Wir möchten Jennifer Bair und Einat Snir sowie das Institut für Humangenetik der Universität Iowa für ihre Unterstützung bei der Vorbereitung und Bearbeitung von Proben anerkennen.

<ol>
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H., Dacey, D., Lucas, R., Hattar, S., Matynia, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Melanopsin-Positive+Intrinsically+Photosensitive+Retinal+Ganglion+Cells:+From+Form+to+Function.">Melanopsin-Positive Intrinsically Photosensitive Retinal Ganglion Cells: From Form to Function.</a> J. Neurosci. 31 (45), 16094-16101 (2011).</li><li>Eberwine, J., Miyashiro, K., Kacharmina, J. E., Job, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Local+translation+of+classes+of+mRNAs+that+are+targeted+to+neuronal+dendrites.">Local translation of classes of mRNAs that are targeted to neuronal dendrites.</a> Proc. Natl. Acad. 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Z., 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=Highly+Parallel+Genome-wide+Expression+Profiling+of+Individual+Cells+Using+Nanoliter+Droplets.">Highly Parallel Genome-wide Expression Profiling of Individual Cells Using Nanoliter Droplets.</a> Cell. 161 (5), 1202-1214 (2015).</li><li>Usoskin, 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=Unbiased+classification+of+sensory+neuron+types+by+large-scale+single-cell+RNA+sequencing.">Unbiased classification of sensory neuron types by large-scale single-cell RNA sequencing.</a> Nat. Neurosci. 18 (1), 145-153 (2015).</li><li>Poulin, J. F., Zou, J., Drouin-Ouellet, J., Kim, K. Y. A., Cicchetti, F., Awatramani, R. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Defining+midbrain+dopaminergic+neuron+diversity+by+single-cell+gene+expression+profiling.">Defining midbrain dopaminergic neuron diversity by single-cell gene expression profiling.</a> Cell. Rep. 9 (3), 930-943 (2014).</li><li>Gross, A., Schoendube, J., Zimmermann, S., Steeb, M., Zengerle, R., Koltay, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Technologies+for+Single-Cell+Isolation.">Technologies for Single-Cell Isolation.</a> Int. J. Mol. 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J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Grouping+and+classifying+electrophysiologically-defined+classes+of+neocortical+neurons+by+single+cell,+whole-genome+expression+profiling.">Grouping and classifying electrophysiologically-defined classes of neocortical neurons by single cell, whole-genome expression profiling.</a> Front. Mol. Neurosci. 3 (10), 1-11 (2010).</li><li>Fuzik, J., 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=Integration+of+electrophysiological+recordings+with+single-cell+RNA-seq+data+identifies+neuronal+subtypes.">Integration of electrophysiological recordings with single-cell RNA-seq data identifies neuronal subtypes.</a> Nat. Biotechnol. 34 (2), 175-183 (2016).</li><li>Schmidt, T. M., Kofuji, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+isolated+retinal+preparation+to+record+light+response+from+genetically+labeled+retinal+ganglion+cells.">An isolated retinal preparation to record light response from genetically labeled retinal ganglion cells.</a> J. Vis. Exp. (47), e2367 (2011).</li><li>Schmidt, T. M., Kofuji, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+and+morphological+differences+among+intrinsically+photosensitive+retinal+ganglion+cells.">Functional and morphological differences among intrinsically photosensitive retinal ganglion cells.</a> J Neurosci. 29 (2), 476-482 (2009).</li><li>Schmidt, T. M., Kofuji, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structure+and+Function+of+Bistratified+Intrinsically+Photosensitive+Retinal+Ganglion+Cells+in+the+Mouse.">Structure and Function of Bistratified Intrinsically Photosensitive Retinal Ganglion Cells in the Mouse.</a> J Comp Neurol. 519 (8), 1492-1504 (2011).</li><li>Schmidt, T. M., Kofuji, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+cone+pathway+influence+on+intrinsically+photosensitive+retinal+ganglion+cell+subtypes.">Differential cone pathway influence on intrinsically photosensitive retinal ganglion cell subtypes.</a> J Neurosci. 30 (48), 16262-16271 (2010).</li><li>Clontech Laboratories I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> SMARTerTM Ultra Low RNA Kit for Illumina&#174; Sequencing. , (2013).</li><li>Trombetta, J. J., Gennert, D., Lu, D., Satija, R., Shalek, A. 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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=A+Role+for+Melanopsin+in+Alpha+Retinal+Ganglion+Cells+and+Contrast+Detection.">A Role for Melanopsin in Alpha Retinal Ganglion Cells and Contrast Detection.</a> Neuron. 82 (4), 781-788 (2014).</li><li>Sanes, J. R., Masland, R. 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+Types+of+Retinal+Ganglion+Cells:+Current+Status+and+Implications+for+Neuronal+Classification.">The Types of Retinal Ganglion Cells: Current Status and Implications for Neuronal Classification.</a> Annu. Rev. Neurosci. 38, 221-246 (2014).</li><li>Goetz, J. J., Trimarchi, J. 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Die Autoren haben nichts zu offenbaren.

Unser Protokoll demonstriert durch eine schnelle und einfach zu bedienende Anleitung eine Methode zur Vorbereitung einzelner Zellen identifizierter morphologischer Klassen für qualitativ hochwertige Sequenzierung mit wenig Verletzung der Probe. In dem vorliegenden Manuskript werden intrinsisch lichtempfindliche retinale Ganglienzellen morphologisch charakterisiert, isoliert und für RNA-Seq vorbereitet. Während der Netzhauthandhabung können zelluläre Spannungen auftreten Aus diesem Grund ersetzen wir jedes Stück Ge...

Die neuronale Diversität wird im gesamten Zentralnervensystem beobachtet, insbesondere in der Wirbeltierhaut, ein hochspezialisiertes Gewebe, bestehend aus 1 glialen und 6 neuronalen Zelltypen, die aus einer Population der Netzhautvorläuferzellen 1 , 2 , 3 entstehen. Viele Subtypen von Zellen können funktionell, morphologisch und genetisch klassifiziert werden. Ziel dieses Protokolls ist es, die genetische Variabilität von Zelltypen an ihre identifizierbaren funktionellen und / oder morphologischen Eigenschaften zu binden. Eine Reihe von Genen wurden für die Klassifizierung von Zellen identifiziert, aber viele Subtypen gehen weiterhin uncharakterisiert, da sie einen kleinen Bruchteil der Gesamtbevölkerung darstellen. Die Identifizierung von Genen innerhalb dieser spezifischen Subtypen wird ein besseres Verständnis der neuronalen Vielfalt innerhalb der Netzhaut ermöglichen und kann auch die Diversifizierung der neuralen Zellen anderswo beleuchten. FuDarüber hinaus erlauben Single-Cell-Studien die Aufdeckung neuer Zelltypen, die aufgrund ihrer geringen Repräsentation unter der Gesamtbevölkerung 4 , 5 , 6 , 7 übersehen werden können . Einer der Vorteile der Single-Cell-Transkriptomik ist, dass einzigartige Marker oder Kombinationen von Markern, die einen bestimmten zellulären Subtyp definieren, entdeckt werden können. Diese können dann verwendet werden, um genetischen Zugang zu diesem Zelltyp für verschiedene Manipulationen zu gewinnen. Zum Beispiel verwenden wir dieses Protokoll zur Charakterisierung der zelltypspezifischen Gene einer Untergruppe von retinalen Ganglienzellen, die das Photopigment Melanopsin exprimieren. Die Verwendung eines fluoreszierenden Markers in Melanopsin-exprimierenden retinalen Ganglienzellen ermöglicht die Untersuchung dieser Zellen, da sie aufgrund ihrer Expression eines bekannten Gens zusammengehäuft sind. Interessanterweise gibt es fünf bekannte Subtypen dieser Zelle PopuLation in der Maus Retina 8 . Um also RNA aus Zellen jedes Typs zu isolieren, haben wir im Rahmen des transgenen Modells etablierte morphologische Klassifikationen verwendet, um jeden Subtyp vor der Zellisolation zu identifizieren. Diese Technik ermöglicht sowohl die Charakterisierung von Zellen als auch für ihre Isolierung direkt aus der Netzhaut, ohne die Notwendigkeit einer Gewebedissoziation, die eine Stressreaktion innerhalb von Zellen und eine Kontamination aufgrund von abgetrennten Dendriten verursachen kann 9 . In den vergangenen Jahren ist eine Vielzahl neuer Techniken aufgetaucht, da sich die RNA-Seq-Methode weiterentwickelt. Diese Werkzeuge ermöglichen eine maximierte Zellaufnahme und eine höhere Kosteneffizienz bei Annäherung an die Frage 4 , 7 , 10 , 11 , 12 , 13 . Doch währendDiese Techniken waren hervorragende Stepping-Steine, gibt es eine Reihe von Hürden noch begegnet, dass dieses Protokoll in der Lage ist, Adresse. Zuerst isolieren viele der gegenwärtigen Verfahren Zellen aus dissoziiertem Gewebe und versuchen, entweder Hauptkomponentenanalyse oder hierarchische Clustering Post-hoc zu verwenden, um die Zellklassifizierung zu bestimmen. Das Verlassen auf diese Werkzeuge, um Subtypen zu klassifizieren, kann keine zuverlässigen Ergebnisse liefern und kann dazu führen, dass man neue Wege findet, um diese Daten für die Korrelation eines genetischen Markers zu einem funktionellen Zelltyp zu validieren. Das Erfordernis der Dissoziation in anderen Protokollen kann manchmal zu Gewebeschäden führen und kann dazu führen, dass neuronale Prozesse abgetrennt werden, was zu einem möglichen Verlust an mRNA führt. Weiterhin können in den dissoziierten Zellpräparaten die Stressreaktionen beginnen, die Transkriptome dieser Zellen zu beeinflussen 14 . Dieses Protokoll überwindet diese Herausforderungen durch die Bestimmung der funktionellen Zelltyp vor der Isolierung, und es hält besser die hDie Fähigkeit, das Netzhautgewebe intakt zu halten. Eine Technik wurde im Jahr 2014 eingeführt und bestand aus der in vivo Analyse des Transkriptoms der lebenden Zellen 15 . Während diese Technik die Untersuchung des Transkriptoms mit minimaler mechanischer Störung des Gewebes ermöglicht, fehlt es an der Fähigkeit, spezifische Zelltypen innerhalb des Gewebes zu klassifizieren, bevor sie ihre Transkriptome untersuchen, ohne eine sehr spezifische Reportermaus zu verwenden. Unser Protokoll erfordert keinen spezifischen Reporter, da wir die Zellfüllung und die Elektrophysiologie nutzen, um Zellen vor ihrer Isolation zu charakterisieren. Eine weitere Einschränkung dieses früheren Protokolls besteht darin, dass es eine spezifische Wellenlänge benötigt, um das photoaktivierbare Element anzuregen, während unser Protokoll die Verwendung eines fluoreszierenden Reporters und eines fluoreszierenden Farbstoffs ermöglicht, die leicht verfügbar sind oder von jedem Labor einzeln ausgewählt werden können. Dennoch haben andere Laboratorien die beiden Methoden der Elektrizität geheiratetOphysiologie und Transkriptomik für das Studium der Zellvielfalt. Die Verwendung von Patch-Clamp-Aufnahmen zur Charakterisierung der Funktion einer Zelle vor ihrer Isolation wurde auf dissoziierten Neuronen durchgeführt 16 und in einigen Fällen ist sie der Verwendung der Mikroarray-Analyse 17 für diese Studien vorausgegangen. Die gleichen Komplikationen treten bei jenen Ansätzen auf, da sie eine Gewebedissoziation oder die Verwendung von Mikroarray-Technologie erfordern, die auf der Hybridisierung von Proben auf verfügbare Sonden beruht. Einer der jüngsten Fortschritte war die Entwicklung von Patch-Seq, einer Technik, die den Einsatz von Patch-Clamp-Aufnahmen und RNA-Seq-Technologie kombiniert, um Zellen aus Ganzhirn-Scheiben zu verstehen. Während diese Technik ihre Ähnlichkeiten mit dem hier vorgestellten Protokoll hat, ist es wieder wichtig zu beachten, dass unser Ansatz es dem Gewebe ermöglicht, für die Gesundheit der Zellen intakt zu bleiben. Hier stellen wir ein Protokoll für die optimizat vorIon dieser Allianz, die qualitativ hochwertige Single-Cell-Bibliotheken für den Einsatz von RNA-Seq generiert, um eine hohe Lesetiefe und Mapping-Abdeckung zu erhalten.

<table border="0" cellpadding="0" cellspacing="0" width="907">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:257px;">Ames&#39; Medium</td>
			<td style="width:171px;">Sigma Aldrich</td>
			<td style="width:108px;">A1420-10X1L</td>
			<td style="width:372px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Sodium Bicarbonate</td>
			<td>Sigma Aldrich</td>
			<td>S8875</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">K-gluconate</td>
			<td>Spectrum Chemical</td>
			<td>PO178</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">EGTA</td>
			<td>Sigma Aldrich</td>
			<td>E4378</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">HEPES</td>
			<td>Sigma Aldrich</td>
			<td>H3375</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Diethyl pyrocarbonate (DEPC)</td>
			<td>Sigma Aldrich</td>
			<td>D5758</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Alexa Fluor 594 Hydrazide</td>
			<td>Invitrogen</td>
			<td>A10442</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Collagenase</td>
			<td>Worthington Biochemical&#160;</td>
			<td>LS005273</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hyaluronidase</td>
			<td>Worthington Biochemical&#160;</td>
			<td>LS002592</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Petri dish (35mm diameter)</td>
			<td>Thermo Fisher Scientific</td>
			<td>153066</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Ophthalmologic scissors</td>
			<td>Fine Science Tools</td>
			<td>15000-00</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">#5 Forceps</td>
			<td>Fine Science Tools</td>
			<td>11252-30</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Microplate Shaker</td>
			<td>Fisher Scientific</td>
			<td>13-687-708</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Glass Micropipette</td>
			<td>Sutter</td>
			<td>BF120-69-10</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Micropipette Puller</td>
			<td>Sutter</td>
			<td></td>
			<td>P-1000 horizontal pipette puller</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1mL syringe</td>
			<td>Fisher Scientific</td>
			<td>14-823-2F</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Flexible tubing</td>
			<td>Fisher Scientific</td>
			<td>14-171</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">TCL lysis buffer</td>
			<td>Qiagen</td>
			<td>1031576</td>
			<td>Lysis Buffer 1</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">&#946;-mercaptoethanol</td>
			<td>Sigma Aldrich</td>
			<td>M3148</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">RNase-Free Water</td>
			<td>Qiagen</td>
			<td>129112</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">0.2 ml PCR tubes</td>
			<td>Eppendorf</td>
			<td>30124359</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Ethyl Alcohol, Pure</td>
			<td>Sigma Aldrich</td>
			<td>E7023</td>
			<td>Ethanol</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Analog Vortex Mixer</td>
			<td>Thermo Fisher Scientific</td>
			<td>02215365</td>
			<td>Vortex</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Mini Centrifuge</td>
			<td>Thermo Fisher Scientific</td>
			<td>05-090-100</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Agencourt RNAClean XP Beads</td>
			<td>Beckman Coulter</td>
			<td>A63987</td>
			<td>RNA magnetic beads</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">MagnaBlot II Magnetic Separator</td>
			<td>Promega</td>
			<td>V8351</td>
			<td>Magnetic stand</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1.5 ml MCT Graduated Tubes</td>
			<td>Thermo Fisher Scientific</td>
			<td>05-408-129</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Smart-Seq v4 Ultra Low Input RNA Kit</td>
			<td>Clontech</td>
			<td>634888</td>
			<td>Reagents for Reverse Transcription and PCR Amplification</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">10X Lysis Buffer</td>
			<td></td>
			<td></td>
			<td>Lysis Buffer 2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">5X Ultra Low First-Strand Buffer</td>
			<td></td>
			<td></td>
			<td>Buffer 1</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">3&#39; SMART-Seq CDS Primer II A</td>
			<td></td>
			<td></td>
			<td>Primer II</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">SMART-Seq v4 Oligonucleotide</td>
			<td></td>
			<td></td>
			<td>Oligonucleotide</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">SMARTScribe Rverse Transcriptase</td>
			<td></td>
			<td></td>
			<td>Reverse Transcriptase</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">2X SeqAmp PCR Buffer</td>
			<td></td>
			<td></td>
			<td>PCR Buffer</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">PCR Primer II A</td>
			<td></td>
			<td></td>
			<td>PCR Primer</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">SeqAmp DNA Polymerase</td>
			<td></td>
			<td></td>
			<td>DNA Polymerase</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Mastercycler pro S</td>
			<td>Eppendorf</td>
			<td>950030020</td>
			<td>Thermocycler</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Agencourt AMPure XP Beads</td>
			<td>Beckman Coulter</td>
			<td>A63881</td>
			<td>DNA magnetic beads</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">2100 Bioanalyzer</td>
			<td>Agilent Technologies</td>
			<td>G2939AA</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">HS Bioanalyzer Chips &#38; Reagents</td>
			<td>Agilent Technologies</td>
			<td>5067-4626</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Qubit HS Assay Kit</td>
			<td>Thermo Fisher Scientific</td>
			<td>Q32851</td>
			<td>For the calculation of sample concentrations</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Qubit Assay Tubes</td>
			<td>Thermo Fisher Scientific</td>
			<td>Q32856</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Qubit 2.0 Fluorometer</td>
			<td>Thermo Fisher Scientific</td>
			<td>Q32866</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Nextera XT DNA Sample Preparation Kit</td>
			<td>Illumina</td>
			<td>FC-131-1024</td>
			<td>Reagents for Tagmentation and Index Coupling</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">TD Buffer</td>
			<td></td>
			<td></td>
			<td>Buffer 2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">ATM</td>
			<td></td>
			<td></td>
			<td>Tagmentation Mix</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">NT Buffer</td>
			<td></td>
			<td></td>
			<td>Tagmentation Neutralizing Buffer</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">NPM</td>
			<td></td>
			<td></td>
			<td>PCR Master Mix</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Nextera XT Index Kit</td>
			<td>Illumina</td>
			<td>FC-131-1001</td>
			<td>Indices for Tagmentation</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">N501</td>
			<td></td>
			<td></td>
			<td>White 1</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">N502</td>
			<td></td>
			<td></td>
			<td>White 2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">N701</td>
			<td></td>
			<td></td>
			<td>Orange 1</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">N702</td>
			<td></td>
			<td></td>
			<td>Orange 2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">HiSeq 2500</td>
			<td>Illumina</td>
			<td>SY-401-2501</td>
			<td>For completing sequencing of samples</td>
		</tr>
	</tbody>
</table>

single-cell rna-seq of defined subsets of retinal ganglion cells

Die Entdeckung von zelltypspezifischen Markern kann Einblicke in die zelluläre Funktion und die Ursprünge der zellulären Heterogenität geben. Mit einem jüngsten Push für das verbesserte Verständnis der neuronalen Vielfalt ist es wichtig, Gene zu identifizieren, deren Ausdruck verschiedene Subpopulationen von Zellen definiert. Die Netzhaut dient als hervorragendes Modell für die Untersuchung der zentralen Nervensystem-Vielfalt, da sie aus mehreren Hauptzelltypen besteht. Die Untersuchung jeder Hauptklasse von Zellen hat genetische Marker ergeben, die die Identifizierung dieser Populationen erleichtern. Allerdings gibt es mehrere Subtypen von Zellen innerhalb jeder dieser großen retinalen Zellklassen, und wenige dieser Subtypen haben genetische Marker bekannt, obwohl viele durch Morphologie oder Funktion charakterisiert wurden. Eine Kenntnis von genetischen Markern für einzelne retinale Subtypen würde die Untersuchung und Kartierung von Hirnzielen ermöglichen, die sich auf spezifische visuelle Funktionen beziehen und auch einen Einblick in die Gennetze vermitteln könnenPflegen zelluläre Vielfalt. Die gegenwärtigen Wege, die verwendet wurden, um die genetischen Marker von Subtypen zu identifizieren, besitzen Nachteile, wie die Klassifizierung von Zelltypen nach der Sequenzierung. Dies stellt eine Herausforderung für die Datenanalyse dar und erfordert rigorose Validierungsmethoden, um sicherzustellen, dass Cluster Zellen der gleichen Funktion enthalten. Wir schlagen eine Technik zur Identifizierung der Morphologie und Funktionalität einer Zelle vor der Isolierung und Sequenzierung vor, die eine leichtere Identifizierung von subtypspezifischen Markern ermöglicht. Diese Technik kann auf nicht-neuronale Zelltypen sowie auf seltene Populationen von Zellen mit geringfügigen Variationen erweitert werden. Dieses Protokoll liefert hervorragende Daten, da viele Bibliotheken Lese-Tiefen von mehr als 20 Millionen Lesungen für einzelne Zellen zur Verfügung gestellt haben. Diese Methodik überwindet viele der Hürden, die von Single-Cell RNA-Seq präsentiert werden, und kann für Forscher geeignet sein, die darauf abzielen, Zelltypen auf einfache und hocheffiziente Weise zu profilieren.

Zelltypen werden nach der Farbstoffinjektion leicht klassifiziert Abbildung 1 zeigt ein Beispiel eines GFP + RGC vor und nach der Fluoreszenz-Tracer-Füllung. Diese Zelle wurde anhand ihrer Expression von GFP in der transgenen Linie identifiziert (Abbildung 1A ). Eine dichte Abdichtung wurde mit einer feinen Spitze, gezogenen Glaselektrode auf dem Soma dieser Zelle gebildet. Um den Subtyp zu char...

Watch this Scientific Journal Video about Single-cell RNA-Seq of Defined Subsets of Retinal Ganglion Cells at JoVE.com

Single-cell RNA-Seq of Defined Subsets of Retinal Ganglion Cells

Hier präsentieren wir einen kombinatorischen Ansatz zur Klassifizierung von neuronalen Zelltypen vor der Isolierung und für die anschließende Charakterisierung von einzelligen Transkriptomen. Dieses Protokoll optimiert die Probenvorbereitung für eine erfolgreiche RNA-Sequenzierung (RNA-Seq) und beschreibt eine Methodik, die speziell für das verbesserte Verständnis der zellulären Vielfalt entwickelt wurde.

Einzelzell-RNA-Seq von definierten Subsets von Retinal-Ganglion-Zellen

The discovery of cell type-specific markers can provide insight into cellular function and the origins of cellular heterogeneity. With a recent push for ...

single-cell-rna-seq-of-defined-subsets-of-retinal-ganglion-cells

Universidad de Cartagena UDEC

Research

JoVE Journal

Neuroscience

13.7K Aufrufe.  Iowa State University.  Hier präsentieren wir einen kombinatorischen Ansatz zur Klassifizierung von neuronalen Zelltypen vor der Isolierung und für die anschließende Charakterisierung von einzelligen Transkriptomen. Dieses Protokoll optimiert die Probenvorbereitung für eine erfolgreiche RNA-Sequenzierung (RNA-Seq) und beschreibt eine Methodik, die speziell für das verbesserte Verständnis der zellulären Vielfalt entwickelt wurde. 

Serie: Single-cell RNA-Seq of Defined Subsets of Retinal Ganglion Cells

An Isolated Retinal Preparation to Record Light Response from Genetically Labeled Retinal Ganglion Cells

The first steps in vertebrate vision take place when light stimulates the rod and cone photoreceptors of the retina 1. This information is then segregated into what are known as the ON and OFF pathways. The photoreceptors signal light information to the bipolar cells (BCs), which depolarize in response to increases (On BCs) or decreases (Off BCs) in light intensity. This segregation of light information is maintained at the level of the retinal ganglion cells (RGCs), which have dendrites stratifying in either the Off sublamina of the inner plexiform layer (IPL), where they receive direct excitatory input from Off BCs, or stratifying in the On sublamina of the IPL, where they receive direct excitatory input from On BCs. This segregation of information regarding increases or decreases in illumination (the On and Off pathways) is conserved and signaled to the brain in parallel.
The RGCs are the output cells of the retina, and are thus an important cell to study in order to understand how light information is signaled to visual nuclei in the brain. Advances in mouse genetics over recent decades have resulted in a variety of fluorescent reporter mouse lines where specific RGC populations are labeled with a fluorescent protein to allow for identification of RGC subtypes 2 3 4 and specific targeting for electrophysiological recording. Here, we present a method for recording light responses from fluorescently labeled ganglion cells in an intact, isolated retinal preparation. This isolated retinal preparation allows for recordings from RGCs where the dendritic arbor is intact and the inputs across the entire RGC dendritic arbor are preserved. This method is applicable across a variety of ganglion cell subtypes and is amenable to a wide variety of single-cell physiological techniques.

This article provides a description of how to dissect and record from the isolated retinal preparation in mouse. In particular, we describe how to record light responses from a fluorescently labeled ganglion cell population and subsequently identify and analyze its morphology.

Eine isolierte Retinal Vorbereitung auf leichte Ansprache aus genetisch markierten retinalen Ganglienzellen Rekord

The first steps in vertebrate vision take place when light stimulates the rod and cone photoreceptors of the retina 1.  This information is then ...

Forschung

Neurowissenschaften

Transfection of Mouse Retinal Ganglion Cells by in vivo Electroporation

The targeting and refinement of RGC projections to the midbrain is a popular and powerful model system for studying how precise patterns of neural connectivity form during development. In mice, retinofugal projections are arranged in a topographic manner and form eye-specific layers in the Lateral Geniculate Nucleus (dLGN) of the thalamus and the Superior Colliculus (SC). The development of these precise patterns of retinofugal projections has typically been studied by labeling populations of RGCs with fluorescent dyes and tracers, such as horseradish peroxidase1-4. However, these methods are too coarse to provide insight into developmental changes in individual RGC axonal arbor morphology that are the basis of retinotopic map formation. They also do not allow for the genetic manipulation of RGCs.
Recently, electroporation has become an effective method for providing precise spatial and temporal control for delivery of charged molecules into the retina5-11. Current retinal electroporation protocols do not allow for genetic manipulation and tracing of retinofugal projections of a single or small cluster of RGCs in postnatal mice. It has been argued that postnatal in vivo electroporation is not a viable method for transfecting RGCs since the labeling efficiency is extremely low and hence requires targeting at embryonic ages when RGC progenitors are undergoing differentiation and proliferation6. 
In this video we describe an in vivo electroporation protocol for targeted delivery of genes, shRNA, and fluorescent dextrans to murine RGCs postnatally. This technique provides a cost effective, fast and relatively easy platform for efficient screening of candidate genes involved in several aspects of neural development including axon retraction, branching, lamination, regeneration and synapse formation at various stages of circuit development. In summary we describe here a valuable tool which will provide further insights into the molecular mechanisms underlying sensory map development.

Transfection of Mouse Retinal Ganglion Cells by in vivo Electroporation

We demonstrate an in vivo electroporation protocol for transfecting single or small clusters of retinal ganglion cells (RGCs) and other retinal cell types in postnatal mice over a wide range of ages. The ability to label and genetically manipulate postnatal RGCs in vivo is a powerful tool for developmental studies.

Die Transfektion von Maus retinalen Ganglienzellen durch In vivo Elektroporation

The targeting and refinement of RGC projections to the midbrain is a popular and powerful model system for studying how precise patterns of neural ...

An Optic Nerve Crush Injury Murine Model to Study Retinal Ganglion Cell Survival

Injury to the optic nerve can lead to axonal degeneration, followed by a gradual death of retinal ganglion cells (RGCs), which results in irreversible vision loss. Examples of such diseases in human include traumatic optic neuropathy and optic nerve degeneration in glaucoma. It is characterized by typical changes in the optic nerve head, progressive optic nerve degeneration, and loss of retinal ganglion cells, if uncontrolled, leading to vision loss and blindness.
The optic nerve crush (ONC) injury mouse model is an important experimental disease model for traumatic optic neuropathy, glaucoma, etc. In this model, the crush injury to the optic nerve leads to gradual retinal ganglion cells apoptosis. This disease model can be used to study the general processes and mechanisms of neuronal death and survival, which is essential for the development of therapeutic measures. In addition, pharmacological and molecular approaches can be used in this model to identify and test potential therapeutic reagents to treat different types of optic neuropathy.
Here, we provide a step by step demonstration of (I) Baseline retrograde labeling of retinal ganglion cells (RGCs) at day 1, (II) Optic nerve crush injury at day 4, (III) Harvest the retinae and analyze RGC survival at day 11, and (IV) Representative result.

This protocol shows how to retrogradely label retinal ganglion cells, and how to subsequently make an optic nerve crush injury in order to analyze retinal ganglion cell survival and apoptosis. It is an experimental disease model for different types of optic neuropathy, including glaucoma.

Ein Optic Nerve Crush Injury Mausmodell zur retinalen Ganglienzellen Survival Study

Injury to the optic nerve can lead to axonal degeneration, followed by a gradual death of retinal ganglion cells (RGCs), which results in irreversible ...

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 fundamental biological mechanisms. Striking progress has been particularly evident in Drosophila, whose extensive toolkit of mutants and transgenic lines provides a convenient model to study evolutionarily-conserved developmental and cell biological mechanisms. We are interested in understanding the mechanisms that control cell fate specification in the adult peripheral nervous system (PNS) in Drosophila. Bristles that cover the head, thorax, abdomen, legs and wings of the adult fly are individual mechanosensory organs, and have been studied as a model system for understanding mechanisms of Notch-dependent cell fate decisions. Sensory organ precursor (SOP) cells of the microchaetes (or small bristles), are distributed throughout the epithelium of the pupal thorax, and are specified during the first 12 hours after the onset of pupariation. After specification, the SOP cells begin to divide, segregating the cell fate determinant Numb to one daughter cell during mitosis. Numb functions as a cell-autonomous inhibitor of the Notch signaling pathway.
Here, we show a method to follow protein dynamics in SOP cell and its progeny within the intact pupal thorax using a combination of tissue-specific Gal4 drivers and GFP-tagged fusion proteins 1,2.This technique has the advantage over fixed tissue or cultured explants because it allows us to follow the entire development of an organ from specification of the neural precursor to growth and terminal differentiation of the organ. We can therefore directly correlate changes in cell behavior to changes in terminal differentiation. Moreover, we can combine the live imaging technique with mosaic analysis with a repressible cell marker (MARCM) system to assess the dynamics of tagged proteins in mitotic SOPs under mutant or wildtype conditions. Using this technique, we and others have revealed novel insights into regulation of asymmetric cell division and the control of Notch signaling activation in SOP cells (examples include references 1-6,7 ,8).

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

In this video, we describe a method for live cell imaging of asymmetrically dividing sensory organ progenitor cells and epidermal cells in intact Drosophila pupae

Live-Cell-Imaging von Sinnesorgan Vorläuferzellen im Intact Drosophila Puppen

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 ...

Single-cell Profiling of Developing and Mature Retinal Neurons

Highly specialized, but exceedingly small populations of cells play important roles in many tissues. The identification of cell-type specific markers and gene expression programs for extremely rare cell subsets has been a challenge using standard whole-tissue approaches. Gene expression profiling of individual cells allows for unprecedented access to cell types that comprise only a small percentage of the total tissue1-7. In addition, this technique can be used to examine the gene expression programs that are transiently expressed in small numbers of cells during dynamic developmental transitions8.
This issue of cellular diversity arises repeatedly in the central nervous system (CNS) where neuronal connections can occur between quite diverse cells9. The exact number of distinct cell types is not precisely known, but it has been estimated that there may be as many as 1000 different types in the cortex itself10. The function(s) of complex neural circuits may rely on some of the rare neuronal types and the genes they express. By identifying new markers and helping to molecularly classify different neurons, the single-cell approach is particularly useful in the analysis of cell types in the nervous system. It may also help to elucidate mechanisms of neural development by identifying differentially expressed genes and gene pathways during early stages of neuronal progenitor development.
As a simple, easily accessed tissue with considerable neuronal diversity, the vertebrate retina is an excellent model system for studying the processes of cellular development, neuronal differentiation and neuronal diversification. However, as in other parts of the CNS, this cellular diversity can present a problem for determining the genetic pathways that drive retinal progenitors to adopt a specific cell fate, especially given that rod photoreceptors make up the majority of the total retinal cell population11. Here we report a method for the identification of the transcripts expressed in single retinal cells (Figure 1). The single-cell profiling technique allows for the assessment of the amount of heterogeneity present within different cellular populations of the retina2,4,5,12. In addition, this method has revealed a host of new candidate genes that may play role(s) in the cell fate decision-making processes that occur in subsets of retinal progenitor cells8. With some simple adjustments to the protocol, this technique can be utilized for many different tissues and cell types.

A method for the isolation of single retinal cells and subsequent amplification of their cDNAs is described. Single-cell transcriptomics reveals the degree of cellular heterogeneity present in a tissue and uncovers new marker genes for rare cell populations. The accompanying protocol can be adjusted to suit many different cell types.

Einzel-Zell-Profiling der Entwicklung und Reife Netzhautneuronen

Highly specialized, but exceedingly small populations of cells play important roles in many tissues. The identification of cell-type specific markers and ...

Viral Tracing of Genetically Defined Neural Circuitry

Classical methods for studying neuronal circuits are fairly low throughput. Transsynaptic viruses, particularly the pseudorabies (PRV) and rabies virus (RABV), and more recently vesicular stomatitis virus (VSV), for studying circuitry, is becoming increasingly popular. These higher throughput methods use viruses that transmit between neurons in either the anterograde or retrograde direction.
Recently, a modified RABV for monosynaptic retrograde tracing was developed. (Figure 1A). In this method, the glycoprotein (G) gene is deleted from the viral genome, and resupplied only in targeted neurons. Infection specificity is achieved by substituting a chimeric G, composed of the extracellular domain of the ASLV-A glycoprotein and the cytoplasmic domain of the RABV-G (A/RG), for the normal RABV-G1. This chimeric G specifically infects cells expressing the TVA receptor1. The gene encoding TVA can been delivered by various methods2-8. Following RABV-G infection of a TVA-expressing neuron, the RABV can transmit to other, synaptically connected neurons in a retrograde direction by nature of its own G which was co-delivered with the TVA receptor. This technique labels a relatively large number of inputs (5-10%)2 onto a defined cell type, providing a sampling of all of the inputs onto a defined starter cell type.
We recently modified this technique to use VSV as a transsynaptic tracer9. VSV has several advantages, including the rapidity of gene expression. Here we detail a new viral tracing system using VSV useful for probing microcircuitry with increased resolution. While the original published strategies by Wickersham et al.4 and Beier et al.9 permit labeling of any neurons that project onto initially-infected TVA-expressing-cells, here VSV was engineered to transmit only to TVA-expressing cells (Figure 1B). The virus is first pseudotyped with RABV-G to permit infection of neurons downstream of TVA-expressing neurons. After infecting this first population of cells, the virus released can only infect TVA-expressing cells. Because the transsynaptic viral spread is limited to TVA-expressing cells, presence of absence of connectivity from defined cell types can be explored with high resolution. An experimental flow chart of these experiments is shown in Figure 2. Here we show a model circuit, that of direction-selectivity in the mouse retina. We examine the connectivity of starburst amacrine cells (SACs) to retinal ganglion cells (RGCs).

A method of tracing synaptically connected neurons is described. We use TVA specificity of an upstream cell to probe whether a cell population of interest receives synaptic input from genetically defined cell types.

Viral Tracing von genetisch definierten Neural Circuitry

Classical methods for studying neuronal circuits are fairly low throughput. Transsynaptic viruses, particularly the pseudorabies (PRV) and rabies virus ...

Implementing Dynamic Clamp with Synaptic and Artificial Conductances in Mouse Retinal Ganglion Cells

Ganglion cells are the output neurons of the retina and their activity reflects the integration of multiple synaptic inputs arising from specific neural circuits. Patch clamp techniques, in voltage clamp and current clamp configurations, are commonly used to study the physiological properties of neurons and to characterize their synaptic inputs. Although the application of these techniques is highly informative, they pose various limitations. For example, it is difficult to quantify how the precise interactions of excitatory and inhibitory inputs determine response output. To address this issue, we used a modified current clamp technique, dynamic clamp, also called conductance clamp 1, 2, 3 and examined the impact of excitatory and inhibitory synaptic inputs on neuronal excitability. This technique requires the injection of current into the cell and is dependent on the real-time feedback of its membrane potential at that time. The injected current is calculated from predetermined excitatory and inhibitory synaptic conductances, their reversal potentials and the cell's instantaneous membrane potential. Details on the experimental procedures, patch clamping cells to achieve a whole-cell configuration and employment of the dynamic clamp technique are illustrated in this video article. Here, we show the responses of mouse retinal ganglion cells to various conductance waveforms obtained from physiological experiments in control conditions or in the presence of drugs. Furthermore, we show the use of artificial excitatory and inhibitory conductances generated using alpha functions to investigate the responses of the cells.

This video article illustrates the set-up, the procedures to patch cell bodies and how to implement dynamic clamp recordings from ganglion cells in whole-mount mouse retinae. This technique allows the investigation of the precise contribution of excitatory and inhibitory synaptic inputs, and their relative magnitude and timing to neuronal spiking.

Implementieren Dynamische Clamp mit Synaptic und künstliche Leitfähigkeiten in Maus retinalen Ganglienzellen

Ganglion cells are the output neurons of the  retina and their activity reflects the integration of multiple synaptic inputs  arising from specific neural ...

Retrograde Labeling of Retinal Ganglion Cells in Adult Zebrafish with Fluorescent Dyes

As retrograde labeling retinal ganglion cells (RGCs) can isolate RGCs somata from dying sites, it has become the gold standard for counting RGCs in RGCs survival and regeneration experiments. Many studies have been performed in mammalian animals to research RGCs survival after optic nerve injury. However, retrograde labeling of RGCs in adult zebrafish has not yet been reported, though some alternative methods can count cell numbers in retinal ganglion cell layers (RGCL). Considering the small size of the adult zebrafish skull and the high risk of death after drilling on the skull, we open the skull with the help of acid-etching and seal the hole with a light curing bond, which could significantly improve the survival rate. After absorbing the dyes for 5 days, almost all the RGCs are labeled. As this method does not need to transect the optic nerve, it is irreplaceable in the research of RGCs survival after optic nerve crush in adult zebrafish. Here, we introduce this method step by step and provide representative results.

We introduce an efficient method to retrograde label retinal ganglion cells (RGCs) in adult zebrafish.

Retrograde Markierung von retinalen Ganglienzellen im erwachsenen Zebrafisch mit Fluoreszenzfarbstoffen

As retrograde labeling retinal ganglion cells (RGCs) can isolate RGCs somata from dying sites, it has become the gold standard for counting RGCs in RGCs ...

RNA-Seq Analysis of Differential Gene Expression in Electroporated Chick Embryonic Spinal Cord

In ovo electroporation of the chick neural tube is a fast and inexpensive method for identification of gene function during neural development. Genome wide analysis of differentially expressed transcripts after such an experimental manipulation has the potential to uncover an almost complete picture of the downstream effects caused by the transfected construct. This work describes a simple method for comparing transcriptomes from samples of transfected embryonic spinal cords comprising all steps between electroporation and identification of differentially expressed transcripts. The first stage consists of guidelines for electroporation and instructions for dissection of transfected spinal cord halves from HH23 embryos in ribonuclease-free environment and extraction of high-quality RNA samples suitable for transcriptome sequencing. The next stage is that of bioinformatic analysis with general guidelines for filtering and comparison of RNA-Seq datasets in the Galaxy public server, which eliminates the need of a local computational structure for small to medium scale experiments. The representative results show that the dissection methods generate high quality RNA samples and that the transcriptomes obtained from two control samples are essentially the same, an important requirement for detection of differential expression genes in experimental samples. Furthermore, one example is provided where experimental overexpression of a DNA construct can be visually verified after comparison with control samples. The application of this method may be a powerful tool to facilitate new discoveries on the function of neural factors involved in spinal cord early development.

This video shows the basic steps for performing whole transcriptome analysis on dissected chick embryonic spinal cord samples after transfection with in ovo electroporation.

RNA-Seq Analyse der differentiellen Genexpression in elektroporiertem Küken Embryonale Spinal Cord

In ovo electroporation of the chick neural tube is a fast and inexpensive method for identification of gene function during neural development. Genome ...

Optical Coherence Tomography: Imaging Mouse Retinal Ganglion Cells In Vivo

Structural changes in the retina are common manifestations of ophthalmic diseases. Optical coherence tomography (OCT) enables their identification in vivo&#8212;rapidly, repetitively, and at a high resolution. This protocol describes OCT imaging in the mouse retina as a powerful tool to study optic neuropathies (OPN). The OCT system is an interferometry-based, non-invasive alternative to common post mortem histological assays. It provides a fast and accurate assessment of retinal thickness, allowing the possibility to track changes, such as retinal thinning or thickening. We present the imaging process and analysis with the example of the Opa1delTTAG mouse line. Three types of scans are proposed, with two quantification methods: standard and homemade calipers. The latter is best for use on the peripapillary retina during radial scans; being more precise, is preferable for analyzing thinner structures. All approaches described here are designed for retinal ganglion cells (RGC) but are easily adaptable to other cell populations. In conclusion, OCT is efficient in mouse model phenotyping and has the potential to be used for the reliable evaluation of therapeutic interventions.

Optical Coherence Tomography: Imaging Mouse Retinal Ganglion Cells In Vivo

This manuscript describes a protocol for the in vivo imaging of the mouse retina with high-resolution spectral domain optical coherence tomography (SD-OCT). It focuses on retinal ganglion cells (RGC) in the peripapillary region, with several scanning and quantifying approaches described.

Optische Kohärenztomographie: Maus retinalen Ganglienzellen Zellen In Vivo Imaging

Structural changes in the retina are common manifestations of ophthalmic diseases. Optical coherence tomography (OCT) enables their identification in ...