Name: in vivo optical calcium imaging of learning-induced synaptic plasticity in drosophila melanogaster
Uploaded: 2019-10-08T14:00:00
Description: Watch this Scientific Journal Video about In Vivo Optical Calcium Imaging of Learning-Induced Synaptic Plasticity in Drosophila melanogaster at JoVE.com

This work was supported by the German Research Council through the Collaborative Research Center SFB 889 &#34;Mechanisms of Sensory Processing&#34; and the Research Unit FOR 2705 &#34;Dissection of a Brain Circuit: Structure, Plasticity and Behavioral Function of the Drosophila Mushroom Body&#34;.

1. Transgenic fruit flies, Drosophila melanogaster
<ol>
	<li>Cross female virgin and male flies (raised at 25 &#176;C in 60% relative humidity on a 12 h light/dark cycle) carrying the desired Gal4 and UAS constructs25, respectively, to produce flies in which specific neurons of interest express a genetically encoded calcium indicator.</li>
	<li>Age the female progeny of the above cross until they are in the range of 3-6 days post-eclosion. Female flies are preferable because of their sl...

<ol>
	<li>Poo, M. M., 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=What+is+memory?+The+present+state+of+the+engram.">What is memory? The present state of the engram.</a> BMC Biology. 14, 40 (2016).</li><li>Martin, S. J., Grimwood, P. D., Morris, R. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synaptic+plasticity+and+memory:+an+evaluation+of+the+hypothesis.">Synaptic plasticity and memory: an evaluation of the hypothesis.</a> Annual Review of Neuroscience. 23, 649-711 (2000).</li><li>Takeuchi, T., Duszkiewicz, A. J., Morris, R. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+synaptic+plasticity+and+memory+hypothesis:+encoding,+storage+and+persistence.">The synaptic plasticity and memory hypothesis: encoding, storage and persistence.</a> Philosophical Transactions of the Royal Society London B: Biological Sciences. 369 (1633), (2013).</li><li>Josselyn, S. A., Frankland, P. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Memory+Allocation:+Mechanisms+and+Function.">Memory Allocation: Mechanisms and Function.</a> Annual Review of Neuroscience. 41, 389-413 (2018).</li><li>Chiang, A. 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=Three-dimensional+reconstruction+of+brain-wide+wiring+networks+in+Drosophila+at+single-cell+resolution.">Three-dimensional reconstruction of brain-wide wiring networks in Drosophila at single-cell resolution.</a> Current Biology. 21 (1), 1-11 (2011).</li><li>Quinn, W. G., Harris, W. A., Benzer, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Conditioned+behavior+in+Drosophila+melanogaster.">Conditioned behavior in Drosophila melanogaster.</a> Proceedings of the National Academy of Sciences of the United States of America. 71 (3), 708-712 (1974).</li><li>Heisenberg, M., Borst, A., Wagner, S., Byers, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drosophila+mushroom+body+mutants+are+deficient+in+olfactory+learning.">Drosophila mushroom body mutants are deficient in olfactory learning.</a> Journal of Neurogenetics. 2 (1), 1-30 (1985).</li><li>de Belle, J. S., Heisenberg, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Associative+odor+learning+in+Drosophila+abolished+by+chemical+ablation+of+mushroom+bodies.">Associative odor learning in Drosophila abolished by chemical ablation of mushroom bodies.</a> Science. 263 (5147), 692-695 (1994).</li><li>Gerber, B., Tanimoto, H., Heisenberg, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+engram+found?+Evaluating+the+evidence+from+fruit+flies.">An engram found? Evaluating the evidence from fruit flies.</a> Current Opinion in Neurobiology. 14 (6), 737-744 (2004).</li><li>Fiala, A., Riemensperger, T., editors, e. d. i. t. i. o. n. .. ,. R. .. M. e. n. z. e. l. a. n. d. J. .. H. .. B. y. r. n. e. ,. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Localization+of+a+memory+trace:+aversive+associative+olfactory+learning+and+short-term+memory+in+Drosophila.">Localization of a memory trace: aversive associative olfactory learning and short-term memory in Drosophila.</a> In: Learning and Memory: A Comprehensive Reference. 1, 475-482 (2017).</li><li>Cognigni, P., Felsenberg, J., Waddell, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Do+the+right+thing:+neural+network+mechanisms+of+memory+formation,+expression+and+update+in+Drosophila.">Do the right thing: neural network mechanisms of memory formation, expression and update in Drosophila.</a> Current Opinion in Neurobiology. 49, 51-58 (2018).</li><li>Hige, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=What+can+tiny+mushrooms+in+fruit+flies+tell+us+about+learning+and+memory.">What can tiny mushrooms in fruit flies tell us about learning and memory.</a> Neuroscience Research. 129, 8-16 (2018).</li><li>Aso, Y., Gr&#252;bel, K., Busch, S., Friedrich, A. B., Siwanowicz, I., Tanimoto, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+mushroom+body+of+adult+Drosophila+characterized+by+GAL4+drivers.">The mushroom body of adult Drosophila characterized by GAL4 drivers.</a> Journal of Neurogenetics. 23 (1-2), 156-172 (2009).</li><li>Pech, U., Pooryasin, A., Birman, S., Fiala, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Localization+of+the+contacts+between+Kenyon+cells+and+aminergic+neurons+in+the+Drosophila+melanogaster+brain+using+SplitGFP+reconstitution.">Localization of the contacts between Kenyon cells and aminergic neurons in the Drosophila melanogaster brain using SplitGFP reconstitution.</a> Journal of Comparative Neurology. 521 (17), 3992-4026 (2013).</li><li>Aso, Y., 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=The+neuronal+architecture+of+the+mushroom+body+provides+a+logic+for+associative+learning.">The neuronal architecture of the mushroom body provides a logic for associative learning.</a> Elife. 3, (2014).</li><li>Aso, Y., 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=Mushroom+body+output+neurons+encode+valence+and+guide+memory-based+action+selection+in+Drosophila.">Mushroom body output neurons encode valence and guide memory-based action selection in Drosophila.</a> Elife. 3, (2014).</li><li>Riemensperger, T., V&#246;ller, T., Stock, P., Buchner, E., Fiala, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Punishment+prediction+by+dopaminergic+neurons+in+Drosophila.">Punishment prediction by dopaminergic neurons in Drosophila.</a> Current Biology. 15 (21), 1953-1960 (2005).</li><li>Venken, K. J., Simpson, J. H., Bellen, H. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+manipulation+of+genes+and+cells+in+the+nervous+system+of+the+fruit+fly.">Genetic manipulation of genes and cells in the nervous system of the fruit fly.</a> Neuron. 72 (2), 202-230 (2011).</li><li>Riemensperger, T., Pech, U., Dipt, S., Fiala, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optical+calcium+imaging+in+the+nervous+system+of+Drosophila+melanogaster.">Optical calcium imaging in the nervous system of Drosophila melanogaster.</a> Biochimica et Biophysica Acta. 1820 (8), 1169-1178 (2012).</li><li>Pech, U., Revelo, N. H., Seitz, K. J., Rizzoli, S. O., Fiala, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optical+dissection+of+experience-dependent+pre-+and+postsynaptic+plasticity+in+the+Drosophila+brain.">Optical dissection of experience-dependent pre- and postsynaptic plasticity in the Drosophila brain.</a> Cell Reports. 10 (12), 2083-2095 (2015).</li><li>Tian, L., 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=Imaging+neural+activity+in+worms,+flies+and+mice+with+improved+GCaMP+calcium+indicators.">Imaging neural activity in worms, flies and mice with improved GCaMP calcium indicators.</a> Nature Methods. 6, 875-881 (2009).</li><li>Nakai, J., Ohkura, M., Imoto, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+high+signal-to-noize+Ca(2+)+probe+composed+of+a+single+green+fluorescent+protein.">A high signal-to-noize Ca(2+) probe composed of a single green fluorescent protein.</a> Nature Biotechnology. 19 (2), 137-141 (2001).</li><li>Chen, T. 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The dissection of the neural circuitry underlying learning and memory is a prominent goal in the field of neuroscience. The genetic accessibility of Drosophila and the breadth and ease of behavioral testing makes this an ideal tool to investigate such phenomena. Here, a method is presented with which it is possible to visualize, within individual flies, the modulation that occurs at a subcellular level as a result of olfactory conditioning. By carrying out both pre-training and post-training visualization of odo...

Deciphering where and how the information is acquired in the brain through learning and subsequently stored as memory constitutes one of the most challenging tasks in neuroscience1. Neuroscientific research has led to the concept of a change in synaptic transmission as the neuronal substrate that underlies learning and memory formation2,3. It is hypothesized that, during learning, synaptic connections between neuronal ensembles that are active during the perception of a stimulus become modified such that their combined activity pattern can be retrieved during memory recall, thereby instructing future behavioral action4. These &#34;engram cells&#34; and their synapses are often distributed across brain regions and levels of processing, which makes it difficult to assign observed changes in synaptic transmission to the learning of a task or a stimulus. To localize and visualize those synaptic changes that are causally linked to a specific learning task one needs an appropriate model system that allows for precisely confining those synapses.
For such an endeavor, Drosophila melanogaster is particularly suitable because it combines relative brain simplicity, behavioral richness, and experimental accessibility. Among the well-established model organisms, Drosophila is situated between the nematode C. elegans and genetically tractable mammals like mice in terms of neuronal complexity. The stereotypic number of neurons (~300) and limited behavioral repertoire is observed in C. elegans. Mammals, on the other hand, have millions of neurons and staggering behavioral complexity. The brain of the fruit fly is, with its ~100,000, neurons significantly smaller than the brains of most vertebrates, and many of the neurons are individually identifiable5. Yet, Drosophila demonstrate a broad spectrum of complex behaviors, including an ability to exhibit robust associative olfactory learning and memory formation, first described over 40 years ago6. In the course of this classical conditioning procedure, groups of flies are subjected to an odor as the conditioned stimulus (CS+) while they receive a punishing electric shock as the unconditioned stimulus (US). A second odor (CS-) is then presented without any punishment. Thereby, the animals learn to avoid the odor associated with the punishment, which can be tested in a subsequent choice situation between the two odors, CS+ and CS-. Work on dissecting the neuronal substrate underlying this behavior in Drosophila has identified the mushroom bodies (MB) as the primary site of the &#34;engram&#34;7,8,9,10 and, therefore, the circuitry of this brain region was and is the subject of intense research in order to uncover the logic by which a memory engram is acquired and stored (recently reviewed in11,12).
The Drosophila MB consists of ~2,000 intrinsic neurons (Kenyon cells) per hemisphere, organized in parallel axonal projections13. Axons of olfactory projection neurons are extended to the lateral protocerebra and to the MB calyces, the main dendritic input site of the MB and receive olfactory input from antennal lobes. The long, parallel axons bundle of Kenyon cells constitute the peduncle and the lobes. Most Kenyon cells bifurcate forming horizontal &#946;/&#946;&#39;-lobes by extending one collateral towards the midline of the brain, and the vertical &#945;/&#945;&#39;-lobes by extending second collateral projecting in the dorsal-anterior direction. The other group of Kenyon cells forms the horizontal &#947;-lobes13 of the MB where the learning process and subsequent short-term memory formation could be localized10. The MB lobes receive afferent input and provide efferent output, both of which are typically restricted to distinct compartmental sub-regions along the Kenyon cell axons14,15,16. In particular, afferent dopaminergic MB input neurons have been shown to mediate value-based, e.g., punitive, reinforcing effects in associative olfactory learning15,17. Stereotypic and individually identifiable efferent MB output neurons from the mushroom body lobes integrate information across large numbers of Kenyon cells, target diverse brain areas and bear behavior-instructive appetitive or aversive information15. This neuronal architecture has led to a concept of the organization of the associative engram. Odors are relatively precisely encoded by sparsely activated ensembles of Kenyon cells. The coincident activity of these Kenyon cell ensembles and release of dopamine - evoked by punishing stimuli - modulates transmission from Kenyon cell presynapses onto MB output neurons such that the animals will subsequently avoid this particular smell10,12. We use this rather precisely defined and localized engram as a paradigmatic case to illustrate how these learning-dependent changes in synaptic activity can be determined and monitored.
The value of Drosophila as a model system relies strongly on the unmatched genetic toolbox that allows one to express transgenes for identifying, monitoring, and controlling single neurons within complex circuits18. The advent of techniques for neuronal activity monitoring - such as calcium imaging, discussed here - have allowed for the determination of neuronal activity patterns in response to a specific stimulus. By combining specific Gal4-driven expression of genetically encoded calcium indicators (GECIs) with olfactory stimulation, one can visualize the odor-evoked calcium dynamics of neurons of interest19. In this protocol, it is shown that by further coupling this technique with a classical conditioning paradigm, it is possible to examine these olfactory responses in the context of learning. Learning-induced plasticity can be further dissected using GECIs that are not only localized to a single specific neuron, but also to specific subcompartments of a neuron. Pech et al.20 established a selection of tools that allow exactly this. By targeting GCaMP321 to either the pre- or postsynapse - via linkage to the vertebrate Synaptophysin or dHomer, respectively20- the differential modulation of these sites can be distinguished. This localization confers, in this context, an advantage over most GECIs that are ubiquitously present throughout the cytosol - e.g., GCaMP22, GCaMP321, or GCaMP623 - because it means that pre- and postsynaptic transients can be distinguished from the overall integrated calcium influx that occurs as a result of neuron activation. This can provide clues about the location and types of plasticity that occur as a result of or that cause learning and memory formation. As an example, the protocol provided here shows the value of this tool in deciphering the modulation of MB output neurons during olfactory associative learning by targeting the expression of the calcium sensor to only the postsynapse. By monitoring, within an individual fly, odor-evoked activity before and after olfactory conditioning a direct comparison can be drawn between a na&#239;ve odor response and a learned odor response. Whilst fixed in the same imaging chamber, flies are exposed to a selection of odors. Then, they receive an aversive associative conditioning protocol in which one of these odors is paired with electric shock (becoming the CS+) and another odor is presented without reinforcement (becoming the CS-). Finally, the flies are again exposed to the same odors as in the first step. Calcium dynamics are observed using two-photon microscopy.

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		<tr>
			<td>1-Octen-3-ol</td>
			<td>Sigma-Aldrich, St. Louis, MO, USA</td>
			<td>O5284</td>
			<td>Chemical used as odorant</td>
		</tr>
		<tr>
			<td>3-Octanol</td>
			<td>Sigma-Aldrich, St. Louis, MO, USA</td>
			<td>218405</td>
			<td>Chemical used as odorant</td>
		</tr>
		<tr>
			<td>4-Methylcyclohexanol</td>
			<td>Sigma-Aldrich, St. Louis, MO, USA</td>
			<td>153095</td>
			<td>Chemical used as odorant</td>
		</tr>
		<tr>
			<td>Bandpass filter for EGFP (525/50 nm)</td>
			<td>Carl Zeiss Microscopy GmbH, Jena, Germany</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Clear adhesive tape</td>
			<td>Tesa SE, Norderstedt, Germany</td>
			<td></td>
			<td>Standard claer adhesive tape</td>
		</tr>
		<tr>
			<td>Concave-convex jaws</td>
			<td>Fine Science Tools, North Vancouver, Canada</td>
			<td>10053-09</td>
			<td>Blade Holders with concave-convex jaws</td>
		</tr>
		<tr>
			<td>Fine forceps</td>
			<td>Fine Science Tools, North Vancouver, Canada</td>
			<td>11412-11</td>
			<td>Forceps with tip 0.1 x 0.06mm</td>
		</tr>
		<tr>
			<td>Hypodermic needle</td>
			<td>Sterican - B. Braun, Melsungenk, Germany</td>
			<td>4665120</td>
			<td>1.20x40mm</td>
		</tr>
		<tr>
			<td>Insect Minutien pins</td>
			<td>Fine Science Tools, North Vancouver, Canada</td>
			<td>26002-10</td>
			<td>Diameter 0.1mm, tip 0.0125mm</td>
		</tr>
		<tr>
			<td>Kentoflow</td>
			<td>Kent Express Dental Supplies, Gillingham, UK</td>
			<td>953683</td>
			<td>Blue light-curing glue</td>
		</tr>
		<tr>
			<td>Microscope slide</td>
			<td>Carl Roth GmbH &#38; Co. KG, Karlsruhe, Germany</td>
			<td>0656.1</td>
			<td>Standard objective slide 76 x 26 mm</td>
		</tr>
		<tr>
			<td>Mineral oil</td>
			<td>Sigma-Aldrich, St. Louis, MO, USA</td>
			<td>M8410</td>
			<td>Used as diluent for odorants</td>
		</tr>
		<tr>
			<td>Mode-locked Ti-Sapphire laser Chameleon Vision 2</td>
			<td>Coherent Inc., Santa Clara, CA, USA</td>
			<td></td>
			<td>Tunable infrared femtosecond laser</td>
		</tr>
		<tr>
			<td>Multiphoton Microscope LSM 7MP equipped with BiG detectors</td>
			<td>Carl Zeiss Microscopy GmbH, Jena, Germany</td>
			<td></td>
			<td>Multiphoton microscope, multiple companies provide similar devices.</td>
		</tr>
		<tr>
			<td>Plan-Apochromat 20x (NA = 1.0) water immersion objective</td>
			<td>Carl Zeiss Microscopy GmbH, Jena, Germany</td>
			<td>421452-9900-000</td>
			<td>Objective W &#34;Plan-Apochromat&#34; 20x/1.0 DIC M27 70mm</td>
		</tr>
		<tr>
			<td>Ringer&#39;s solution</td>
			<td>n.a.</td>
			<td>n.a.</td>
			<td>5mM KCl, 130mM NaCl, 2mM MgCl2, 2mM CaCl2, 5mM Hepes-NaOH, 36mM sucrose, pH = 7.4</td>
		</tr>
		<tr>
			<td>Stab knife</td>
			<td>Sharpoint, Surgical Specialties Corporation, Reading, PA, USA</td>
			<td>72-1551</td>
			<td>5.0mm Straight restricted blade depth</td>
		</tr>
		<tr>
			<td>Surgical scalpel blade</td>
			<td>Swann-Morton, Sheffield, UK</td>
			<td>0303</td>
			<td>Product No. 11</td>
		</tr>
		<tr>
			<td>Surgical scalpel handle</td>
			<td>Swann-Morton, Sheffield, UK</td>
			<td>0907</td>
			<td>Product No. 7S/S</td>
		</tr>
		<tr>
			<td>Visual Basics of Applicatons (VBA) software to receive a trigger 
			from the odor-delivery device and the electric shock 
			application device (power supply) to interact with the 
			ZEN software from Zeiss that controls the microscope.</td>
			<td>Custom-written and available upon request</td>
			<td>n.a.</td>
			<td>n.a.</td>
		</tr>
	</tbody>
</table>

in vivo optical calcium imaging of learning-induced synaptic plasticity in drosophila melanogaster

Decades of research in many model organisms have led to the current concept of synaptic plasticity underlying learning and memory formation. Learning-induced changes in synaptic transmission are often distributed across many neurons and levels of processing in the brain. Therefore, methods to visualize learning-dependent synaptic plasticity across neurons are needed. The fruit fly Drosophila melanogaster represents a particularly favorable model organism to study neuronal circuits underlying learning. The protocol presented here demonstrates a way in which the processes underlying the formation of associative olfactory memories, i.e., synaptic activity and their changes, can be monitored in vivo. Using the broad array of genetic tools available in Drosophila, it is possible to specifically express genetically encoded calcium indicators in determined cell populations and even single cells. By fixing a fly in place, and opening the head capsule, it is possible to visualize calcium dynamics in these cells whilst delivering olfactory stimuli. Additionally, we demonstrate a set-up in which the fly can be subjected, simultaneously, to electric shocks to the body. This provides a system in which flies can undergo classical olfactory conditioning - whereby a previously na&#239;ve odor is learned to be associated with electric shock punishment - at the same time as the representation of this odor (and other untrained odors) is observed in the brain via two-photon microscopy. Our lab has previously reported the generation of synaptically localized calcium sensors, which enables one to confine the fluorescent calcium signals to pre- or postsynaptic compartments. Two-photon microscopy provides a way to spatially resolve fine structures. We exemplify this by focusing on neurons integrating information from the mushroom body, a higher-order center of the insect brain. Overall, this protocol provides a method to examine the synaptic connections between neurons whose activity is modulated as a result of olfactory learning.

An example of images acquired with the above protocol can be seen in Figure 2. dHomer-GCaMP3 is expressed in an MB output neuron whose dendrites innervate the compartment 1 of the MB &#947;-lobe (the neuron is termed MVP228,29) and is genetically targeted using the split-Gal4 line MB112C16. Also, demonstrated is the difference in the subcellular localization of a cytos...

Watch this Scientific Journal Video about In Vivo Optical Calcium Imaging of Learning-Induced Synaptic Plasticity in Drosophila melanogaster at JoVE.com

In Vivo Optical Calcium Imaging of Learning-Induced Synaptic Plasticity in Drosophila melanogaster

Here we present a protocol with which pre- and/or postsynaptic calcium can be visualized in the context of Drosophila learning and memory. In vivo calcium imaging using synaptically localized calcium sensors is combined with a classical olfactory conditioning paradigm such that the synaptic plasticity underlying this type of associative learning may be determined.

In Vivo Optical Calcium Imaging of Learning-Induced Synaptic Plasticity in Drosophila melanogaster

Decades of research in many model organisms have led to the current concept of synaptic plasticity underlying learning and memory formation. ...

Research

JoVE Journal

Neuroscience

In vivo Visualization of Synaptic Vesicles Within Drosophila Larval Segmental Axons

In vivo Visualization of Synaptic Vesicles Within Drosophila Larval Segmental Axons

Elucidating the mechanisms of axonal transport has shown to be very important in determining how defects in long distance transport affect different ...

Lateral Diffusion and Exocytosis of Membrane Proteins in Cultured Neurons Assessed using Fluorescence Recovery and Fluorescence-loss Photobleaching

Membrane proteins such as receptors and ion channels undergo active trafficking in neurons, which are highly polarised and morphologically complex. This ...

In vivo Neuronal Calcium Imaging in C. elegans

In vivo Neuronal Calcium Imaging in C. elegans

The nematode worm C. elegans is an ideal model organism  for relatively simple, low cost neuronal imaging in vivo. Its small transparent body and simple, ...

In Vivo Functional Brain Imaging Approach Based on Bioluminescent Calcium Indicator GFP-aequorin

In Vivo Functional Brain Imaging Approach Based on Bioluminescent Calcium Indicator GFP-aequorin

Functional in vivo imaging has become a powerful approach to study the function and physiology of brain cells and structures of interest. Recently a new ...

Analyzing Synaptic Modulation of Drosophila melanogaster Photoreceptors after Exposure to Prolonged Light

Analyzing Synaptic Modulation of Drosophila melanogaster Photoreceptors after Exposure to Prolonged Light

The nervous system has the remarkable ability to adapt and respond to various stimuli. This neural adjustment is largely achieved through plasticity at ...

Slice Patch Clamp Technique for Analyzing Learning-Induced Plasticity

The slice patch clamp technique is a powerful tool for investigating learning-induced neural plasticity in specific brain regions. To analyze ...

Pentylenetetrazole-Induced Kindling Mouse Model

Pentylenetetrazole (PTZ) is a GABA-A receptor antagonist. An intraperitoneal injection of PTZ into an animal induces an acute, severe seizure at a high ...

Ex Vivo Calcium Imaging for Visualizing Brain Responses to Endocrine Signaling in Drosophila

Ex Vivo Calcium Imaging for Visualizing Brain Responses to Endocrine Signaling in Drosophila

Organ-to-organ communication by endocrine signaling, for example, from the periphery to the brain, is essential for maintaining homeostasis. As a model ...

3D Modeling of Dendritic Spines with Synaptic Plasticity

Computational modeling of diffusion and reaction of chemical species in a three-dimensional (3D) geometry is a fundamental method to understand the ...