Este trabajo fue financiado por los Institutos Canadienses de Investigación en Salud (CIHR) subvención a ASJK fue parcialmente apoyado por una beca de la Universidad Laval. AS es el receptor de una Cátedra de investigación de Canadá en la neurogénesis postnatal.

<ol>
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J., Bordey, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=GABA+release+and+uptake+regulate+neuronal+precursor+migration+in+the+postnatal+subventricular+zone.">GABA release and uptake regulate neuronal precursor migration in the postnatal subventricular zone.</a> J. Neurosci. 24, 7623-7631 (2004).</li><li>Martini, F. J., Valdeolmillos, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Actomyosin+contraction+at+the+cell+rear+drives+nuclear+translocation+in+migrating+cortical+interneurons.">Actomyosin contraction at the cell rear drives nuclear translocation in migrating cortical interneurons.</a> J. Neurosci. 30, 8660-8670 (2010).</li><li>Murase, S., Horwitz, A. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deleted+in+colorectal+carcinoma+and+differentially+expressed+integrins+mediate+the+directional+migration+of+neural+precursors+in+the+rostral+migratory+stream.">Deleted in colorectal carcinoma and differentially expressed integrins mediate the directional migration of neural precursors in the rostral migratory stream.</a> J. Neurosci. 22, 3568-3579 (2002).</li><li>Wilcock, A. C., Swedlow, J. R., Storey, K. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mitotic+spindle+orientation+distinguishes+stem+cell+and+terminal+modes+of+neuron+production+in+the+early+spinal+cord.">Mitotic spindle orientation distinguishes stem cell and terminal modes of neuron production in the early spinal cord.</a> Development. 134, 1943-1954 (2007).</li><li>Ono, M., Yanagawa, Y., Koyano, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=GABAergic+neurons+in+inferior+colliculus+of+the+GAD67-GFP+knock-in+mouse:+electrophysiological+and+morphological+properties.">GABAergic neurons in inferior colliculus of the GAD67-GFP knock-in mouse: electrophysiological and morphological properties.</a> Neurosci. Res. 51, 475-492 (2005).</li><li>Bozoyan, L., Khlghatyan, J., Saghatelyan, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Astrocytes+Control+the+Development+of+the+Migration-Promoting+Vasculature+Scaffold+in+the+Postnatal+Brain+via+VEGF+Signaling.">Astrocytes Control the Development of the Migration-Promoting Vasculature Scaffold in the Postnatal Brain via VEGF Signaling.</a> J. Neurosci. 32, 1687-1704 (2012).</li><li>Bovetti, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blood+vessels+form+a+scaffold+for+neuroblast+migration+in+the+adult+olfactory+bulb.">Blood vessels form a scaffold for neuroblast migration in the adult olfactory bulb.</a> J. Neurosci. 27, 5976-5980 (2007).</li><li>Platel, J. C., Heintz, T., Young, S., Gordon, V., Bordey, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tonic+activation+of+GLUK5+kainate+receptors+decreases+neuroblast+migration+in+whole-mounts+of+the+subventricular+zone.">Tonic activation of GLUK5 kainate receptors decreases neuroblast migration in whole-mounts of the subventricular zone.</a> J. Physiol. 586, 3783-3793 (2008).</li><li>Nam, S. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamic+features+of+postnatal+subventricular+zone+cell+motility:+a+two-photon+time-lapse+study.">Dynamic features of postnatal subventricular zone cell motility: a two-photon time-lapse study.</a> J. Comp. Neurol. 505, 190-208 (2007).</li><li>Kim, Y., Comte, I., Szabo, G., Hockberger, P., Szele, F. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adult+mouse+subventricular+zone+stem+and+progenitor+cells+are+sessile+and+epidermal+growth+factor+receptor+negatively+regulates+neuroblast+migration.">Adult mouse subventricular zone stem and progenitor cells are sessile and epidermal growth factor receptor negatively regulates neuroblast migration.</a> PLoS One. 4, e8122 (2009).</li><li>Bortone, D., Polleux, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=KCC2+expression+promotes+the+termination+of+cortical+interneuron+migration+in+a+voltage-sensitive+calcium-dependent+manner.">KCC2 expression promotes the termination of cortical interneuron migration in a voltage-sensitive calcium-dependent manner.</a> Neuron. 62, 53-71 (2009).</li><li>Comte, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Galectin-3+maintains+cell+motility+from+the+subventricular+zone+to+the+olfactory+bulb.">Galectin-3 maintains cell motility from the subventricular zone to the olfactory bulb.</a> J. Cell Sci. 124, 2438-2447 (2011).</li></ol>

No hay conflictos de interés declarado.

La orientación correcta de los precursores neuronales a las regiones cerebrales apropiadas es un proceso fundamental que subyace en el correcto montaje y funcionamiento de los circuitos neuronales. La gran mayoría de las células migran durante el desarrollo embrionario y en el cerebro postnatal sólo en unas pocas regiones, tales como la circunvolución OB, dentado y el cerebelo, el desplazamiento neuronal todavía tiene lugar. Los mecanismos de orquestar la migración de células en el cerebro postnatal siguen siend...

<table border="1"><tbody><tr><td> Nombre del reactivo </td><td> Empresa </td><td> Número de catálogo </td></tr><tr><td> Sacarosa </td><td> Sigma </td><td> S9378 </td></tr><tr><td> La glucosa (ACSF) </td><td> EMD </td><td> DX0145-3 </td></tr><tr><td> NaCl </td><td> Sigma </td><td> S9625 </td></tr><tr><td> KCI </td><td> Sigma </td><td> P9541 </td></tr><tr><td> MgCl 2 x6H 2 O </td><td> Sigma-Aldrich </td><td> M2670 </td></tr><tr><td> NaHCO 3 </td><td> Sigma </td><td> S5761 </td></tr><tr><td> NaH 2 PO 4 xH 2 O </td><td> EMD </td><td> SX0710-1 </td></tr><tr><td> CaCl 2 x2H 2 O </td><td> Sigma-Aldrich </td><td> C3881 </td></tr><tr><td> Dextran TexasRed </td><td> Invitrogen </td><td> D1864 </td></tr><tr><td> Dextran CascadeBlue </td><td> Invitrogen </td><td> D1976 </td></tr><tr><td> Glucosa (solución 40X) </td><td> Sigma </td><td> G8769 </td></tr><tr><td> Sodio pyruvat </td><td> Gibco </td><td> 11360-070 </td></tr><tr><td> HEPES </td><td> Sigma </td><td> H3375 </td></tr><tr><td> HBSS </td><td> Gibco </td><td> 14170-112 </td></tr><tr><td> DNasa I </td><td> Sigma </td><td> D-5025 </td></tr><tr><td> Tripsina-EDTA </td><td> Gibco </td><td> 25300-054 </td></tr><tr><td> Medio Neurobasal </td><td> Gibco </td><td> 21103-049 </td></tr><tr><td> BSA </td><td> EMD </td><td> 2930 </td></tr><tr><td> Pen / Strep </td><td> Life Technologies </td><td> 15140-122 </td></tr><tr><td> La ketamina / xilazina </td><td> CDMV </td><td> 5230 </td></tr><tr><td> Pipeta Pasteur </td><td> VWR </td><td> 14672-380 </td></tr><tr><td> Tubo cónico de 15 ml </td><td&gt; Sarstedt </td><td> 62.553.205 </td></tr><tr><td> Tubo cónico de 50 ml </td><td> Sarstedt </td><td> 62.547.205 </td></tr><tr><td> Capilares de vidrio (inyección estereotáxica) </td><td> WPI </td><td> 4878 </td></tr><tr><td> Queroseno </td><td> EMD </td><td> PX0045-3 </td></tr><tr><td> Proviodine </td><td> Rougier </td><td> 65655-1370 </td></tr><tr><td> Suture </td><td> Stoelting </td><td> 50487 </td></tr><tr><td> Anafen </td><td> CDMV </td><td> 11508 </td></tr><tr><td> Jeringa 20 cc </td><td> VWR </td><td> SS-20L2 </td></tr><tr><td> Placa de Petri </td><td> VWR </td><td> 25384-094 </td></tr><tr><td> Agar </td><td> Laboratoire Mat </td><td> AP-0108 </td></tr><tr><td> Pegamento </td><td> Permabond </td><td> 910 </td></tr><tr><td> 95% O 2/5% CO 2 </td><td> Linde </td><td> 24068835 </td></tr><tr><td> Hoja &lt;/ Td&gt; <td> WPI </td><td> 501901 </td></tr><tr><td> Nylon con malla </td><td> Warner Instruments </td><td> 64-0198 </td></tr><tr><td> Centrífugo </td><td> Eppendorf </td><td> 5702 000.019 </td></tr><tr><td> Pipetear extractor </td><td> Sutter Instrument </td><td> P-97 </td></tr><tr><td> Nanolitros inyector </td><td> WPI </td><td> B203MC4 </td></tr><tr><td> Aparato de inyección estereotáxica </td><td> WPI </td><td> 502900 </td></tr><tr><td> Sistema de perforación Micro </td><td> WPI </td><td> 501819 </td></tr><tr><td> Vibratome </td><td> Thermo Scientific </td><td> 920110 </td></tr><tr><td> Wide-field microscopio fluorescente </td><td> Olimpo </td><td> BX61WIF </td></tr><tr><td> CCD cámara </td><td> Fotometría </td><td> CS-HQ2-D </td></tr><tr><td> Ultra-quiet imágenes de cámara </td><td> Harvard Apparatus </td><td> 64-1487 </td></tr><tr><td> PH-1Serie 20 calentador plataforma </td><td> Harvard Apparatus </td><td> 64-0284 </td></tr><tr><td> Sistema de calefacción </td><td> Warner Instruments </td><td> TC-344B </td></tr><tr><td> 40X objetivo de inmersión en agua </td><td> Olimpo </td><td> 1-UM587 </td></tr><tr><td> 10X objetivo de inmersión en agua </td><td> Olimpo </td><td> 1-UM583 </td></tr><tr><td> Lambda DG-4 </td><td> Sutter Instruments </td><td> DG-4/OF </td></tr><tr><td> MetaMorph software </td><td> Molecular Devices </td><td> 40000 </td></tr><tr><td> Imaris software </td><td> Bitplane </td><td> BPI-IM70-F1 </td></tr></tbody></table>

time-lapse imaging of neuroblast migration in acute slices of the adult mouse forebrain

Existe un importante cuerpo de evidencia que indica que las nuevas neuronas funcionales están constitutivamente generado a partir de un pool endógeno de las células madre neuronales en áreas restringidas del cerebro de los mamíferos adultos. Neuroblastos recién nacidos de la zona subventricular (SVZ) migran a lo largo de la corriente migratoria rostral (RMS) hasta su destino final en el bulbo olfatorio (OB) 1. En el RMS, los neuroblastos migran tangencialmente en las cadenas de envainado por procesos astrocíticos 2,3 utilizando los vasos sanguíneos como soporte estructural y una fuente de factores moleculares necesarios para la migración 4,5. En el OB, los neuroblastos desprenderse de las cadenas y migran radialmente en las diferentes capas bulbares donde se diferencian en interneuronas e integrar en la red existente 1, 6. En este manuscrito se describe el procedimiento para la migración de células de vigilancia en rodajas agudas del cerebro de roedores. El uso de las rebanadas de agudos permite que la assessment de la migración de células en el microambiente que se parece mucho a las condiciones in vivo y en regiones del cerebro que son difíciles de acceder para imágenes in vivo. Además, se evita la condición de cultivo de largo como en el caso de cultivos de células organotípicos y que eventualmente pueden alterar las propiedades de migración de las células. Precursores neuronales en rodajas agudas se pueden visualizar utilizando la óptica DIC o proteínas fluorescentes. Etiquetado viral de precursores neuronales en la SVZ, injerto de neuroblastos reportero ratones en la SVZ de ratones de tipo salvaje, y el uso de ratones transgénicos que expresan la proteína fluorescente en neuroblastos son todos los métodos adecuados para la visualización de los neuroblastos y después de su migración. El método más tarde, sin embargo, no permite que las células individuales para ser rastreados por largos períodos de tiempo debido a la alta densidad de células marcadas. Se utilizó un microscopio de campo amplio fluorescente vertical equipado con una cámara CCD para conseguir un intervalo de adquisición relativamente rápida (una image cada 15 segundos o 30) para identificar de forma fiable el estacionaria y fases migratorias. Una identificación precisa de la duración de las fases estacionarias y migratorias es crucial para la interpretación inequívoca de los resultados. También se realizó varias adquisiciones z a paso para controlar la migración de los neuroblastos en 3D. De gran campo de imagen fluorescente se ha utilizado ampliamente para visualizar la migración neuronal 7-10. A continuación, se describe el protocolo detallado para el etiquetado de los neuroblastos, la realización de vídeo en tiempo real de imágenes de la migración neuroblast en rodajas agudas del cerebro anterior ratón adulto, y el análisis de la migración celular. Si bien el protocolo descrito ejemplifica la migración de neuroblastos en el RMS de adultos, que también se puede utilizar para seguir la migración de células en los cerebros embrionarios y posnatales temprana.

Watch this Scientific Journal Video about Time-lapse Imaging of Neuroblast Migration in Acute Slices of the Adult Mouse Forebrain at JoVE.com

Time-lapse Imaging of Neuroblast Migration in Acute Slices of the Adult Mouse Forebrain

Se describe un protocolo en tiempo real videoimaging de la migración neuronal en el cerebro anterior del ratón. La migración de viralmente marcados o injertado precursores neuronales se registró en rebanadas agudas en vivo utilizando de gran campo de imagen fluorescente con un intervalo de adquisición relativamente rápido para estudiar las diferentes fases de la migración de células, incluyendo las duraciones de las fases estacionaria y la migración y la velocidad de migración.

Time-lapse de imágenes de Migración neuroblasto en rodajas agudas del cerebro anterior ratón adulto

There is a substantial body of evidence indicating that new functional neurons are constitutively generated from an endogenous pool of neural stem cells ...

time-lapse-imaging-neuroblast-migration-acute-slices-adult-mouse

Research

JoVE Journal

Neuroscience

14.8K vistas.  Centre de Recherche Université Laval Robert-Giffard. Se describe un protocolo en tiempo real videoimaging de la migración neuronal en el cerebro anterior del ratón. La migración de viralmente marcados o injertado precursores neuronales se registró en rebanadas agudas en vivo utilizando de gran campo de imagen fluorescente con un intervalo de adquisición relativamente rápido para estudiar las diferentes fases de la migración de células, incluyendo las duraciones de las fases estacionaria y la migración y la velocida...

Video: Time-lapse Imaging of Neuroblast Migration in Acute Slices of the Adult Mouse Forebrain

An Organotypic Slice Assay for High-Resolution Time-Lapse Imaging of Neuronal Migration in the Postnatal Brain

Neurogenesis in the postnatal brain depends on maintenance of three biological events: proliferation of progenitor cells, migration of neuroblasts, as well as differentiation and integration of new neurons into existing neural circuits. For postnatal neurogenesis in the olfactory bulbs, these events are segregated within three anatomically distinct domains: proliferation largely occurs in the subependymal zone (SEZ) of the lateral ventricles, migrating neuroblasts traverse through the rostral migratory stream (RMS), and new neurons differentiate and integrate within the olfactory bulbs (OB). The three domains serve as ideal platforms to study the cellular, molecular, and physiological mechanisms that regulate each of the biological events distinctly. This paper describes an organotypic slice assay optimized for postnatal brain tissue, in which the extracellular conditions closely mimic the in vivo environment for migrating neuroblasts. We show that our assay provides for uniform, oriented, and speedy movement of neuroblasts within the RMS. This assay will be highly suitable for the study of cell autonomous and non-autonomous regulation of neuronal migration by utilizing cross-transplantation approaches from mice on different genetic backgrounds.

This protocol describes an organotypic slice assay optimized for the postnatal brain and high-resolution time-lapse imaging of neuroblast migration in the rostral migratory stream.

Un ensayo Cortar organotípicos de alta resolución de imágenes a intervalos de tiempo de la migración neuronal en el cerebro postnatal

Neurogenesis in the postnatal brain depends on maintenance of three biological events: proliferation of progenitor cells, migration of neuroblasts, as ...

Investigación

Neurociencias

Time-lapse Live Imaging of Clonally Related Neural Progenitor Cells in the Developing Zebrafish Forebrain

Precise patterns of division, migration and differentiation of neural progenitor cells are crucial for proper brain development and function1,2. To understand the behavior of neural progenitor cells in the complex in vivo environment, time-lapse live imaging of neural progenitor cells in an intact brain is critically required. In this video, we exploit the unique features of zebrafish embryos to visualize the development of forebrain neural progenitor cells in vivo. We use electroporation to genetically and sparsely label individual neural progenitor cells. Briefly, DNA constructs coding for fluorescent markers were injected into the forebrain ventricle of 22 hours post fertilization (hpf) zebrafish embryos and electric pulses were delivered immediately. Six hours later, the electroporated zebrafish embryos were mounted with low melting point agarose in glass bottom culture dishes. Fluorescently labeled neural progenitor cells were then imaged for 36hours with fixed intervals under a confocal microscope using water dipping objective lens. The present method provides a way to gain insights into the in vivo development of forebrain neural progenitor cells and can be applied to other parts of the central nervous system of the zebrafish embryo.

The present video demonstrates a method which takes advantage of the combination of electroporation and confocal microscopy to perform live imaging on individual neural progenitor cells in the developing zebrafish forebrain. In vivo analysis of the development of forebrain neural progenitor cells at a clonal level can be achieved in this way.

Time-lapse de imágenes en vivo de la relación clonal con células progenitoras neurales en el cerebro anterior El desarrollo de pez cebra

Precise patterns of division, migration and differentiation of neural progenitor cells are crucial for proper brain development and function1,2. To ...

Preparation of Acute Subventricular Zone Slices for Calcium Imaging

The subventricular zone (SVZ) is one of the two neurogenic zones in the postnatal brain. The SVZ contains densely packed cells, including neural progenitor cells with astrocytic features (called SVZ astrocytes), neuroblasts, and intermediate progenitor cells. Neuroblasts born in the SVZ tangentially migrate a great distance to the olfactory bulb, where they differentiate into interneurons. Intercellular signaling through adhesion molecules and diffusible signals play important roles in controlling neurogenesis. Many of these signals trigger intercellular calcium activity that transmits information inside and between cells. Calcium activity is thus reflective of the activity of extracellular signals and is an optimal way to understand functional intercellular signaling among SVZ cells.
Calcium activity has been studied in many other regions and cell types, including mature astrocytes and neurons. However, the traditional method to load cells with calcium indicator dye (i.e. bath loading) was not efficient at loading all SVZ cell types. Indeed, the cellular density in the SVZ precludes dye diffusion inside the tissue. In addition, preparing sagittal slices will better preserve the three-dimensional arrangement of SVZ cells, particularly the stream of neuroblast migration on the rostral-caudal axis.
Here, we describe methods to prepare sagittal sections containing the SVZ, the loading of SVZ cells with calcium indicator dye, and the acquisition of calcium activity with time-lapse movies. We used Fluo-4 AM dye for loading SVZ astrocytes using pressure application inside the tissue. Calcium activity was recorded using a scanning confocal microscope allowing a precise resolution for distinguishing individual cells. Our approach is applicable to other neurogenic zones including the adult hippocampal subgranular zone and embryonic neurogenic zones. In addition, other types of dyes can be applied using the described method.

A method to load subventricular zone (SVZ) cells with calcium indicator dyes for recording calcium activity is described. The postnatal SVZ contains tightly packed cells including neural progenitor cells and neuroblasts. Rather than using bath loading we injected the dye by pressure inside the tissue allowing better dye diffusion.

Preparación de agudos Slices zona subventricular for Imaging Calcio

The subventricular zone (SVZ) is one of the two neurogenic zones in the postnatal brain. The SVZ contains densely packed cells, including neural ...

Dual Electrophysiological Recordings of Synaptically-evoked Astroglial and Neuronal Responses in Acute Hippocampal Slices

Astrocytes form together with neurons tripartite synapses, where they integrate and modulate neuronal activity. Indeed, astrocytes sense neuronal inputs through activation of their ion channels and neurotransmitter receptors, and process information in part through activity-dependent release of gliotransmitters. Furthermore, astrocytes constitute the main uptake system for glutamate, contribute to potassium spatial buffering, as well as to GABA clearance. These cells therefore constantly monitor synaptic activity, and are thereby sensitive indicators for alterations in synaptically-released glutamate, GABA and extracellular potassium levels. Additionally, alterations in astroglial uptake activity or buffering capacity can have severe effects on neuronal functions, and might be overlooked when characterizing physiopathological situations or knockout mice. Dual recording of neuronal and astroglial activities is therefore an important method to study alterations in synaptic strength associated to concomitant changes in astroglial uptake and buffering capacities. Here we describe how to prepare hippocampal slices, how to identify stratum radiatum astrocytes, and how to record simultaneously neuronal and astroglial electrophysiological responses. Furthermore, we describe how to isolate pharmacologically the synaptically-evoked astroglial currents.

The preparation of acute brain slices from isolated hippocampi, as well as the simultaneous electrophysiological recordings of astrocytes and neurons in stratum radiatum during stimulation of schaffer collaterals is described. The pharmacological isolation of astroglial potassium and glutamate transporter currents is demonstrated.

Dos registros electrofisiológicos de sinápticamente respuestas evocadas neuronal y astroglial en agudas rodajas de hipocampo

Astrocytes form together with neurons tripartite synapses, where they integrate and modulate neuronal activity. Indeed, astrocytes sense neuronal inputs ...

In vivo Postnatal Electroporation and Time-lapse Imaging of Neuroblast Migration in Mouse Acute Brain Slices

The subventricular zone (SVZ) is one of the main neurogenic niches in the postnatal brain. Here, neural progenitors proliferate and give rise to neuroblasts able to move along the rostral migratory stream (RMS) towards the olfactory bulb (OB). This long-distance migration is required for the subsequent maturation of newborn neurons in the OB, but the molecular mechanisms regulating this process are still unclear. Investigating the signaling pathways controlling neuroblast motility may not only help understand a fundamental step in neurogenesis, but also have therapeutic regenerative potential, given the ability of these neuroblasts to target brain sites affected by injury, stroke, or degeneration.
In this manuscript we describe a detailed protocol for in vivo postnatal electroporation and subsequent time-lapse imaging of neuroblast migration in the mouse RMS. Postnatal electroporation can efficiently transfect SVZ progenitor cells, which in turn generate neuroblasts migrating along the RMS. Using confocal spinning disk time-lapse microscopy on acute brain slice cultures, neuroblast migration can be monitored in an environment closely resembling the in vivo condition. Moreover, neuroblast motility can be tracked and quantitatively analyzed. As an example, we describe how to use in vivo postnatal electroporation of a GFP-expressing plasmid to label and visualize neuroblasts migrating along the RMS. Electroporation of shRNA or CRE recombinase-expressing plasmids in conditional knockout mice employing the LoxP system can also be used to target genes of interest. Pharmacological manipulation of acute brain slice cultures can be performed to investigate the role of different signaling molecules in neuroblast migration. By coupling in vivo electroporation with time-lapse imaging, we hope to understand the molecular mechanisms controlling neuroblast motility and contribute to the development of novel approaches to promote brain repair.

In vivo Postnatal Electroporation and Time-lapse Imaging of Neuroblast Migration in Mouse Acute Brain Slices

Neuroblast migration is a fundamental event in postnatal neurogenesis. We describe a protocol for efficient labeling of neuroblasts by in vivo postnatal electroporation and subsequent visualization of their migration using time-lapse imaging of acute brain slices. We include a description for the quantitative analysis of neuroblast dynamics by video tracking.

In vivo Postnatal electroporación y time-lapse de Neuroblast Migración en rodajas de cerebro de ratón aguda

The subventricular zone (SVZ) is one of the main neurogenic niches in the postnatal brain. Here, neural progenitors proliferate and give rise to ...

Nucleofection of Rodent Neuroblasts to Study Neuroblast Migration In vitro

The subventricular zone (SVZ) located in the lateral wall of the lateral ventricles plays a fundamental role in adult neurogenesis. In this restricted area of the brain, neural stem cells proliferate and constantly generate neuroblasts that migrate tangentially in chains along the rostral migratory stream (RMS) to reach the olfactory bulb (OB). Once in the OB, neuroblasts switch to radial migration and then differentiate into mature neurons able to incorporate into the preexisting neuronal network. Proper neuroblast migration is a fundamental step in neurogenesis, ensuring the correct functional maturation of newborn neurons. Given the ability of SVZ-derived neuroblasts to target injured areas in the brain, investigating the intracellular mechanisms underlying their motility will not only enhance the understanding of neurogenesis but may also promote the development of neuroregenerative strategies.
This manuscript describes a detailed protocol for the transfection of primary rodent RMS postnatal neuroblasts and the analysis of their motility using a 3D in vitro migration assay recapitulating their mode of migration observed in vivo. Both rat and mouse neuroblasts can be quickly and efficiently transfected via nucleofection with either plasmid DNA, small hairpin (sh)RNA or short interfering (si)RNA oligos targeting genes of interest. To analyze migration, nucleofected cells are reaggregated in &#39;hanging drops&#39; and subsequently embedded in a three-dimensional matrix. Nucleofection per se does not significantly impair the migration of neuroblasts. Pharmacological treatment of nucleofected and reaggregated neuroblasts can also be performed to study the role of signaling pathways involved in neuroblast migration.

Nucleofection of Rodent Neuroblasts to Study Neuroblast Migration In vitro

Neuroblast migration is a crucial step in postnatal neurogenesis. The protocol described here can be used to investigate the role of candidate regulators of neuroblast migration by employing DNA/small hairpin RNA (shRNA) nucleofection and a 3D migration assay with neuroblasts isolated from the rodent postnatal rostral migratory stream.

Nucleofection de roedores neuroblastos para el Estudio de la Migración Neuroblast<em&gt; In vitro</em

The subventricular zone (SVZ) located in the lateral wall of the lateral ventricles plays a fundamental role in adult neurogenesis. In this restricted ...

Long-term Time Lapse Imaging of Mouse Cochlear Explants

Here we present a method for long-term time-lapse imaging of live embryonic mouse cochlear explants. The developmental program responsible for building the highly ordered, complex structure of the mammalian cochlea proceeds for around ten days. In order to study changes in gene expression over this period and their response to pharmaceutical or genetic manipulation, long-term imaging is necessary. Previously, live imaging has typically been limited by the viability of explanted tissue in a humidified chamber atop a standard microscope. Difficulty in maintaining optimal conditions for culture growth with regard to humidity and temperature has placed limits on the length of imaging experiments. A microscope integrated into a modified tissue culture incubator provides an excellent environment for long term-live imaging. In this method we demonstrate how to establish embryonic mouse cochlear explants and how to use an incubator microscope to conduct time lapse imaging using both bright field and fluorescent microscopy to examine the behavior of a typical embryonic day (E) 13 cochlear explant and Sox2, a marker of the prosensory cells of the cochlea, over 5 days.

Live imaging of the embryonic mammalian cochlea is challenging because the developmental processes at hand operate on a temporal gradient over ten days. Here we present a method for culturing and then imaging embryonic cochlear explant tissue taken from a fluorescent reporter mouse over five days.

A largo plazo Lapso de tiempo de imágenes de Ratón cocleares explantes

Here we present a method for long-term time-lapse imaging of live embryonic mouse cochlear explants. The developmental program responsible for building ...

In-depth Physiological Analysis of Defined Cell Populations in Acute Tissue Slices of the Mouse Vomeronasal Organ

In most mammals, the vomeronasal organ (VNO) is a chemosensory structure that detects both hetero- and conspecific social cues. Vomeronasal sensory neurons (VSNs) express a specific type of G protein-coupled receptor (GPCR) from at least three different chemoreceptor gene families allowing sensitive and specific detection of chemosensory cues. These families comprise the V1r and V2r gene families as well as the formyl peptide receptor (FPR)-related sequence (Fpr-rs) family of putative chemoreceptor genes. In order to understand the physiology of vomeronasal receptor-ligand interactions and downstream signaling, it is essential to identify the biophysical properties inherent to each specific class of VSNs.
The physiological approach described here allows identification and in-depth analysis of a defined population of sensory neurons using a transgenic mouse line (Fpr-rs3-i-Venus). The use of this protocol, however, is not restricted to this specific line and thus can easily be extended to other genetically modified lines or wild type animals.

Here, we describe a physiological approach that allows identification and in-depth analysis of a defined population of sensory neurons in acute coronal tissue slices of the mouse vomeronasal organ using whole-cell patch-clamp recordings.

Análisis fisiológico en profundidad de poblaciones de células definidas en el infarto agudo del tejido Rebanadas del ratón órgano vomeronasal

In most mammals, the vomeronasal organ (VNO) is a chemosensory structure that detects both hetero- and conspecific social cues. Vomeronasal sensory ...

Time-lapse Confocal Imaging of Migrating Neurons in Organotypic Slice Culture of Embryonic Mouse Brain Using In Utero Electroporation

In utero electroporation is a rapid and powerful approach to study the process of radial migration in the cerebral cortex of developing mouse embryos. It has helped to describe the different steps of radial migration and characterize the molecular mechanisms controlling this process. To directly and dynamically analyze migrating neurons they have to be traced over time. This protocol describes a workflow that combines in utero electroporation with organotypic slice culture and time-lapse confocal imaging, which allows for a direct examination and dynamic analysis of radially migrating cortical neurons. Furthermore, detailed characterization of migrating neurons, such as migration speed, speed profiles, as well as radial orientation changes, is possible. The method can easily be adapted to perform functional analyses of genes of interest in radially migrating cortical neurons by loss and gain of function as well as rescue experiments. Time-lapse imaging of migrating neurons is a state-of-the-art technique that once established is a potent tool to study the development of the cerebral cortex in mouse models of neuronal migration disorders.

Time-lapse Confocal Imaging of Migrating Neurons in Organotypic Slice Culture of Embryonic Mouse Brain Using In Utero Electroporation

This protocol provides instructions for direct observation of radially migrating cortical neurons. In utero electroporation, organotypic slice culture, and time-lapse confocal imaging are combined to directly and dynamically study the effects of overexpression or downregulation of genes of interest in migrating neurons and to analyze their differentiation during development.

Time-lapse Imágenes confocales de las neuronas migratorias en la cultura organotípica en rebanadas de cerebro de ratón embrionario<em&gt; En Utero</em&gt; Electroporación

In utero electroporation is a rapid and powerful approach to study the process of radial migration in the cerebral cortex of developing mouse embryos. It ...

Measurement of Oxygen Consumption Rate in Acute Striatal Slices from Adult Mice

Mitochondria play an important role in cellular ATP production, reactive oxygen species regulation, and Ca2+ concentration control. Mitochondrial dysfunction has been implicated in the pathogenesis of multiple neurodegenerative diseases, including Parkinson&#39;s disease (PD), Huntington&#39;s disease, and Alzheimer&#39;s disease. To study the role of mitochondria in models of these diseases, we can measure mitochondrial respiration via oxygen consumption rate (OCR) as a proxy for mitochondrial function. OCR has already been successfully measured in cell cultures, as well as isolated mitochondria. However, these techniques are less physiologically relevant than measuring OCR in acute brain slices. To overcome this limitation, the authors developed a new method using a Seahorse XF analyzer to directly measure the OCR in acute striatal slices from adult mice. The technique is optimized with a focus on the striatum, a brain area involved in PD and Huntington&#39;s disease. The analyzer performs a live cell assay using a 24-well plate, which allows the simultaneous kinetic measurement of 24 samples. The method uses circular-punched pieces of striatal brain slices as samples. We demonstrate the effectiveness of this technique by identifying a lower basal OCR in striatal slices of a mouse model of PD. This method will be of broad interest to researchers working in the field of PD and Huntington&#39;s disease.

Oxygen consumption rate (OCR) is a common proxy for mitochondrial function and can be used to study different disease models. We developed a new method using a Seahorse XF analyzer to directly measure the OCR in acute striatal slices from adult mice that is more physiologically relevant than other methods.