Los autores reconocen con gratitud el trabajo de Liuliu Zheng y Zenghui Xue, que ayudaron a ser pioneros en esta técnica en el laboratorio Sokac, así como de Hasan Seede, quien ayudó con el análisis. El trabajo para este estudio está financiado por una subvención de NIH (R01 GM115111).

<ol>
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No se declaran conflictos de intereses.

La importancia de este método es que utiliza el protocolo bien establecido de microinyección en embriones de Drosophila 21,22,23,24,25,26,27 para permitir nuevas investigaciones sobre el ASR y el conjunto de barras actin acompañantes. Una ventaja importante de inyectar G-actin<su...

Este protocolo describe cómo inyectar G-actinRojo para visualizar el montaje de barras de actina intranuclear en embriones estresados por calor que están siendo sometidos a una respuesta inducible a la tensión actin (ASR)1. Desarrollamos este protocolo para ayudar a los estudios del ASR, que en embriones conduce a morfosis interrumpida y viabilidad reducida, y en adultos los tipos de células humanas se asocian con patologías como insuficiencia renal2,miopías musculares3,y la enfermedad de Alzheimer y Huntington4,5,6,7,8. Este ASR es inducido por numerosas tensiones celulares, incluyendo choque de calor9,10,11,estrés oxidativo4,6,síntesis ATP reducida12,y huntingtina anormal u oligomerización amiloide β4,5,6,7,9,13,14,15,16. Un sello distintivo del ASR es el montaje de varillas de actina aberrantes en el citoplasma o núcleo de las células afectadas, que es impulsado por la hiperactivación inducida por el estrés de una proteína que interactúa con actina, Cofilina1,5,6,10. Lamentablemente, siguen existiendo lagunas clave en el conocimiento con respecto al ASR. Por ejemplo, se desconoce la función de las varillas actin. No entendemos por qué se forman varillas en el citoplasma de algunos tipos de células, pero el núcleo de otros. Tampoco está claro si el ASR es protector o maladaptivo para las células o embriones sometidos a estrés. Por último, todavía no conocemos los mecanismos detallados subyacentes a la hiperactivación de cofilina o el conjunto de varillas actin. Por lo tanto, este protocolo proporciona un ensayo rápido y versátil para sondear el ASR visualizando la formación de varillas actin y dinámicas en el sistema experimental altamente tractable del embrión de mosca de la fruta viva.
El protocolo para microinyecto G-actinRed en embriones drosophila vivos fue desarrollado inicialmente para estudiar la dinámica de las estructuras normales de actina citoplasmática17 durante eventos de construcción de tejidos. En esos estudios, encontramos que la inyecciónroja de G-actin no afectaba negativamente a los procesos de desarrollo tempranos en el embrión, incluida la citoquinasis o la gastrulación17,18. A continuación, modificamos el protocolo, adaptando el manejo del embrión y la inyección de G-actinrojo para permitir la toma de imágenes de barras de actina en embriones estresados por calor sometidos al ASR1. Otros métodos además de la inyección de G-actinrojo se pueden utilizar para visualizar actina en embriones. Estos métodos se basan en la expresión de proteínas fluorescentes (FPs) etiquetadas para actuar o a dominios de proteínas de unión a la actina, como Utrophin-mCherry, Lifeact, F-tractin-GFP y Moesin-GFP (revisada en19). Sin embargo, el uso de estas sondas FP requiere precaución porque pueden estabilizar o interrumpir algunas estructuras de actina, no etiquetar por igual todas las estructuras de actina20, y en el caso de actin-GFP, son altamente sobreexpresados – problemático para el análisis del conjunto de varillas que no sólo depende del estrés, sino también actuar en la concentración dependiente1. Por lo tanto, G-actinRed es la sonda preferida para estudios de varilla en embriones de mosca, y el gran tamaño del embrión permite su fácil inyección.
El flujo de trabajo de este protocolo es similar a otras técnicas de microinjeción bien establecidas que se han utilizado para inyectar proteínas, ácidos nucleicos, fármacos e indicadores fluorescentes en embriones de Drosophila 21,22,23,24,25,26,27. Sin embargo, después de la microinyección de G-actinRed aquí, los embriones están expuestos a estrés por calor leve para inducir el ASR y el conjunto de varilla de actina intranuclear. Para laboratorios con acceso a moscas y un equipo de inyección, este método debe ser fácilmente implementable y adaptable para líneas de estudio específicas con respecto a la ASR, incluyendo su inducción por diferentes tensiones o modulación en distintos antecedentes genéticos.

<table><tbody><tr><td>Adenosine triphosphate (ATP)</td><td>Millipore-Sigma</td><td>A23835G</td><td>Component of G buffer</td></tr><tr><td>Apple juice, Mott&#039;s, 64 fl oz</td><td>Mott&#039;s</td><td>014800000344</td><td>Component of apple juice plates</td></tr><tr><td>Bacto Agar</td><td>BD</td><td>214010</td><td>Component of apple juice plates</td></tr><tr><td>Bleach, PureBright Germicidal, 6.0% sodium hypochlorite</td><td>KIK International</td><td>059647210020</td><td>For dechorionating embryos</td></tr><tr><td>Calcium chloride</td><td>Millipore-Sigma</td><td>C1016500G</td><td>Component of G buffer</td></tr><tr><td>Cell strainer, 70 &amp;mu;m</td><td>Falcon</td><td>352350</td><td>For collecting dechorionated embryos</td></tr><tr><td>Confocal microscope, LSM 880 34-channel with Airyscan</td><td>Zeiss</td><td>0000001994956</td><td>For imaging intranuclear actin rods</td></tr><tr><td>Desiccant</td><td>Drierite</td><td>24001</td><td>For desiccating embryos</td></tr><tr><td>Dissecting microscope, Stemi 508 Stereoscope with 8:1 zoom</td><td>Zeiss</td><td>4350649000000</td><td>For arranging embryos on agar wedge</td></tr><tr><td>Dissecting needle, 5 in</td><td>Fisher Scientific</td><td>08965A</td><td>For arranging embryos on agar wedge</td></tr><tr><td>Dithiothreitol (DTT)</td><td>Fisher Scientific</td><td>BP1725</td><td>Component of G buffer</td></tr><tr><td>Double-sided Tape, Scotch Permanent, 0.5 in x 250 in</td><td>3M</td><td>021200010323</td><td>For making embryo glue</td></tr><tr><td>Embryo collection cage</td><td>Genessee Scientific</td><td>59100</td><td>For housing adult flies and collecting embryos</td></tr><tr><td>Fine tip tweezers, Dumont Tweezer, Style 5</td><td>Electron Microscopy Sciences</td><td>72701D</td><td>For arranging embryos on agar wedge</td></tr><tr><td>Glass capillaries, Borosillicate glass, thin 1 mm x 0.75 mm</td><td>World Precision Instruments, Inc.</td><td>TW1004</td><td>For microneedles</td></tr><tr><td>Halocarbon oil 27</td><td>Millipore-Sigma</td><td>H8773100ML</td><td>For hydration of embryos</td></tr><tr><td>Heated stage incubator</td><td>Zeiss</td><td>4118579020000, 4118609020000, 4118609010000</td><td>For confocal imaging</td></tr><tr><td>Lab Tissue Wipers, KimWipes</td><td>Kimberly-Clark</td><td>34155</td><td>Lab tissue wipers</td></tr><tr><td>Light microscope, Invertoskop 40C Inverted Phase contrast microscope, refurbished</td><td>Zeiss</td><td>Discontinued</td><td>Injection microscope</td></tr><tr><td>Methyl-4-hydroxybenzoate</td><td>Millipore-Sigma</td><td>H36471KG</td><td>Component of apple juice plates</td></tr><tr><td>Microinjector, FemtoJet4x</td><td>Eppendorf</td><td>5253000025</td><td>Microinjector</td></tr><tr><td>Micro loader tips, epT.I.P.S. 20 &amp;mu;L</td><td>Eppendorf</td><td>5242956003</td><td>For loading microneedles</td></tr><tr><td>Micromanipulator and injection stage with x,y,z dials for needle adjustment</td><td>Bernard Instruments, Inc (Houston, TX)</td><td>Custom</td><td>For performing microinjections</td></tr><tr><td>Micropipette puller, Model P-97, Flaming/Brown</td><td>Sutter Instruments</td><td>P97</td><td>For pulling capillary tubes to make microneedles</td></tr><tr><td>Microscope cover glass 24x50-1.5</td><td>Fisher Scientific</td><td>12544E</td><td>For mounting embryos</td></tr><tr><td>Microscope slides, Lilac Colorfrost, Precleaned, 25 x 75 x 1mm</td><td>Fisher Scientific</td><td>22037081</td><td>For mounting embryos for injection</td></tr><tr><td>n-Heptane</td><td>Fisher Scientific</td><td>H3601</td><td>Component of embryo glue</td></tr><tr><td>Objective, 10x</td><td>Zeiss</td><td>Discontinued</td><td>10x objective for injection microscope</td></tr><tr><td>Objective, C-Apochromat 40x/1,2 W Korr. FCS</td><td>Zeiss</td><td>4217679971711</td><td>40x water objective for confocal</td></tr><tr><td>Objective, LD LCI Plan-Apochromat 25x/0.8 Imm Cor DIC M27 for oil, water, silicone oil or glycerine immersion (D=0-0.17mm) (WD=0.57mm at D=0.17mm)</td><td>Zeiss</td><td>4208529871000</td><td>25x mixed immersion objective for confocal</td></tr><tr><td>Objective, Plan-Apocrhomat 63x/1.40 Oil DIC f/ELYRA</td><td>Zeiss</td><td>4207829900799</td><td>63x oil objective for confocal</td></tr><tr><td>Paintbrush, Robert Simmons Expression E85 Pointed Round size 2</td><td>Daler-Rowney</td><td>038372016954</td><td>For transferring embryos</td></tr><tr><td>Paper towels, Kleenex C-fold paper towels, white</td><td>Kimberly-Clark</td><td>884266344845</td><td>For blotting cell strainer</td></tr><tr><td>Pasteur pipette, 5 3/4 in</td><td>Fisher Scientific</td><td>1367820A</td><td>For covering embryos with oil</td></tr><tr><td>Petri dish, glass, 100 x 20 mm</td><td>Corning</td><td>3160102</td><td>For humid incubation chamber</td></tr><tr><td>Petri dish, plastic, 60 x 15 mm</td><td>VWR</td><td>25384092</td><td>For apple juice plates</td></tr><tr><td>Pipette, Eppendorf Reference 0.5-10 &amp;mu;L</td><td>Eppendorf</td><td>2231000604</td><td>For loading the microneedle</td></tr><tr><td>Pipette tip, xTIP4 250 &amp;mu;L</td><td>Biotix</td><td>63300006</td><td>For adding embryo glue to coverslip</td></tr><tr><td>Razor blade</td><td>VWR</td><td>55411050</td><td>For cutting agar wedge, tape, pipette tips</td></tr><tr><td>Rhodamine-conjugated globular actin, human platelet (non-muscle; 4x10 &amp;mu;g)</td><td>Cytoskeleton, Inc.</td><td>APHR-A</td><td>G-actin^Red</td></tr><tr><td>Scintillation vial, 20 mL Glass borosillicate with polyethylene liner and urea caps</td><td>Fisher Scientific</td><td>033377</td><td>For making embryo glue</td></tr><tr><td>Screw top jar, 16 oz</td><td>Nalgene</td><td>000194414195</td><td>For desiccating embryos</td></tr><tr><td>Stage micrometer</td><td>Electron Microscopy Sciences</td><td>602104PG</td><td>For calibrating volume of G-actin injection</td></tr><tr><td>Sucrose</td><td>Millipore-Sigma</td><td>840971KG</td><td>Component of apple juice plates</td></tr><tr><td>Trizma base</td><td>Millipore-Sigma</td><td>T15031KG</td><td>Component of G buffer</td></tr><tr><td>Yeast, Lesaffre Yeast Corporation Yeast, Red Star Active Dry, 32 oz</td><td>Lesaffre Yeast Corporation</td><td>117929157002</td><td>Component of yeast paste</td></tr></tbody></table>

imaging intranuclear actin rods in live heat stressed drosophila embryos

El propósito de este protocolo es visualizar varillas de actina intranuclear que se ensamblan en embriones drosophila melanogaster vivos después del estrés térmico. Las barras actin son un sello distintivo de una respuesta al estrés actin (ASR) conservada e inducible que acompaña a las patologías humanas, incluida la enfermedad neurodegenerativa. Anteriormente, demostramos que el ASR contribuye a fallos de morfosis y a una menor viabilidad del desarrollo de embriones. Este protocolo permite el estudio continuo de los mecanismos subyacentes al montaje de varillas actin y el ASR en un sistema modelo que es altamente apto para la creación de imágenes, genética y bioquímica. Los embriones se recogen y montan en una cubierta para prepararlos para la inyección. La actina globulaular conjugada con rhodamina (G-actinrojo)se diluye y se carga en un microneedle. Se realiza una sola inyección en el centro de cada embrión. Después de la inyección, los embriones se incuban a temperatura elevada y las barras de actina intranuclear se visualizan mediante microscopía confocal. La recuperación de fluorescencia después de los experimentos de fotobleaching (FRAP) se puede realizar en las barras actin; y otras estructuras ricas en actina en el citoplasma también se pueden imaginar. Encontramos que G-actinRed polimeriza como G-actin endógeno y no interfiere, por sí solo, con el desarrollo normal de embriones. Una limitación de este protocolo es que se debe tener cuidado durante la inyección para evitar lesiones graves en el embrión. Sin embargo, con la práctica, inyectar G-actinrojo en embriones de Drosophila es una manera rápida y confiable de visualizar varillas de actina y se puede utilizar fácilmente con moscas de cualquier genotipo o con la introducción de otras tensiones celulares, incluyendo hipoxia y estrés oxidativo.

Un flujo de trabajo esquemático de manejo de embriones se representa en la Figura 1y se presenta un calendario para un experimento típico en la Tabla 1. Una estimación para un buen resultado experimental es que por cada 10 embriones inyectados, al menos la mitad de los embriones vistos estarán en la etapa de desarrollo correcta, sin daños, y exhibirán un ASR robusto con estrés térmico a 32 °C. Este ASR será evidenciado por el montaje de varillas de actina intranuc...

Watch this Scientific Journal Video about Imaging Intranuclear Actin Rods in Live Heat Stressed Drosophila Embryos at JoVE.com

Imaging Intranuclear Actin Rods in Live Heat Stressed Drosophila Embryos

El objetivo de este protocolo es inyectar actina globular conjugada con rhodamina en embriones de Drosophila y el conjunto de barras de actina intranuclear de imagen después del estrés térmico.

Imágenes Intranuclear Actin Rods en vivo calor estresado Drosophila Embriones

The purpose of this protocol is to visualize intranuclear actin rods that assemble in live Drosophila melanogaster embryos following heat stress. Actin ...

imaging-intranuclear-actin-rods-live-heat-stressed-drosophila

Research

JoVE Journal

Developmental Biology

Imaging Intranuclear Actin Rods in Live Heat Stressed Drosophila Embryos

3.4K vistas.  Baylor College of Medicine. El objetivo de este protocolo es inyectar actina globular conjugada con rhodamina en embriones de Drosophila y el conjunto de barras de actina intranuclear de imagen después del estrés térmico.

Video: Imaging Intranuclear Actin Rods in Live Heat Stressed Drosophila Embryos

Upright Imaging of Drosophila Egg Chambers

Drosophila melanogaster oogenesis provides an ideal context for studying varied developmental processes since the ovary is relatively simple in architecture, is well-characterized, and is amenable to genetic analysis. Each egg chamber consists of germ-line cells surrounded by a single epithelial layer of somatic follicle cells. Subsets of follicle cells undergo differentiation during specific stages to become several different cell types. Standard techniques primarily allow for a lateral view of egg chambers, and therefore a limited view of follicle cell organization and identity. The upright imaging protocol describes a mounting technique that enables a novel, vertical view of egg chambers with a standard confocal microscope. Samples are first mounted between two layers of glycerin jelly in a lateral (horizontal) position on a glass microscope slide. The jelly with encased egg chambers is then cut into blocks, transferred to a coverslip, and flipped to position egg chambers upright. Mounted egg chambers can be imaged on either an upright or an inverted confocal microscope. This technique enables the study of follicle cell specification, organization, molecular markers, and egg development with new detail and from a new perspective.

Upright Imaging of Drosophila Egg Chambers

The upright imaging method described in this protocol allows for the detailed visualization of the poles of a developing Drosophila melanogaster egg. This end-on view provides a new perspective into the arrangements and morphologies of multiple cell types in the follicular epithelium.

Imaging Upright de<em&gt; Drosophila</em&gt; Cámaras de huevo

Drosophila melanogaster oogenesis provides an ideal context for studying varied developmental processes since the ovary is relatively simple in ...

Investigación

Biología del Desarrollo

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 ...

Neurociencias

Imaging Calcium in Drosophila at Egg Activation

Egg activation is a universal process that includes a series of events to allow the fertilized egg to complete meiosis and initiate embryonic development. One aspect of egg activation, conserved across all organisms examined, is a change in the intracellular concentration of calcium (Ca2+) often termed a 'Ca2+ wave'. While the speed and number of oscillations of the Ca2+ wave varies between species, the change in intracellular Ca2+ is key in bringing about essential events for embryonic development. These changes include resumption of the cell cycle, mRNA regulation, cortical granule exocytosis, and rearrangement of the cytoskeleton.
In the mature Drosophila egg, activation occurs in the female oviduct prior to fertilization, initiating a series of Ca2+-dependent events. Here we present a protocol for imaging the Ca2+ wave in Drosophila. This approach provides a manipulable model system to interrogate the mechanism of the Ca2+ wave and the downstream changes associated with it.

Imaging Calcium in Drosophila at Egg Activation

This article describes an adaptable ex vivo protocol for visualizing Ca2+ during egg activation in Drosophila.

El calcio de imágenes en<em&gt; Drosophila</em&gt; En la activación del huevo

Egg activation is a universal process that includes a series of events to allow the fertilized egg to complete meiosis and initiate embryonic development. ...

In Vivo Imaging of Muscle-tendon Morphogenesis in Drosophila Pupae

Muscles together with tendons and the skeleton enable animals including humans to move their body parts. Muscle morphogenesis is highly conserved from animals to humans. Therefore, the powerful Drosophila model system can be used to study concepts of muscle-tendon development that can also be applied to human muscle biology. Here, we describe in detail how morphogenesis of the adult muscle-tendon system can be easily imaged in living, developing Drosophila pupae. Hence, the method allows investigating proteins, cells and tissues in their physiological environment. In addition to a step-by-step protocol with helpful tips, we provide a comprehensive overview of fluorescently tagged marker proteins that are suitable for studying the muscle-tendon system. To highlight the versatile applications of the protocol, we show example movies ranging from visualization of long-term morphogenetic events &#8211; occurring on the time scale of hours and days &#8211; to visualization of short-term dynamic processes like muscle twitching occurring on time scale of seconds. Taken together, this protocol should enable the reader to design and perform live-imaging experiments for investigating muscle-tendon morphogenesis in the intact organism.

In Vivo Imaging of Muscle-tendon Morphogenesis in Drosophila Pupae

Here, we present an easy-to-use and versatile method to perform live imaging of developmental processes in general and muscle-tendon morphogenesis in particular in living Drosophila pupae.

En Vivo Proyección de imagen del músculo-tendón morfogénesis en Drosophila pupa

Muscles together with tendons and the skeleton enable animals including humans to move their body parts. Muscle morphogenesis is highly conserved from ...

Drosophila Embryo Preparation and Microinjection for Live Cell Microscopy Performed using an Automated High Content Analyzer

Modern approaches in quantitative live cell imaging have become an essential tool for exploring cell biology, by enabling the use of statistics and computational modeling to classify and compare biological processes. Although cell culture model systems are great for high content imaging, high throughput studies of cell morphology suggest that ex vivo cultures are limited in recapitulating the morphological complexity found in cells within living organisms. As such, there is a need for a scalable high throughput model system to image living cells within an intact organism. Described here is a protocol for using a high content image analyzer to simultaneously acquire multiple time-lapse videos of embryonic Drosophila melanogaster development during the syncytial blastoderm stage. The syncytial blastoderm has traditionally served as a great in vivo model for imaging biological events; however, obtaining a significant number of experimental replicates for quantitative and high-throughput approaches has been labor intensive and limited by the imaging of a single embryo per experimental repeat. Presented here is a method to adapt imaging and microinjection approaches to suit a high content imaging system, or any inverted microscope capable of automated multipoint acquisition. This approach enables the simultaneous acquisition of 6-12 embryos, depending on desired acquisition factors, within a single imaging session.

Presented here is a protocol to microinject and simultaneously image multiple Drosophila embryos during embryonic development using a plate-based, high content imager.

Preparación y Microinyección de embriones de Drosophila para microscopía de células vivas realizada mediante un analizador automatizado de alto contenido

Modern approaches in quantitative live cell imaging have become an essential tool for exploring cell biology, by enabling the use of statistics and ...

In vivo Imaging of Intact Drosophila Larvae at Sub-cellular Resolution

Recent improvements in optical imaging, genetically encoded fluorophores and genetic tools allowing efficient establishment of desired transgenic animal lines have enabled biological processes to be studied in the context of a living, and in some instances even behaving, organism. In this protocol we will describe how to anesthetize intact Drosophila larvae, using the volatile anesthetic desflurane, to follow the development and plasticity of synaptic populations at sub-cellular resolution1-3. While other useful methods to anesthetize Drosophila melanogaster larvae have been previously described4,5,6,7,8, the protocol presented herein demonstrates significant improvements due to the following combined key features: (1) A very high degree of anesthetization; even the heart beat is arrested allowing for lateral resolution of up to 150 nm1, (2) a high survival rate of &gt; 90% per anesthetization cycle, permitting the recording of more than five time-points over a period of hours to days2 and (3) a high sensitivity enabling us in 2 instances to study the dynamics of proteins expressed at physiological levels. In detail, we were able to visualize the postsynaptic glutamate receptor subunit GluR-IIA expressed via the endogenous promoter1 in stable transgenic lines and the exon trap line FasII-GFP1. (4) In contrast to other methods4,7 the larvae can be imaged not only alive, but also intact (i.e. non-dissected) allowing observation to occur over a number of days1. The accompanying video details the function of individual parts of the in vivo imaging chamber2,3, the correct mounting of the larvae, the anesthetization procedure, how to re-identify specific positions within a larva and the safe removal of the larvae from the imaging chamber.

In vivo Imaging of Intact Drosophila Larvae at Sub-cellular Resolution

This protocol describes a reliable method for anesthetization and imaging of intact Drosophila melanogaster larvae. We have utilized the volatile anesthetic desflurane to allow for repetitive imaging at sub-cellular resolution and re-identification of structures for up to a few days1.

Imágenes in vivo de larvas de Drosophila intactos a nivel sub-celular Resolución

Recent improvements in optical imaging, genetically encoded fluorophores and genetic tools allowing efficient establishment of desired transgenic animal ...

Biología

Real-Time Imaging of Germline Stem Cells in Drosophila Ex Vivo Germaria Culture

Extended Live Imaging of Female Drosophila melanogaster Germline Stem Cell Niches

Live imaging methods allow the analysis of dynamic cellular processes in detail and in real-time. The Drosophila ovary represents an excellent model to explore the dynamics of a myriad of developmental processes, such as cell division, stemness, differentiation, migration, apoptosis, autophagy, cellular adhesion, etc., over time. Recently, we have implemented an extended ex vivo culture and live imaging of the female Drosophila GSC niche. Using a Drosophila line harboring a GFP::Par-1 transgene as an example, this method allows the visualization of the GSCs&#39; asymmetric division within their niche and the description of the changes in the spectrosome morphology along the cell cycle. Here, we present a detailed protocol for the ex vivo culture of Drosophila germaria, enabling prolonged visualization of the female GSC niche. Importantly, this protocol is broadly applicable to live imaging GSCs with multiple fluorescently tagged proteins of interest that are available in stock centers and/or in the Drosophila research community.

Here, we provide a detailed protocol to perform live imaging of the asymmetric division of germline stem cells (GSCs) in the Drosophila ovarian niche. We use a transgenic line that ubiquitously expresses a green fluorescent protein (GFP) fusion of the spectrosome protein Par-1.

Live imaging methods allow the analysis of dynamic cellular processes in detail and in real-time. The Drosophila ovary represents an excellent model to ...

Live Imaging of GFP-labeled Proteins in Drosophila Oocytes

The Drosophila oocyte has been established as a versatile system for investigating fundamental questions such as cytoskeletal function, cell organization, and organelle structure and function. The availability of various GFP-tagged proteins means that many cellular processes can be monitored in living cells over the course of minutes or hours, and using this technique, processes such as RNP transport, epithelial morphogenesis, and tissue remodeling have been described in great detail in Drosophila oocytes1,2.
The ability to perform video imaging combined with a rich repertoire of mutants allows an enormous variety of genes and processes to be examined in incredible detail. One such example is the process of ooplasmic streaming, which initiates at mid-oogenesis3,4. This vigorous movement of cytoplasmic vesicles is microtubule and kinesin-dependent5 and provides a useful system for investigating cytoskeleton function at these stages.
Here I present a protocol for time lapse imaging of living oocytes using virtually any confocal microscopy setup.

Live Imaging of GFP-labeled Proteins in Drosophila Oocytes

A protocol for live imaging of GFP-tagged proteins or autofluorescent structures in individual Drosophila oocytes is described.

Imágenes en directo de las proteínas GFP-etiquetados en<em&gt; Drosophila</em&gt; Los ovocitos

The  Drosophila oocyte has been established as a versatile system for investigating  fundamental questions such as cytoskeletal function, cell ...

Cytological Analysis of Spermatogenesis: Live and Fixed Preparations of Drosophila Testes

Drosophila melanogaster is a powerful model system that has been widely used to elucidate a variety of biological processes. For example, studies of both the female and male germ lines of Drosophila have contributed greatly to the current understanding of meiosis as well as stem cell biology. Excellent protocols are available in the literature for the isolation and imaging of Drosophila ovaries&#160;and testes3-12. Herein, methods for the dissection and preparation of Drosophila testes for microscopic analysis are described with an accompanying video demonstration. A protocol for isolating testes from the abdomen of adult males and preparing slides of live tissue for analysis by phase-contrast microscopy as well as a protocol for fixing and immunostaining testes for analysis by fluorescence microscopy are presented. These techniques can be applied in the characterization of Drosophila mutants that exhibit defects in spermatogenesis as well as in the visualization of subcellular localizations of proteins.

Cytological Analysis of Spermatogenesis: Live and Fixed Preparations of Drosophila Testes

Methods for isolating and preparing Drosophila testes samples (live and fixed) for imaging by phase-contrast and fluorescence microscopy are described herein.&#160;

Análisis citológico de espermatogénesis: Los preparativos en directo y fijas de<em&gt; Drosophila</em&gt; Testículos

Drosophila melanogaster is a powerful model system that has been widely used to elucidate a variety of biological processes. For example, studies of both ...

Visualización de redes de microtúbulos en uniones neuromusculares y células musculares de Drosophila

Using Drosophila Larval Neuromuscular Junction and Muscle Cells to Visualize Microtubule Network

The microtubule network is an essential component of the nervous system. Mutations in many microtubules regulatory proteins are associated with neurodevelopmental disorders and neurological diseases, such as microtubule-associated protein Tau to neurodegenerative diseases, microtubule severing protein Spastin and Katanin 60 cause hereditary spastic paraplegia and neurodevelopmental abnormalities, respectively. Detection of microtubule networks in neurons is advantageous for elucidating the pathogenesis of neurological disorders. However, the small size of neurons and the dense arrangement of axonal microtubule bundles make visualizing the microtubule networks challenging. In this study, we describe a method for dissection of the larval neuromuscular junction and muscle cells, as well as immunostaining of &#945;-tubulin and microtubule-associated protein Futsch to visualize microtubule networks in Drosophila melanogaster. The neuromuscular junction permits us to observe both pre-and post-synaptic microtubules, and the large size of muscle cells in Drosophila larva allows for clear visualization of the microtubule network. Here, by mutating and overexpressing Katanin 60 in Drosophila melanogaster,&#160;and then examining the microtubule networks in the neuromuscular junction and muscle cells, we&#160;accurately reveal the regulatory role of Katanin 60 in neurodevelopment. Therefore, combined with the powerful genetic tools of Drosophila&#160;melanogaster, this protocol greatly facilitates genetic screening and microtubule dynamics analysis for the role of microtubule network regulatory proteins in the nervous system.

Autor destacado: Comprensión de la red de microtúbulos en las uniones neuromusculares de Drosophila 

Here, we present a detailed protocol to visualize the microtubule networks in neuromuscular junctions and muscle cells. Combined with the powerful genetic tools of Drosophila melanogaster, this protocol greatly facilitates genetic screening and microtubule-dynamics analysis for the role of microtubule network regulatory proteins in the nervous system.

Imágenes Intranuclear Actin Rods en vivo calor estresado Drosophila Embriones

Resumen

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