Name: an antibody feeding approach to study glutamate receptor trafficking in dissociated primary hippocampal cultures
Uploaded: 2019-08-02T15:00:00
Description: Watch this Scientific Journal Video about An Antibody Feeding Approach to Study Glutamate Receptor Trafficking in Dissociated Primary Hippocampal Cultures at JoVE.com

We thank the Northwestern Center for Advanced Microscopy for the use of the Nikon A1 Confocal microscope and their assistance in planning and analyzing the experiments. This research was supported by NIGMS (T32GM008061) (A. M. C.), and NIA (R00AG041225) and a NARSAD Young Investigator Grant from the Brain &#38; Behavior Research Foundation (#24133) (A. S. -C.).

Work pertaining to hippocampal primary culture preparation was reviewed and approved by the Northwestern University Animal Care and Use Committee (protocol #IS00001151).
1. Preparation Before Labeling
<ol>
	<li>Preparation and maintenance of primary hippocampal cultures
	<ol>
		<li>Prepare primary hippocampal cultures at a density of 150,000 cells plated on poly-D-lysine-coated (0.1 mg/mL) 18 mm cover glasses. Excellent guides for dissociated neuronal culture preparation are...

<ol>
	<li>Enns, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Overview+of+protein+trafficking+in+the+secretory+and+endocytic+pathways.">Overview of protein trafficking in the secretory and endocytic pathways.</a> Current Protocols in Cell Biology. , (2001).</li><li>Bedford, F. K., Binder, M. D., Hirokawa, N., Windhorst, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Encyclopedia of Neuroscience. , 3385-3389 (2009).</li><li>Diering, G. H., Huganir, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+AMPA+Receptor+Code+of+Synaptic+Plasticity.">The AMPA Receptor Code of Synaptic Plasticity.</a> Neuron. 100 (2), 314-329 (2018).</li><li>Lussier, M. P., Sanz-Clemente, A., Roche, K. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamic+Regulation+of+N-Methyl-d-aspartate+(NMDA)+and+alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic+Acid+(AMPA)+Receptors+by+Posttranslational+Modifications.">Dynamic Regulation of N-Methyl-d-aspartate (NMDA) and alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid (AMPA) Receptors by Posttranslational Modifications.</a> The Journal of Biological Chemistry. 290 (48), 28596-28603 (2015).</li><li>Traynelis, S. F., 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=Glutamate+receptor+ion+channels:+structure,+regulation,+and+function.">Glutamate receptor ion channels: structure, regulation, and function.</a> Pharmacological Reviews. 62 (3), 405-496 (2010).</li><li>Molnar, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-term+potentiation+in+cultured+hippocampal+neurons.">Long-term potentiation in cultured hippocampal neurons.</a> Seminars in Cell &amp; Developmental Biology. 22 (5), 506-513 (2011).</li><li>Seibenhener, M. L., Wooten, M. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+culture+of+hippocampal+neurons+from+prenatal+mice.">Isolation and culture of hippocampal neurons from prenatal mice.</a> Journal of Visualized Experiments. (65), (2012).</li><li>Nunez, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Primary+Culture+of+Hippocampal+Neurons+from+P0+Newborn+Rats.">Primary Culture of Hippocampal Neurons from P0 Newborn Rats.</a> Journal of Visualized Experiments. (19), (2008).</li><li>Lu, W., 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=Activation+of+synaptic+NMDA+receptors+induces+membrane+insertion+of+new+AMPA+receptors+and+LTP+in+cultured+hippocampal+neurons.">Activation of synaptic NMDA receptors induces membrane insertion of new AMPA receptors and LTP in cultured hippocampal neurons.</a> Neuron. 29 (1), 243-254 (2001).</li><li>Sanz-Clemente, A., Nicoll, R. A., Roche, K. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diversity+in+NMDA+Receptor+Composition:+Many+Regulators,+Many+Consequences.">Diversity in NMDA Receptor Composition: Many Regulators, Many Consequences.</a> The Neuroscientist: A Review Journal Bringing Neurobiology, Neurology and Psychiatry. 19 (1), 62-75 (2013).</li><li>Tham, D. K. L., Moukhles, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determining+Cell-surface+Expression+and+Endocytic+Rate+of+Proteins+in+Primary+Astrocyte+Cultures+Using+Biotinylation.">Determining Cell-surface Expression and Endocytic Rate of Proteins in Primary Astrocyte Cultures Using Biotinylation.</a> Journal of Visualized Experiments. (125), (2017).</li><li>Bermejo, M. K., Milenkovic, M., Salahpour, A., Ramsey, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+of+Synaptic+Plasma+Membrane+and+Postsynaptic+Density+Proteins+Using+a+Discontinuous+Sucrose+Gradient.">Preparation of Synaptic Plasma Membrane and Postsynaptic Density Proteins Using a Discontinuous Sucrose Gradient.</a> Journal of Visualized Experiments. (91), e51896 (2014).</li><li>Makino, H., Malinow, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=AMPA+receptor+incorporation+into+synapses+during+LTP:+the+role+of+lateral+movement+and+exocytosis.">AMPA receptor incorporation into synapses during LTP: the role of lateral movement and exocytosis.</a> Neuron. 64 (3), 381-390 (2009).</li><li>Bailey, D. M., Kovtun, O., Rosenthal, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antibody-Conjugated+Single+Quantum+Dot+Tracking+of+Membrane+Neurotransmitter+Transporters+in+Primary+Neuronal+Cultures.">Antibody-Conjugated Single Quantum Dot Tracking of Membrane Neurotransmitter Transporters in Primary Neuronal Cultures.</a> Methods in Molecular Biology. 1570, 165-177 (2017).</li><li>Trussell, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recording+and+analyzing+synaptic+currents+and+synaptic+potentials.">Recording and analyzing synaptic currents and synaptic potentials.</a> Current Protocols in Neuroscience. Chapter 6, Unit. , (2001).</li><li>Barreto-Chang, O. L., Dolmetsch, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Calcium+Imaging+of+Cortical+Neurons+using+Fura-2+AM.">Calcium Imaging of Cortical Neurons using Fura-2 AM.</a> Journal of Visualized Experiments. (23), e1067 (2009).</li></ol>

The interaction between a cell and its environment (e.g., communication with other cells, response to different stimuli, etc.), heavily relies on the correct expression of receptors at the cell surface. The rapid and fine-tuned regulation in surface-expressed receptor content enables proper cellular response to a constantly changing environment. In the particular case of neurons, alterations in the number, localization, and subunit composition of synaptically expressed receptors heavily influences synaptic communication,...

Cells utilize the active process of trafficking to mobilize proteins to specific subcellular localizations and exert strict spatiotemporal regulation over their function1. This process is especially important for transmembrane receptors, as cellular responses to different environmental stimuli rely on intracellular cascades triggered by receptor activation. Cells are able to modify these responses by altering the density, localization, and subunit composition of receptors expressed at the cell surface via receptor subcellular trafficking regulation2. Insertion of newly synthetized receptors into the plasma membrane, along with endocytosis and recycling of existing receptors are examples of trafficking processes that determine the net pool of surface-expressed receptors2. Many molecular mechanisms cooperate to regulate protein trafficking, including protein-protein interactions and posttranslational modifications such as phosphorylation, ubiquitination, or palmitoylation2.
Regulation of receptor trafficking is particularly required in strongly polarized cells with highly specialized structures. The paradigmatic example is the control of neuronal function by regulated trafficking of glutamate receptors (GluRs)3,4. Glutamate, the main excitatory neurotransmitter, binds and activates surface-expressed GluRs to control fundamental physiological neuronal functions such as synaptic neurotransmission and synaptic plasticity. The fact that altered GluR trafficking has been observed in a broad spectrum of neuropathies, ranging from neurodevelopmental disorders to neurodegenerative diseases, highlights the importance of this process5. Thus, understanding the molecular events that control GluR trafficking is of interest in many areas of research.
In this protocol, an antibody-feeding based method is used to quantify the level of surface-expressed GluRs in primary hippocampal neurons as well as evaluate how changes in internalization and recycling result in the observed net surface expression. The use of pharmacology and/or overexpression of exogenous receptors harboring specific mutations makes this protocol a particularly powerful approach for studying molecular mechanisms underlying neuronal adaptation to different environmental stimuli. A final example of the utility of this protocol is studying how multifactorial changes in the environment (such as in a disease models) affects GluR trafficking through the examination of surface expression in such models.
Using specific examples, it is initially demonstrated how a pharmacologic manipulation mimicking physiological synaptic stimulation [chemical LTP (cLTP)] increases the surface expression of the endogenous GluA1 subunit of the AMPA-type of GluRs (AMPARs)6. The trafficking of an overexpressed phospho-mimetic form of the GluN2B subunit of NMDA-type of GluRs (NMDARs) is also analyzed to exemplify how this protocol can be used to study the regulation of GluR trafficking by specific posttranslational modifications. Though these specific examples are used, this protocol can easily be applied to other GluRs and other receptors and proteins that possess antigenic extracellular domains. In the case that there are no antibodies available for extracellular domains, overexpression of extracellular epitope-tagged (e.g., Flag-, Myc-, GFP-tagged, etc.) proteins can assist in protein labeling.
The current protocol provides instructions for quantifying specific GluR subtype density and trafficking using specific antibodies. This protocol can be utilized to study 1) total GluR surface expression, 2) GluR internalization, and 3) GluR recycling. To study each process individually, it is advised to begin with sections 1 and 2 and continue with either section 3, 4, or 5. In all cases, finish with sections 6 and 8 (Figure 1).

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>18 mm dia. #1.5 thick coverglasses</td>
			<td>Neuvitro</td>
			<td>GG181.5</td>
			<td></td>
		</tr>
		<tr>
			<td>Alexa 555-conjugated goat anti-mouse secondary</td>
			<td>Life Technologies</td>
			<td>A21424</td>
			<td></td>
		</tr>
		<tr>
			<td>Alexa 555-conjugated goat anti-rabbit secondary</td>
			<td>Life Technologies</td>
			<td>A21429</td>
			<td></td>
		</tr>
		<tr>
			<td>Alexa 647-conjugated goat anti-mouse secondary</td>
			<td>Life Technologies</td>
			<td>A21236</td>
			<td></td>
		</tr>
		<tr>
			<td>Alexa 647-conjugated goat anti-rabbit secondary</td>
			<td>Life Technologies</td>
			<td>A21245</td>
			<td></td>
		</tr>
		<tr>
			<td>B27</td>
			<td>Gibco</td>
			<td>17504044</td>
			<td></td>
		</tr>
		<tr>
			<td>CaCl2</td>
			<td>Sigma</td>
			<td>C7902</td>
			<td></td>
		</tr>
		<tr>
			<td>Corning Costar Flat Bottom Cell Culture Plates</td>
			<td>Corning</td>
			<td>3513</td>
			<td></td>
		</tr>
		<tr>
			<td>Dynasore</td>
			<td>Tocris</td>
			<td>2897</td>
			<td></td>
		</tr>
		<tr>
			<td>Glucose</td>
			<td>Sigma</td>
			<td>G8270</td>
			<td></td>
		</tr>
		<tr>
			<td>Glycine</td>
			<td>Tocris</td>
			<td>0219</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat anti-rabbit Fab fragments</td>
			<td>Sigma</td>
			<td>SAB3700970</td>
			<td></td>
		</tr>
		<tr>
			<td>HEPES</td>
			<td>Sigma</td>
			<td>H7006</td>
			<td></td>
		</tr>
		<tr>
			<td>KCl</td>
			<td>Sigma</td>
			<td>P9541</td>
			<td></td>
		</tr>
		<tr>
			<td>L-Glutamine</td>
			<td>Sigma</td>
			<td>G7513</td>
			<td></td>
		</tr>
		<tr>
			<td>Lipofectamine 2000</td>
			<td>Invitrogen</td>
			<td>11668019</td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse anti-GluA1 antibody</td>
			<td>Millipore</td>
			<td>MAB2263</td>
			<td></td>
		</tr>
		<tr>
			<td>NaCl</td>
			<td>Sigma</td>
			<td>S6546</td>
			<td></td>
		</tr>
		<tr>
			<td>Neurobasal Media</td>
			<td>Gibco</td>
			<td>21103049</td>
			<td></td>
		</tr>
		<tr>
			<td>NGS</td>
			<td>Abcam</td>
			<td>Ab7481</td>
			<td></td>
		</tr>
		<tr>
			<td>Parafilm</td>
			<td>Bemis</td>
			<td>PM999</td>
			<td></td>
		</tr>
		<tr>
			<td>PBS</td>
			<td>Gibco</td>
			<td>10010023</td>
			<td></td>
		</tr>
		<tr>
			<td>Pelco BioWave</td>
			<td>Ted Pella</td>
			<td>36500</td>
			<td></td>
		</tr>
		<tr>
			<td>PFA</td>
			<td>Alfa Aesar</td>
			<td>43368</td>
			<td></td>
		</tr>
		<tr>
			<td>Picrotoxin</td>
			<td>Tocris</td>
			<td>1128</td>
			<td></td>
		</tr>
		<tr>
			<td>Poly-D-lysine hydrobromide</td>
			<td>Sigma</td>
			<td>P7280</td>
			<td></td>
		</tr>
		<tr>
			<td>ProLong Gold Antifade Mountant</td>
			<td>Life Technologies</td>
			<td>P36934</td>
			<td></td>
		</tr>
		<tr>
			<td>Rabbit anti-GFP antibody</td>
			<td>Invitrogen</td>
			<td>A11122</td>
			<td></td>
		</tr>
		<tr>
			<td>Rabbit anti-PSD-95 antibody</td>
			<td>Cell Signaling</td>
			<td>2507</td>
			<td></td>
		</tr>
		<tr>
			<td>Strychnine</td>
			<td>Tocris</td>
			<td>2785</td>
			<td></td>
		</tr>
		<tr>
			<td>Sucrose</td>
			<td>Sigma</td>
			<td>S0389</td>
			<td></td>
		</tr>
		<tr>
			<td>Superfrost plus microscope slides</td>
			<td>Fisher</td>
			<td>12-550-15</td>
			<td></td>
		</tr>
		<tr>
			<td>Triton X-100</td>
			<td>Sigma</td>
			<td>X100</td>
			<td></td>
		</tr>
		<tr>
			<td>TTX</td>
			<td>Tocris</td>
			<td>1078</td>
			<td></td>
		</tr>
	</tbody>
</table>

an antibody feeding approach to study glutamate receptor trafficking in dissociated primary hippocampal cultures

Cellular responses to external stimuli heavily rely on the set of receptors expressed at the cell surface at a given moment. Accordingly, the population of surface-expressed receptors is constantly adapting and subject to strict mechanisms of regulation. The paradigmatic example and one of the most studied trafficking events in biology is the regulated control of the synaptic expression of glutamate receptors (GluRs). GluRs mediate the vast majority of excitatory neurotransmission in the central nervous system and control physiological activity-dependent functional and structural changes at the synaptic and neuronal levels (e.g., synaptic plasticity). Modifications in the number, location, and subunit composition of surface expressed GluRs deeply affect neuronal function and, in fact, alterations in these factors are associated with different neuropathies. Presented here is a method to study GluR trafficking in dissociated hippocampal primary neurons. An &#34;antibody-feeding&#34; approach is used to differentially visualize GluR populations expressed at the surface and internal membranes. By labeling surface receptors on live cells and fixing them at different times to allow for receptors endocytosis and/or recycling, these trafficking processes can be evaluated and selectively studied. This is a versatile protocol that can be used in combination with pharmacological approaches or overexpression of altered receptors to gain valuable information about stimuli and molecular mechanisms affecting GluR trafficking. Similarly, it can be easily adapted to study other receptors or surface expressed proteins.

This protocol to study glutamate receptor trafficking is based on differential labeling of receptors expressed at the cell surface and those expressed in internal membranes. Segregation is achieved by the labeling the receptors before and after membrane permeabilization, using the same primary antibody but a secondary antibody conjugated to a different fluorophore. As outlined by the optional steps included the protocol, this is a very versatile method for interrogating different receptor...

Watch this Scientific Journal Video about An Antibody Feeding Approach to Study Glutamate Receptor Trafficking in Dissociated Primary Hippocampal Cultures at JoVE.com

An Antibody Feeding Approach to Study Glutamate Receptor Trafficking in Dissociated Primary Hippocampal Cultures

This article presents a method to study glutamate receptor (GluR) trafficking in dissociated primary hippocampal cultures. Using an antibody-feeding approach to label endogenous or overexpressed receptors in combination with pharmacological approaches, this method allows for the identification of molecular mechanisms regulating GluR surface expression by modulating internalization or recycling processes.

Cellular responses to external stimuli heavily rely on the set of receptors expressed at the cell surface at a given moment. Accordingly, the population ...

Research

JoVE Journal

Neuroscience

Organotypic Hippocampal Slice Cultures

The hippocampus, a component of the limbic system, plays important roles in long-term memory and spatial navigation 1. Hippocampal neurons can modify the ...

Fast Micro-iontophoresis of Glutamate and GABA: A Useful Tool to Investigate Synaptic Integration

One of the fundamental interests in neuroscience is to understand the integration of excitatory and inhibitory inputs along the very complex structure of ...

Calcium Phosphate Transfection of Primary Hippocampal Neurons

Calcium phosphate precipitation is a convenient and economical method for transfection of cultured cells. With optimization, it is possible to use this ...

Membrane Potential Dye Imaging of Ventromedial Hypothalamus Neurons From Adult Mice to Study Glucose Sensing

Studies of neuronal activity are often performed using neurons from rodents less than 2 months of age due to the technical difficulties associated with ...

Brain Slice Biotinylation: An Ex Vivo Approach to Measure Region-specific Plasma Membrane Protein Trafficking in Adult Neurons

Brain Slice Biotinylation: An Ex Vivo Approach to Measure Region-specific Plasma Membrane Protein Trafficking in Adult Neurons

Regulated endocytic trafficking is the central mechanism facilitating a variety of neuromodulatory events, by dynamically controlling receptor, ion ...

Using an &#945;-Bungarotoxin Binding Site Tag to Study GABA A Receptor Membrane Localization and Trafficking

Using an ÃƒÅ½Ã‚Â±-Bungarotoxin Binding Site Tag to Study GABA A Receptor Membrane Localization and Trafficking

It is increasingly evident that neurotransmitter receptors, including ionotropic GABA A receptors (GABAAR), exhibit highly dynamic trafficking and cell ...

The Analysis of Neurovascular Remodeling in Entorhino-hippocampal Organotypic Slice Cultures

Ischemic brain injury is among the most common and devastating conditions compromising proper brain function and often leads to persisting functional ...

Stripe Assay to Study the Attractive or Repulsive Activity of a Protein Substrate Using Dissociated Hippocampal Neurons

Growing axons develop a highly motile structure at their tip, termed the growth cone. The growth cone contacts extracellular environmental cues to ...

Low-Density Primary Hippocampal Neuron Culture

The ability to probe the structure and physiology of individual nerve cells in culture is crucial to the study of neurobiology, and allows for flexibility ...

Organotypic Hippocampal Slice Cultures As a Model to Study Neuroprotection and Invasiveness of Tumor Cells

In organotypic hippocampal slice cultures (OHSC), the morphological and functional characteristics of both neurons and glial cells are well preserved. ...