+by+induction+of+autophagy.">Neurodegeneration by polyglutamine Atrophin is not rescued by induction of autophagy.</a> Cell Death Differ. 17, 1577-1587 (2010).</li><li>Charroux, B., Fanto, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+fine+line+between+waste+disposal+and+recycling:+DRPLA+fly+models+illustrate+the+importance+of+completing+the+autophagy+cycle+for+rescuing+neurodegeneration.">The fine line between waste disposal and recycling: DRPLA fly models illustrate the importance of completing the autophagy cycle for rescuing neurodegeneration.</a> Autophagy. 6, 667-669 (2010).</li><li>Hardie, R. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Voltage-sensitive+potassium+channels+in+Drosophila+photoreceptors.">Voltage-sensitive potassium channels in Drosophila photoreceptors.</a> J Neurosci. 11, 3079-3095 (1991).</li><li>Lee, T., Luo, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mosaic+analysis+with+a+repressible+cell+marker+(MARCM)+for+Drosophila+neural+development.">Mosaic analysis with a repressible cell marker (MARCM) for Drosophila neural development.</a> Trends in neurosciences. 24, 251-254 (2001).</li><li>Xu, T., Rubin, G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+genetic+mosaics+in+developing+and+adult+Drosophila+tissues.">Analysis of genetic mosaics in developing and adult Drosophila tissues.</a> Development. 117, 1223-1237 (1993).</li><li>Gambis, A., Dourlen, P., Steller, H., Mollereau, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two-color+in+vivo+imaging+of+photoreceptor+apoptosis+and+development+in+Drosophila.">Two-color in vivo imaging of photoreceptor apoptosis and development in Drosophila.</a> Dev Biol. 351, 128-1234 (2011).</li><li>Napoletano, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polyglutamine+Atrophin+provokes+neurodegeneration+in+Drosophila+by+repressing+fat.">Polyglutamine Atrophin provokes neurodegeneration in Drosophila by repressing fat.</a> The EMBO journal. 30, 945-958 (2011).</li><li>Ravikumar, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inhibition+of+mTOR+induces+autophagy+and+reduces+toxicity+of+polyglutamine+expansions+in+fly+and+mouse+models+of+Huntington+disease.">Inhibition of mTOR induces autophagy and reduces toxicity of polyglutamine expansions in fly and mouse models of Huntington disease.</a> Nature. 36, 585-595 (2004).</li><li>Zou, S., Meadows, S., Sharp, L., 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=Genome-wide+study+of+aging+and+oxidative+stress+response+in+Drosophila+melanogaster.">Genome-wide study of aging and oxidative stress response in Drosophila melanogaster.</a> Proceedings of the National Academy of Sciences of the United States of America. 97, 13726-13731 (2000).</li></ol>

No hay conflictos de interés declarado.

La disección omatidio único que aquí se presenta permite la recolección de información de celda más profunda sobre los procesos biológicos como la neurodegeneración, cuando el modelo en el ojo de Drosophila. Las neuronas fotorreceptoras son más accesibles que otras neuronas y el citoplasma es muy grande, y por lo tanto adecuado para estudiar la dinámica de la vesícula, en las células del mismo utilizado eficientemente en muchos modelos para cuantificar la neurodegeneración en vivo. El aspe...

<table border="1"><tbody><tr><th> Nombre del reactivo </th><th> Empresa </th><th> Número de catálogo </th><th> Comentarios (opcional) </th></tr><tr><td> Dispensador de CO2 portátil </td><td> Flystuff </td><td> 59-150 </td><td> Recambios disponibles </td></tr><tr><td> Pinzas DUMONT n º 5 </td><td> AGAR Científico </td><td> T5034 </td><td></td></tr><tr><td> 3-Bueno portaobjetos de vidrio </td><td> EMS </td><td> 71561-01 </td><td></td></tr><tr><td> Micro tijeras </td><td> VWR </td><td> HAMMHSB516-09 </td><td></td></tr><tr><td> Medio de Schneider </td><td> VWR </td><td> 733-1663 </td><td></td></tr><tr><td> LysoTracker Red DND-99 </td><td> Invitrogen </td><td> L7528 </td><td></td></tr><tr><td> Superfrost Diapositivas </td><td> VWR </td><td> 631-0108 </td><td></td></tr><tr><td> Vectashield con DAPI </td><td> Vector de Laboratorios </td><td> H-1200 </td><td></td></tr><tr><td> Cubreobjetos </td><td> VWR </td><td> 631-1336 </td><td></td></tr></tbody></table>

single drosophila ommatidium dissection and imaging

La mosca de la fruta Drosophila melanogaster ha hecho valiosas contribuciones a la investigación en neurociencias y ha sido utilizado ampliamente como un modelo para las enfermedades neurodegenerativas por su poderosa genética 1. El ojo de la mosca, en particular, ha sido el órgano de elección para la investigación neurodegeneración, siendo la parte más accesible y la vida puede prescindir de la Drosophila sistema nervioso. Sin embargo, la principal advertencia de los ojos intactos, es la dificultad, debido a la intensa autofluorescencia de los pigmentos, en los eventos de formación de imágenes intracelulares, como la dinámica de la autofagia 2, que son fundamentales para la comprensión de la neurodegeneración. Recientemente, hemos utilizado la disección y la cultura de un solo omatidios 3 que ha sido esencial para nuestra comprensión de las disfunciones autofagia en un modelo de vuelo de Dentatorubro-Pallidoluysian atrofia (DRPLA) 3, 4. Ahora el informe una descripción completa de esta técnica (Fig. 1), una adaptación de los estudios electrofisiológicos 5, que es probable que se expanda enormemente la posibilidad de volar por los modelos de neurodegeneración. Este método puede ser adaptado a la imagen en vivo eventos subcelulares y para supervisar la administración de fármacos eficaces en las células fotorreceptoras (Fig. 2). Si se utiliza en combinación con las técnicas del mosaico de 6-8, las respuestas de las células genéticamente diferentes se analizaron en paralelo (Fig. 2).

Watch this Scientific Journal Video about Single Drosophila Ommatidium Dissection and Imaging at JoVE.com

Single Drosophila Ommatidium Dissection and Imaging

El factor limitante en el uso de los adultos<em&gt; Drosophila</emLos ojos&gt; para estudiar la neurodegeneración y la biología celular es la imagen difícil de procesos intracelulares. Se describe la disección de omatidios solo para generar una bona-fide cultivo primario de células neuronales, que pueden ser sometidos a un tratamiento de drogas y de imagen avanzada.

Solo Drosophila Omatidio disección e Imagen

The fruit fly Drosophila melanogaster has made invaluable contributions to neuroscience research and has been used widely as a model for neurodegenerative ...

single-drosophila-ommatidium-dissection-and-imaging

Research

JoVE Journal

Neuroscience

Single Drosophila Ommatidium Dissection and Imaging

14.0K vistas.  King's College London. El factor limitante en el uso de los adultos Drosophila para estudiar la neurodegeneración y la biología celular es la imagen difícil de procesos intracelulares. Se describe la disección de omatidios solo para generar una bona-fide cultivo primario de células neuronales, que pueden ser sometidos a un tratamiento de drogas y de imagen avanzada.

Video: Single Drosophila Ommatidium Dissection and Imaging

Single Sensillum Recordings in the Insects Drosophila melanogaster and Anopheles gambiae

The sense of smell is essential for insects to find foods, mates, predators, and oviposition sites3. Insect olfactory sensory neurons (OSNs) are enclosed in sensory hairs called sensilla, which cover the surface of olfactory organs. The surface of each sensillum is covered with tiny pores, through which odorants pass and dissolve in a fluid called sensillum lymph, which bathes the sensory dendrites of the OSNs housed in a given sensillum. The OSN dendrites express odorant receptor (OR) proteins, which in insects function as odor-gated ion channels4, 5. The interaction of odorants with ORs either increases or decreases the basal firing rate of the OSN. This neuronal activity in the form of action potentials embodies the first representation of the quality, intensity, and temporal characteristics of the odorant6, 7.
Given the easy access to these sensory hairs, it is possible to perform extracellular recordings from single OSNs by introducing a recording electrode into the sensillum lymph, while the reference electrode is placed in the lymph of the eye or body of the insect. In Drosophila, sensilla house between one and four OSNs, but each OSN typically displays a characteristic spike amplitude. Spike sorting techniques make it possible to assign spiking responses to individual OSNs. This single sensillum recording (SSR) technique monitors the difference in potential between the sensillum lymph and the reference electrode as electrical spikes that are generated by the receptor activity on OSNs1, 2, 8. Changes in the number of spikes in response to the odorant represent the cellular basis of odor coding in insects. Here, we describe the preparation method currently used in our lab to perform SSR on Drosophila melanogaster and Anopheles gambiae, and show representative traces induced by the odorants in a sensillum-specific manner.

Single Sensillum Recordings in the Insects Drosophila melanogaster and Anopheles gambiae

Electrophysiological responses of olfactory sensory neurons to odorants can be measured in insects using single sensillum recordings. In this video article we will demonstrate how to perform single sensillum recordings in the antennae of the vinegar fly (Drosophila melanogaster) and the maxillary palps of the malaria mosquito (Anopheles gambiae).

Grabaciones solo Sensillum en los insectos Drosophila melanogaster Y Anopheles gambiae</em

The sense of smell is essential for insects to find foods, mates, predators, and oviposition sites3. Insect olfactory sensory neurons (OSNs) are enclosed ...

Investigación

Neurociencias

Dissection and Imaging of Active Zones in the Drosophila Neuromuscular Junction

The Drosophila larvae neuromuscular junction (NMJ) is an excellent model for the study of synaptic structure and function. Drosophila is well known for the ease of powerful genetic manipulations and the larval nervous system has proven particularly useful in studying not only normal function but also perturbations that accompany some neurological disease (Lloyd and Taylor, 2010). Many key synaptic molecules found in Drosophila are also found in mammals and like most CNS excitatory synapses in mammals, the Drosophila NMJ is glutamatergic and demonstrates activity-dependent remodeling (Kohet al. , 2000). Additionally, Drosophila neurons can be individually identified because their innervation patterns are stereotyped and repetitive making it possible to study identified synaptic terminals, such as those between motor neurons and the body-wall muscle fibers that they innervate (Keshishian and Kim, 2004). The existence of evolutionarily conserved synapse components along with the ease of genetic and physical manipulation make the Drosophila model ideal for investigating the mechanisms underlying synaptic function (Budnik, 1996).
The active zones at synaptic terminals are of particular interest because these are the sites of neurotransmitter release. NC82 is a monoclonal antibody that recognizes the Drosophila protein Bruchpilot (Brp), a CAST1/ERC family member that is an important component of the active zone (Waghet al. , 2006). Brp was shown to directly shape the active zone T-bar and is responsible for effectively clustering Ca2+ channels beneath the T-bar density (Fouquetet al. , 2009). Mutants of Brp have reduced Ca2+ channel density, depressed evoked vesicle release, and altered short-term plasticity (Kittelet al. , 2006). Alterations to active zones have been observed in Drosophila disease models. For example, immunofluorescence using the NC82 antibody showed that the active zone density was decreased in models of amyotrophic lateral sclerosis and Pitt-Hopkins syndrome (Ratnaparkhiet al. , 2008; Zweieret al. , 2009). Thus, evaluation of active zones, or other synaptic proteins, in Drosophila larvae models of disease may provide a valuable initial clue to the presence of a synaptic defect.
Preparing whole-mount dissected Drosophila larvae for immunofluorescence analysis of the NMJ requires some skill, but can be accomplished by most scientists with a little practice. Presented is a method that provides for multiple larvae to be dissected and immunostained in the same dissection dish, limiting environmental differences between each genotype and providing sufficient animals for confidence in reproducibility and statistical analysis.

Dissection and Imaging of Active Zones in the Drosophila Neuromuscular Junction

The neuromuscular junction (NMJ) of Drosophila melanogaster is an important model system for studying normal synaptic function as well as perturbations to synaptic function found in certain neurological diseases. We present a protocol for dissection of the Drosophila larval motor system and immunostaining for active zone proteins within the NMJ.

La disección y la imagen de zonas activas en el Drosophila La unión neuromuscular

The Drosophila  larvae neuromuscular junction (NMJ) is an excellent model for the study of synaptic structure and function. Drosophila  is well known for ...

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 ...

A Single-fly Assay for Foraging Behavior in Drosophila

For many animals, hunger promotes changes in the olfactory system in a manner that facilitates the search for appropriate food sources. In this video article, we describe an automated assay to measure the effect of hunger or satiety on olfactory dependent food search behavior in the adult fruit fly Drosophila melanogaster. In a light-tight box illuminated by red light that is invisible to fruit flies, a camera linked to custom data acquisition software monitors the position of six flies simultaneously. Each fly is confined to walk in individual arenas containing a food odor at the center. The testing arenas rest on a porous floor that functions to prevent odor accumulation. Latency to locate the odor source, a metric that reflects olfactory sensitivity under different physiological states, is determined by software analysis. Here, we discuss the critical mechanics of running this behavioral paradigm and cover specific issues regarding fly loading, odor contamination, assay temperature, data quality, and statistical analysis.

A Single-fly Assay for Foraging Behavior in Drosophila

In this video article, we describe an automated assay to measure the effect of hunger or satiety on olfactory dependent food search behavior in the adult fruit fly Drosophila melanogaster.

Un ensayo de una sola mosca por el comportamiento de forrajeo en<em&gt; Drosophila</em

For many animals, hunger promotes changes in the olfactory system in a manner that facilitates the search for appropriate food sources. In this video ...

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 ...

A Simple One-step Dissection Protocol for Whole-mount Preparation of Adult Drosophila Brains

There is an increasing interest in using Drosophila to model human brain degenerative diseases, map neuronal circuitries in adult brains, and study the molecular and cellular basis of higher brain functions. A whole-mount preparation of adult brains with well-preserved morphology is critical for such whole brain-based studies, but can be technically challenging and time-consuming. This protocol describes an easy-to-learn, one-step dissection approach of an adult fly head in less than 10 s, while keeping the intact brain attached to the rest of the body to facilitate subsequent processing steps. The procedure helps remove most of the eye and tracheal tissues normally associated with the brain that can interfere with the later imaging step, and also places less demand on the quality of the dissecting forceps. Additionally, we describe a simple method that allows convenient flipping of the mounted brain samples on a coverslip, which is important for imaging both sides of the brains with similar signal intensity and quality. As an example of the protocol, we present an analysis of dopaminergic (DA) neurons in adult brains of WT (w1118) flies. The high efficacy of the dissection method makes it particularly useful for large-scale adult brain-based studies in Drosophila.

A Simple One-step Dissection Protocol for Whole-mount Preparation of Adult Drosophila Brains

The adult Drosophila brain is a valuable system for studying neuronal circuitry, higher brain functions, and complex disorders. An efficient method to dissect whole brain tissue from the small fly head will facilitate brain-based studies. Here we describe a simple, one-step dissection protocol of adult brains with well-preserved morphology.

Un simple de un solo paso para la disección Protocolo Todo el montaje Preparación de adulto<em&gt; Drosophila</emLos cerebros&gt;

There is an increasing interest in using Drosophila to model human brain degenerative diseases, map neuronal circuitries in adult brains, and study the ...

In Vivo Single-Molecule Tracking at the Drosophila Presynaptic Motor Nerve Terminal

An increasing number of super-resolution microscopy techniques are helping to uncover the mechanisms that govern the nanoscale cellular world. Single-molecule imaging is gaining momentum as it provides exceptional access to the visualization of individual molecules in living cells. Here, we describe a technique that we developed to perform single-particle tracking photo-activated localization microscopy (sptPALM) in Drosophila larvae. Synaptic communication relies on key presynaptic proteins that act by docking, priming, and promoting the fusion of neurotransmitter-containing vesicles with the plasma membrane. A range of protein-protein and protein-lipid interactions tightly regulates these processes and the presynaptic proteins therefore exhibit changes in mobility associated with each of these key events. Investigating how mobility of these proteins correlates with their physiological function in an intact live animal is essential to understanding their precise mechanism of action. Extracting protein mobility with high resolution in vivo requires overcoming limitations such as optical transparency, accessibility, and penetration depth. We describe how photoconvertible fluorescent proteins tagged to the presynaptic protein Syntaxin-1A can be visualized via slight oblique illumination and tracked at the motor nerve terminal or along the motor neuron axon of the third instar Drosophila larva.

In Vivo Single-Molecule Tracking at the Drosophila Presynaptic Motor Nerve Terminal

Here we illustrate how single molecule photo-activated localization microscopy can be carried out on the motor nerve terminal of a live Drosophila melanogaster third instar larva.

En Vivo Una sola molécula de seguimiento en la Terminal presináptica del nervio Motor del Drosophila

An increasing number of super-resolution microscopy techniques are helping to uncover the mechanisms that govern the nanoscale cellular world. ...

Single-cell Resolution Fluorescence Live Imaging of Drosophila Circadian Clocks in Larval Brain Culture

The circadian pacemaker circuit orchestrates rhythmic behavioral and physiological outputs coordinated with environmental cues, such as day/night cycles. The molecular clock within each pacemaker neuron generates circadian rhythms in gene expression, which underlie the rhythmic neuronal functions essential to the operation of the circuit. Investigation of the properties of the individual molecular oscillators in different subclasses of pacemaker neurons and their interaction with neuronal signaling yields a better understanding of the circadian pacemaker circuit. Here, we present a time-lapse fluorescent microscopy approach developed to monitor the molecular clockwork in clock neurons of cultured Drosophila larval brain. This method allows the multi-day recording of the rhythms of genetically encoded fluorescent circadian reporters at single-cell resolution. This setup can be combined with pharmacological manipulations to closely analyze real-time response of the molecular clock to various compounds. Beyond circadian rhythms, this multipurpose method in combination with powerful Drosophila genetic techniques offers the possibility to study diverse neuronal or molecular processes in live brain tissue.

Single-cell Resolution Fluorescence Live Imaging of Drosophila Circadian Clocks in Larval Brain Culture

The goal of this protocol is to establish ex vivo Drosophila larval brain culture optimized to monitor circadian molecular rhythms with long-term fluorescence time-lapse imaging. The application of this method to pharmacological assays is also discussed.

Sola célula resolución fluorescencia vivo la proyección de imagen de relojes circadianos de Drosophila en cerebro larvas cultura

The circadian pacemaker circuit orchestrates rhythmic behavioral and physiological outputs coordinated with environmental cues, such as day/night cycles. ...

Dissection of Single Skeletal Muscle Fibers for Immunofluorescent and Morphometric Analyses of Whole-Mount Neuromuscular Junctions

The neuromuscular junction (NMJ) is a specialized point of contact between the motor nerve and the skeletal muscle. This peripheral synapse exhibits high morphological and functional plasticity. In numerous nervous system disorders, NMJ is an early pathological target resulting in neurotransmission failure, weakness, atrophy, and even in muscle fiber death. Due to its relevance, the possibility to quantitatively assess certain aspects of the relationship between NMJ components can help to understand the processes associated with its assembly/disassembly. The first obstacle when working with muscles is to gain the technical expertise to quickly identify and dissect without damaging their fibers. The second challenge is to utilize high-quality detection methods to obtain NMJ images that can be used to perform quantitative analysis. This article presents a step-by-step protocol for dissecting extensor digitorum longus and soleus muscles from rats. It also explains the use of immunofluorescence to visualize pre and postsynaptic elements of whole-mount NMJs. Results obtained demonstrate that this technique can be used to establish the microscopic anatomy of the synapsis and identify subtle changes in the status of some of its components under physiological or pathological conditions.

The ability to accurately detect neuromuscular junction components is crucial in evaluating modifications in its architecture because of pathological or developmental processes. Here we present a complete description of a straightforward method to obtain high-quality images of whole-mount neuromuscular junctions that can be used to perform quantitative measurements.

Disección De Fibras Musculares Esqueléticas Individuales Para Análisis Inmunofluorescentes Y Morfométricos De Las Uniones Neuromusculares De Montaje Completo

The neuromuscular junction (NMJ) is a specialized point of contact between the motor nerve and the skeletal muscle. This peripheral synapse exhibits high ...

Monitoreo de eventos epileptiformes en Drosophila a través de imágenes de calcio

Ex Vivo Calcium Imaging for Drosophila Model of Epilepsy

Epilepsy is a neurological disorder characterized by recurrent seizures, partially correlated with genetic origin, affecting over 70 million individuals worldwide. Despite the clinical importance of epilepsy, the functional analysis of neural activity in the central nervous system is still to be developed. Recent advancements in imaging technology, in combination with stable expression of genetically encoded calcium indicators, such as GCaMP6, have revolutionized the study of epilepsy at both brain-wide and single-cell resolution levels. Drosophila melanogaster has emerged as a tool for investigating the molecular and cellular mechanisms underlying epilepsy due to its sophisticated molecular genetics and behavioral assays. In this study, we present a novel and efficient protocol for ex vivo calcium imaging in GCaMP6-expressing adult Drosophila to monitor epileptiform activities. The whole brain is prepared from cac, a well-known epilepsy gene, knockdown flies for calcium imaging with a confocal microscope to identify the neural activity as a follow-up to the bang-sensitive seizure-like behavior assay. The cac knockdown flies showed a higher rate of seizure-like behavior and abnormal calcium activities, including more large spikes and fewer small spikes than wild-type flies. The calcium activities were correlated to seizure-like behavior. This methodology serves as an efficient methodology in screening the pathogenic genes for epilepsy and exploring the potential mechanism of epilepsy at the cellular level.

Autor destacado: Perspectivas sobre las técnicas y los hallazgos de los avances recientes en la investigación de la epilepsia 

Here, we present a protocol for ex vivo calcium imaging in GCaMP6-expressing adult Drosophila to monitor epileptiform activities. The protocol provides a valuable tool for investigating ictal events in adult Drosophila through ex vivo calcium imaging, allowing for exploration of the potential mechanisms of epilepsy at the cellular levels.

Ex Vivo Imágenes de calcio para el modelo de epilepsia de Drosophila

Epilepsy is a neurological disorder characterized by recurrent seizures, partially correlated with genetic origin, affecting over 70 million individuals ...