Name: single-cell resolution fluorescence live imaging of drosophila circadian clocks in larval brain culture
Uploaded: 2018-01-19T15:00:00
Description: Watch this Scientific Journal Video about Single-cell Resolution Fluorescence Live Imaging of Drosophila Circadian Clocks in Larval Brain Culture at JoVE.com

We thank Michael Rosbash for his mentorship and support during the initial phase of the development of this method. This work was funded by the JST PRESTO program, the Swiss National Science Foundation (31003A_149893 and 31003A_169548), the European Research Council (ERC-StG-311194), Novartis Foundation for Medical-Biomedical Research (13A39) and the University of Geneva.

1. Preparation of Stock Solutions Under a Culture Hood
<ol>
	<li>Prepare 400 mL of 1x Schneider Active Medium (SAM) optimized for ex vivo culture of larval brains (modified from reference24,25) (Table 1). Aliquot to 5 mL and flash freeze in liquid nitrogen (LN2), store at - 80 &#176;C.</li>
	<li>Prepare 1x Dissecting Saline Solution (DSS) by diluting 10x stock solution (modified from reference26) (<st...

<ol>
	<li>Sheeba, V., Kaneko, M., Sharma, V. K., Holmes, T. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Drosophila+circadian+pacemaker+circuit:+Pas+De+Deux+or+Tarantella?.">The Drosophila circadian pacemaker circuit: Pas De Deux or Tarantella?.</a> Crit Rev Biochem Mol Biol. 43 (1), 37-61 (2008).</li><li>Granados-Fuentes, D., Herzog, E. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+clock+shop:+coupled+circadian+oscillators.">The clock shop: coupled circadian oscillators.</a> Exp Neurol. 243, 21-27 (2013).</li><li>Zhang, Y., Emery, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chapter+15+-+Molecular+and+neural+control+of+insects+circadian+rhythms.">Chapter 15 - Molecular and neural control of insects circadian rhythms.</a> Insect molecular biology and biochemistry. , 513-551 (2012).</li><li>Hardin, P. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+genetic+analysis+of+circadian+timekeeping+in+Drosophila.">Molecular genetic analysis of circadian timekeeping in Drosophila.</a> Adv Genet. 74, 141-173 (2011).</li><li>Yoshii, T., Rieger, D., Helfrich-Forster, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two+clocks+in+the+brain:+an+update+of+the+morning+and+evening+oscillator+model+in+Drosophila.">Two clocks in the brain: an update of the morning and evening oscillator model in Drosophila.</a> Prog Brain Res. 199, 59-82 (2012).</li><li>Malpel, S., Klarsfeld, A., Rouyer, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circadian+synchronization+and+rhythmicity+in+larval+photoperception-defective+mutants+of+Drosophila.">Circadian synchronization and rhythmicity in larval photoperception-defective mutants of Drosophila.</a> J Biol Rhythms. 19 (1), 10-21 (2004).</li><li>Mazzoni, E. O., Desplan, C., Blau, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circadian+pacemaker+neurons+transmit+and+modulate+visual+information+to+control+a+rapid+behavioral+response.">Circadian pacemaker neurons transmit and modulate visual information to control a rapid behavioral response.</a> Neuron. 45 (2), 293-300 (2005).</li><li>Sabado, V., Vienne, L., Nunes, J. M., Rosbash, M., Nagoshi, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluorescence+circadian+imaging+reveals+a+PDF-dependent+transcriptional+regulation+of+the+Drosophila+molecular+clock.">Fluorescence circadian imaging reveals a PDF-dependent transcriptional regulation of the Drosophila molecular clock.</a> Sci Rep. 7, 41560 (2017).</li><li>Hyun, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drosophila+GPCR+Han+is+a+receptor+for+the+circadian+clock+neuropeptide+PDF.">Drosophila GPCR Han is a receptor for the circadian clock neuropeptide PDF.</a> Neuron. 48 (2), 267-278 (2005).</li><li>Lear, B. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+G+protein-coupled+receptor,+groom-of-PDF,+is+required+for+PDF+neuron+action+in+circadian+behavior.">A G protein-coupled receptor, groom-of-PDF, is required for PDF neuron action in circadian behavior.</a> Neuron. 48 (2), 221-227 (2005).</li><li>Mertens, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=PDF+receptor+signaling+in+Drosophila+contributes+to+both+circadian+and+geotactic+behaviors.">PDF receptor signaling in Drosophila contributes to both circadian and geotactic behaviors.</a> Neuron. 48 (2), 213-219 (2005).</li><li>Ayaz, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Axonal+injury+and+regeneration+in+the+adult+brain+of+Drosophila.">Axonal injury and regeneration in the adult brain of Drosophila.</a> J Neurosci. 28 (23), 6010-6021 (2008).</li><li>Prithviraj, R., Trunova, S., Giniger, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ex+vivo+culturing+of+whole,+developing+Drosophila+brains.">Ex vivo culturing of whole, developing Drosophila brains.</a> J Vis Exp. 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Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Live+imaging+of+neuroblast+lineages+within+intact+larval+brains+in+Drosophila.">Live imaging of neuroblast lineages within intact larval brains in Drosophila.</a> Cold Spring Harb Protoc. 2013 (10), 970-977 (2013).</li><li>Januschke, J., Gonzalez, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+interphase+microtubule+aster+is+a+determinant+of+asymmetric+division+orientation+in+Drosophila+neuroblasts.">The interphase microtubule aster is a determinant of asymmetric division orientation in Drosophila neuroblasts.</a> The Journal of Cell Biology. 188 (5), 693-706 (2010).</li><li>Williamson, W. R., Hiesinger, P. 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T., Currie, J., Menaker, M., Wijnen, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluorescence/luminescence+circadian+imaging+of+complex+tissues+at+single-cell+resolution.">Fluorescence/luminescence circadian imaging of complex tissues at single-cell resolution.</a> J Biol Rhythms. 25 (3), 228-232 (2010).</li><li>Liang, X., Holy, T. E., Taghert, P. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synchronous+Drosophila+circadian+pacemakers+display+nonsynchronous+Ca(2)(+)+rhythms+in+vivo.">Synchronous Drosophila circadian pacemakers display nonsynchronous Ca(2)(+) rhythms in vivo.</a> Science. 351 (6276), 976-981 (2016).</li><li>Liang, X., Holy, T. E., Taghert, P. 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A., Campusano, J. M., Su, H., O'Dowd, D. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drosophila+mushroom+body+Kenyon+cells+generate+spontaneous+calcium+transients+mediated+by+PLTX-sensitive+calcium+channels.">Drosophila mushroom body Kenyon cells generate spontaneous calcium transients mediated by PLTX-sensitive calcium channels.</a> J Neurophysiol. 94 (1), 491-500 (2005).</li><li>Hafer, N., Schedl, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dissection+of+larval+CNS+in+Drosophila+melanogaster.">Dissection of larval CNS in Drosophila melanogaster.</a> J Vis Exp. 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Here we described the method for long-term fluorescence time-lapse microscopy of cultured larval brains. The success of this type of experiments depends on multiple factors, such as the health of the culture, method for immobilization of the brain explant, fluorescence intensity and signal-to-noise ratio of the reporter, temporal and spatial resolution, and accessibility to the explant. These factors can be mutually exclusive. For example, increasing time-lapse frequency affects the health of the culture, and the immobil...

Circadian clocks help organisms to adapt to the periodic environmental changes generated by the 24 h rotation of the Earth. The interlocked transcriptional-translational feedback loops commonly underlie the molecular machinery of circadian clocks across species1. The circadian pacemaker circuit composed of clock-containing neurons integrates time-of-day information conveyed by the environmental cues, such as light/dark (LD) and temperature cycles, to orchestrate the rhythms of a plethora of daily physiological and behavioral processes2,3. The coordination of molecular rhythms with neuronal inputs and outputs is critically important for the operation of the circadian circuit but remains only partially understood.
In Drosophila, at the core of the molecular clock, the CLOCK/CYCLE (CLK/CYC) heterodimer activates the transcription of period (per) and timeless (tim). PER and TIM form a complex and enter the nucleus, where they inhibit transcriptional activity of CLK/CYC and consequently their own transcription. Post-transcriptional and post-translational regulations cause delays between CLK/CYC-mediated transcription and repression by PER/TIM, ensuring the generation of circa 24-h molecular oscillations1,3,4. About 150 neurons containing these molecular clocks form a circuit to control circadian behavior of adult flies5. A much simpler yet fully functional circadian circuit consisting of 3 groups of clock neurons - 5 ventral Lateral Neurons (LNvs; 4 PDF-positive LNvs and one PDF-negative LNv, see below), 2 Dorsal Neuron 1s (DN1s) and 2 Dorsal Neuron 2s (DN2s) - is present in the larval brain6,7.
The simple larval circadian circuit offers an excellent model to study the interactions between inter-neuronal communication and the molecular clockwork. Using our newly developed fluorescent reporter PER-TDT, which mimics the levels of PER protein and its subcellular location, we sought to characterize the dynamics of the molecular clockwork in different clock neuron subgroups in the larval circadian circuit8. Furthermore, knowing the key role of the neuropeptide pigment-dispersing factor (PDF) produced by 4 LNvs in regulating circadian rhythms at the neuronal level9,10,11, we wanted to examine the direct effect of PDF on the molecular clocks. To this end, we developed a method to monitor circadian gene expression rhythms in larval brain explant over multiple days by time-lapse confocal microscopy. The protocol was also adapted for pharmacological assays to test the effect of PDF or other compounds on the level of PER-TDT. Thus, the adaptation consists of making the brain explant culture accessible to drug application, increasing temporal resolution and imaging for a shorter duration.
Ex vivo culture of Drosophila brains of different developmental stages have been previously established12,13,14,15,16,17,18. Whereas these protocols have been used for imaging various biological phenomena, some of them are not compatible with imaging at single-cell resolution or do not support the culture for more than several hours. Alternative methods to perform long-term live imaging of circadian neurons in Drosophila include bioluminescence imaging of molecular rhythms19,20,21 and fluorescence imaging of calcium indicator with light sheet microscopy22,23. Although bioluminescence imaging can achieve higher temporal resolution and light sheet microscopy can be adaptable for in vivo imaging, they are limited on the spatial resolution and require specialized microscope systems.
The method described here is tailored to visualize fluorescent signals in the whole brain culture at single-cell resolution over multiple days. This facile and versatile method could be adapted to image cultured adult fly brains and for pharmacological experiments to study many different problems in Drosophila neurobiology.

<table>
	<tbody>
		<tr>
			<td>KH2PO4</td>
			<td>Sigma-Aldrich</td>
			<td>P5655</td>
			<td>I am not sure they are exactly the same ones we have in the lab. I chose &#34;suitable for insect cell culture&#34; whenever available</td>
		</tr>
		<tr>
			<td>CaCl2</td>
			<td>Sigma-Aldrich</td>
			<td>C7902</td>
			<td></td>
		</tr>
		<tr>
			<td>MgSO4.7H2O</td>
			<td>Sigma-Aldrich</td>
			<td>230391</td>
			<td></td>
		</tr>
		<tr>
			<td>NaCl</td>
			<td>Sigma-Aldrich</td>
			<td>S5886</td>
			<td></td>
		</tr>
		<tr>
			<td>NaHCO3</td>
			<td>Sigma-Aldrich</td>
			<td>S5761</td>
			<td></td>
		</tr>
		<tr>
			<td>D-(+) Glucose</td>
			<td>Sigma-Aldrich</td>
			<td>G7021</td>
			<td></td>
		</tr>
		<tr>
			<td>Yeast extract</td>
			<td>Sigma-Aldrich</td>
			<td>Y1000</td>
			<td></td>
		</tr>
		<tr>
			<td>Insulin</td>
			<td>Sigma-Aldrich</td>
			<td>I0516-5ML</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin-Streptomycin</td>
			<td>Sigma-Aldrich</td>
			<td>P4333</td>
			<td></td>
		</tr>
		<tr>
			<td>BIS-TRIS</td>
			<td>Sigma-Aldrich</td>
			<td>B4429</td>
			<td></td>
		</tr>
		<tr>
			<td>L-(&#8722;)-Malic acid</td>
			<td>Sigma-Aldrich</td>
			<td>M7397</td>
			<td></td>
		</tr>
		<tr>
			<td>D-(+)-Trehalose dihydrate</td>
			<td>Sigma-Aldrich</td>
			<td>T0167</td>
			<td></td>
		</tr>
		<tr>
			<td>Succinic acid</td>
			<td>Sigma-Aldrich</td>
			<td>S9512</td>
			<td></td>
		</tr>
		<tr>
			<td>Fumaric acid</td>
			<td>Sigma-Aldrich</td>
			<td>F8509</td>
			<td></td>
		</tr>
		<tr>
			<td>&#945;-Ketoglutaric acid</td>
			<td>Sigma-Aldrich</td>
			<td>K1128</td>
			<td></td>
		</tr>
		<tr>
			<td>Non-heat-inactivated, Foetal Calf Serum (FCS) Mycoplasma and Virus screened</td>
			<td>BioConcept Ltd. Amimed</td>
			<td>2-01F30-I</td>
			<td></td>
		</tr>
		<tr>
			<td>HEPES-KOH, pH 7.4</td>
			<td>E&#38;K Scientific Products</td>
			<td>EK-654011</td>
			<td></td>
		</tr>
		<tr>
			<td>KCl</td>
			<td>Sigma-Aldrich</td>
			<td>P5405</td>
			<td></td>
		</tr>
		<tr>
			<td>NaH2PO4</td>
			<td>Sigma-Aldrich</td>
			<td>S5011</td>
			<td></td>
		</tr>
		<tr>
			<td>Sucrose</td>
			<td>Sigma-Aldrich</td>
			<td>S7903</td>
			<td></td>
		</tr>
		<tr>
			<td>Fibrinogen from bovine plasma</td>
			<td>Calbiochem (Merck)</td>
			<td>341573-1GM</td>
			<td>CAUTION: Harmful by inhalation, in contact with skin and if swallowed. Manipulate under laminar flow</td>
		</tr>
		<tr>
			<td>Thrombin from bovine plasma</td>
			<td>Sigma-Aldrich</td>
			<td>T9549</td>
			<td>CAUTION: Health Hazard, use gloves</td>
		</tr>
		<tr>
			<td>PDF, NH2-NSELINSLLSLPKNMNDA-OH</td>
			<td>Chi Scientific</td>
			<td>custom made</td>
			<td></td>
		</tr>
		<tr>
			<td>Vaccum grease</td>
			<td>Sigma-Aldrich</td>
			<td>18405</td>
			<td></td>
		</tr>
		<tr>
			<td>35 mm Dish, No. 1.5 Coverslip, 20 mm Glass Diameter, Uncoated</td>
			<td>MatTek</td>
			<td>P35G-1.5-20-C</td>
			<td></td>
		</tr>
		<tr>
			<td>Corning Falcon Easy-Grip Tissue Culture Dishes</td>
			<td>fisherscientific</td>
			<td>08-772A</td>
			<td></td>
		</tr>
		<tr>
			<td>Sterile 500 mL Steritop-GP 33 mm threaded bottle top filter, 0.22 &#956;m</td>
			<td>Millipore</td>
			<td>SCGPS05RE</td>
			<td></td>
		</tr>
		<tr>
			<td>Polytetrafluoroethylene (PTFE) film</td>
			<td>Dupont</td>
			<td>200A Teflon FEP Film</td>
			<td></td>
		</tr>
		<tr>
			<td>Millex-HV Syringe Filter Unit, 0.45&#160;&#181;m, PVDF, 33&#160;mm, gamma sterilized</td>
			<td>Millipore</td>
			<td>SLHV033RS</td>
			<td></td>
		</tr>
		<tr>
			<td>Millex-GV Syringe Filter Unit, 0.22&#160;&#181;m, PVDF, 33&#160;mm, gamma sterilized</td>
			<td>Millipore</td>
			<td>SLGV033RS</td>
			<td></td>
		</tr>
		<tr>
			<td>Three-well glass dissection dish</td>
			<td>Any company</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Fine forceps, size 5, Dumont</td>
			<td>Fine Science Tools</td>
			<td>11254-20</td>
			<td></td>
		</tr>
		<tr>
			<td>Tandem scanner inverted TCS SP5 confocal microscope, with resonant scanner and HyD photo-multiplier detectors</td>
			<td>Leica microsystem CMS GmbH</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Temperature control chamber</td>
			<td>Life Imaging Services</td>
			<td>The CUBE &#38; BOX temperature control system, custom designed</td>
			<td></td>
		</tr>
		<tr>
			<td>Stage-top humidity controller</td>
			<td>Life Imaging Services</td>
			<td>custom made</td>
			<td></td>
		</tr>
		<tr>
			<td>Water Immersion Micro Dispenser: dispenser, extended micro-pump MP6 series and Autoimmersion Objective Controller software</td>
			<td>Leica microsystem CMS GmbH</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>SUM-stack creation and 3D correction drift plugin</td>
			<td>ImageJ software</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>10x iterative deconvolution</td>
			<td>AutoQuant and Imaris software</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

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.

Here, we show the representative results of the long-term recording of a circadian fluorescent reporter in ex vivo larval brain culture, and the live imaging results of PDF bath application on reporter expression.
Non-wandering L3 larvae expressing the molecular clock reporter PER-TDT and UAS-mCD8::YFP driven by a clock neuron driver Clk(856)-gal4 (Figure 1C) were entrained in LD. ...

Watch this Scientific Journal Video about Single-cell Resolution Fluorescence Live Imaging of Drosophila Circadian Clocks in Larval Brain Culture at JoVE.com

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.

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. ...

Research

JoVE Journal

Neuroscience

Visualization of Larval Segmental Nerves in 3rd Instar Drosophila Larval Preparations

Visualization of Larval Segmental Nerves in 3rd Instar Drosophila Larval Preparations

Drosophila melanogaster is emerging as a powerful model system for studying the development and function of the nervous system, particularly because of ...

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

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

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

A Rapid Approach to High-Resolution Fluorescence Imaging in Semi-Thick Brain Slices

A fundamental goal to both basic and clinical neuroscience is to better understand the identities, molecular makeup, and patterns of connectivity that are ...

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

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

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

Non-Laser Capture Microscopy Approach for the Microdissection of Discrete Mouse Brain Regions for Total RNA Isolation and Downstream Next-Generation Sequencing and Gene Expression Profiling

Non-Laser Capture Microscopy Approach for the Microdissection of Discrete Mouse Brain Regions for Total RNA Isolation and Downstream Next-Generation Sequencing and Gene Expression Profiling  |

As technological platforms, approaches such as next-generation sequencing, microarray, and qRT-PCR have great promise for expanding our understanding of ...

High-resolution Live Imaging of Cell Behavior in the Developing Neuroepithelium

The embryonic spinal cord consists of cycling neural progenitor cells that give rise to a large percentage of the neuronal and glial cells of the central ...

Ex vivo Live Imaging of Single Cell Divisions in Mouse Neuroepithelium

Ex vivo Live Imaging of Single Cell Divisions in Mouse Neuroepithelium

We developed a system that integrates live imaging of fluorescent markers and culturing slices of embryonic mouse neuroepithelium. We took advantage of ...

Live Imaging of Mitosis in the Developing Mouse Embryonic Cortex

Although of short duration, mitosis is a complex and dynamic multi-step process fundamental for development of organs including the brain. In the ...

Super-resolution Imaging of Neuronal Dense-core Vesicles

Detection of fluorescence provides the foundation for many widely utilized and rapidly advancing microscopy techniques employed in modern biological and ...

Live Imaging of Drosophila Larval Neuroblasts

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 ...