Name: selection-dependent and independent generation of crispr/cas9-mediated gene knockouts in mammalian cells
Uploaded: 2017-06-16T15:00:00
Description: Watch this Scientific Journal Video about Selection-dependent and Independent Generation of CRISPR/Cas9-mediated Gene Knockouts in Mammalian Cells at JoVE.com

Die Autoren möchten Gissell Sanchez, Megan Lee und Jason Estep für experimentelle Hilfe und Weifeng Gu und Xuemei Chen für den Austausch von Reagenzien anerkennen.

1. Identifizierung von Homologieregionen um die gewünschte Löschung HINWEIS: Nur bei selektionsbasierter Bearbeitung erforderlich. <ol><li> Wähle zwei Regionen, anfänglich 1,5-2 kb, auf beiden Seiten des gewünschten Löschorts, die als Homologiearme in der HDR-Schablone dienen (Abbildung 1A ). Identifizieren Sie Regionen, die BsaI-Erkennungsstellen auf beiden Strang (GGTCTC) fehlen, um das Klonen zu erleichtern. Wenn BsaI-Stellen unvermeidbar sind, verwen...

<ol>
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Das CRISPR / Cas9-System ermöglicht eine effiziente Erzeugung stabiler genomischer Modifikationen, die eine konsistentere Alternative zu anderen transienten Manipulationsverfahren bieten. Hier haben wir zwei Methoden zur schnellen Identifizierung von CRISPR / Cas9-Gen-Knockouts in Säugetierzelllinien vorgestellt. Beide Methoden erfordern wenig zelluläres Material, so dass Tests in frühen Stadien der Klonalkultur durchgeführt werden können, spart Zeit und Reagenzien. Um die Effizienz beider Methoden zu erhöhen, em...

<html> Stabile genetische Veränderungen bieten einen Vorteil gegenüber transienten Methoden der zellulären Störung, die in ihrer Effizienz und Dauer variabel sein können. Die genomische Bearbeitung ist in den letzten Jahren aufgrund der Entwicklung von zielspezifischen Nukleasen, wie z. B. Zinkfinger-Nukleasen 1 , 2 , 3 , 4 , 5 , Transkriptionsaktivator-ähnliche Effektor-Nukleasen (TALENs) 6 , 7 , 8 , 9 immer häufiger geworden Und RNA-geführte Nukleasen, die aus dem geclusterten, regelmäßig verteilten kurzen palindromischen Wiederholungssystem (CRISPR) 10 gewonnen wurden . Die CRISPR / Cas9-Bearbeitungsmaschinen werden von einem Immunsystem angepasst, das Bakterien und Archaea zur Verteidigung gegen Virusinfektionen verwendenAss = &quot;xref&quot;&gt; 11 , 12 , 13 . In diesem Prozess werden kurze, 20-30 nt-Fragmente der eindringenden Virussequenz in einen genomischen Locus als &quot;Spacer&quot; eingebaut, die von den Wiederholungseinheiten 14 , 15 flankiert sind. Nachfolgende Transkriptions- und RNA-Verarbeitung erzeugt kleine CRISPR-assoziierte RNAs 16 (crRNAs), die zusammen mit einer transaktivierenden crRNA 17 (tracrRNA) mit der Effektor-Cas9-Endonuklease zusammensetzen. Die crRNAs bieten somit eine Spezifität für das Cas9-Targeting, die den Komplex leitet, um komplementäre virale DNA-Sequenzen zu spalten und weitere Infektionen zu verhindern 18 , 19 . Jede &quot;Protospacer&quot; -Sequenz in der Ziel-DNA kann als Quelle der crRNA dienen, solange sie direkt 5 &#39;zu einem kurzen Protospacer benachbarten Motiv (PAM), NGG im Fall von S. pyogenes Cas9 ist <sUp class = &quot;xref&quot;&gt; 20 Die Abwesenheit der PAM-Sequenz nahe dem Spacer im CRISPR-Locus des Hosts unterscheidet zwischen Selbst und Nicht-Selbst und verhindert das Targeting des Hosts. Wegen seiner Universalität und Flexibilität ist dieses biologische System mächtig für die genomische Bearbeitung angepasst worden, so dass nahezu jede PAM-benachbarte DNA-Stelle gezielt werden kann. In dieser Version fusionierte eine weitere Modifikation die crRNA und tracrRNA zu einer einzigen RNA (sgRNA) -Komponente, die in das Cas9-Protein 21 geladen wurde. Bei der Expression von Cas9 und einer sgRNA in eukaryotischen Zellen spaltet das Cas9-Protein beide DNA-Stränge am Zielort. In Abwesenheit einer geeigneten Region der homologen Sequenz fixiert die Zelle diesen Bruch über eine nicht homologe Endverbindung (NHEJ) 22 , 23 , 24 , die typischerweise kleine Deletionen oder selten Insertionen einführt. Bei der Ausrichtung auf eine offeneLeserahmen, führt die Reparatur wahrscheinlich zu einer translationalen Frameshift, die ein nicht-funktionelles Proteinprodukt produziert. Im Gegensatz dazu kann die Zelle, wenn sie mit einer exogenen Schablone mit großen Regionen der Homologie versehen ist, die doppelsträngige Pause durch homologisch gerichtete Reparatur 25 , 26 fixieren. Dieser Weg ermöglicht größere präzise Deletionen, Ersetzungen oder Insertionen im Genom, gepaart mit der Einführung von ausfahrbaren Selektionsmarkern 27 . Hier stellen wir Protokolle zur Erzeugung von Knockout-Zelllinien durch eine dieser beiden CRISPR / Cas9-Verfahren vor (Abbildung 1A ). Der NHEJ-Ansatz nutzt eine einzelne sgRNA-Cut-Site und selektionsunabhängiges Screening und erfordert daher eine geringe Vorwärtspräparation. Bei der Verwendung dieser Methode müssen RNAs, die komplementär zu Exons in der Nähe des 5&#39;-Endes des Transkripts sind, die am ehesten ein Knockout produzieren, entworfen werden. Seit dem modifikatIonen zum Genom in diesem Fall sind klein, das Screening auf Knockout-Klone basiert auf Punkt-Blots, wo das Protein-Produkt in einer Hochdurchsatz-Weise beurteilt wird. Wir verwenden die Generation von ELAV-ähnlichen 1 Protein (ELAVL1) Knockout Linien als Beispiel. Der zweite Ansatz beruht auf homologisch gerichteter Reparatur (HDR) und verwendet zwei sgRNA-Cut-Stellen, die das Gen oder die Region von Interesse überspannen, was eine Deletionen von zehn kb ermöglicht. Ein Plasmid mit zwei Regionen der Homologie, die die Spaltstellen flankieren, liefert eine Ersatzschablone (Abbildung 1B ), die einen wählbaren Resistenzmarker einführt, der die Effizienz der Knockout-Erzeugung erhöht. Diese Methode kann auch angepasst werden, um Genmodifikationen mit richtig entworfenen Homologiearmen einzuführen. In diesem Fall ermöglicht die Integration eines neuen DNA-Fragments ein PCR-basiertes Screening (Abbildung 1C ). Hier verwenden wir die Generierung von Pumilio RNA Bindung Familienmitglied 2 (PUM2) Knockout Linien als Beispiel.

<table border="0" cellpadding="0" cellspacing="0" width="740">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:227px;">Competent E. coli cells</td>
			<td style="width:95px;"></td>
			<td style="width:120px;"></td>
			<td style="width:299px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">plasmid prep kit</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">pSpCas9(BB) plasmid</td>
			<td>Addgene</td>
			<td>42230</td>
			<td>Ran et al 2013, cloning sgRNAs</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">BbsI enzyme</td>
			<td>ThermoFisher</td>
			<td>FD1014</td>
			<td>Ran et al 2013, cloning sgRNAs</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">T7 DNA ligase</td>
			<td>NEB</td>
			<td>M0318L</td>
			<td>Ran et al 2013, cloning sgRNAs</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Tango Buffer</td>
			<td>ThermoFisher</td>
			<td>BY5</td>
			<td>Ran et al 2013, cloning sgRNAs</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">PlasmidSafe exonuclease</td>
			<td>Epicentre</td>
			<td>E3105K</td>
			<td>Ran et al 2013, cloning sgRNAs</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Q5 hot start high fidelity polymerase</td>
			<td>NEB</td>
			<td>M0494A</td>
			<td>HA amplification</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">pUC19-BsaI</td>
			<td></td>
			<td></td>
			<td>Modified pUC19 plasmid, mutated existing BsaI site and inserted two outward facing BsaI sites after BamHI/EcoRI digestion</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">pGolden-Neo</td>
			<td>Addgene</td>
			<td>51422</td>
			<td>Resistance cassette</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">pGolden-Hygro</td>
			<td>Addgene</td>
			<td>51423</td>
			<td>Resistance cassette</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">BsaI enzyme</td>
			<td>NEB</td>
			<td>R3535S</td>
			<td>Homology arm contruction</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">T7 DNA ligase</td>
			<td>NEB</td>
			<td>M0318L</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">PlasmidSafe exonuclease</td>
			<td>Epicentre</td>
			<td>E3105K</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Toothpicks</td>
			<td></td>
			<td></td>
			<td>bacterial PCR</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Taq polymerase</td>
			<td></td>
			<td></td>
			<td>bacterial colony PCR</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">HEK293 human cells</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">DMEM</td>
			<td>Corning</td>
			<td>10-013-CV</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">FBS</td>
			<td>Corning</td>
			<td>MT35010CV</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Penicillin-Strep (opt.)</td>
			<td>Gibco</td>
			<td>15140-122</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">6 well plates</td>
			<td>BioLite</td>
			<td>12556004</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">TransIT-LTI Transfection Reagent</td>
			<td>Mirus</td>
			<td>MIR2300</td>
			<td>for lipofection only</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Opti-MEM</td>
			<td>ThermoFisher</td>
			<td>31985062</td>
			<td>for lipofection only</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">G418 (Neomycin)</td>
			<td>Sigma Aldrich</td>
			<td>A1720-5G</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hygromycin</td>
			<td>Sigma Aldrich</td>
			<td>H3274-250MG</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">96 well plates</td>
			<td>ThermoFisher</td>
			<td>12556008</td>
			<td></td>
		</tr>
		<tr height="18">
			<td height="18" style="height:18px;">Passive Lysis Buffer, 5x</td>
			<td>Promega</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="18">
			<td height="18" style="height:18px;">1xSDS loading buffer</td>
			<td></td>
			<td></td>
			<td>recipe decribed in protocol</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Nitrocellulose Membrane</td>
			<td>Bio-Rad</td>
			<td>162-0115</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">TBST</td>
			<td></td>
			<td></td>
			<td>recipe decribed in protocol</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Dehydrated milk</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">SuperSignal West Dura Extended Duration Substrate</td>
			<td>ThermoFisher</td>
			<td>34075</td>
			<td>for HRP-conjugated secondary antibodies</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Extracta DNA prep for PCR</td>
			<td>Quantabio</td>
			<td>95091-025</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">KOD polymerase</td>
			<td>Novagen</td>
			<td>71316</td>
			<td></td>
		</tr>
	</tbody>
</table>

selection-dependent and independent generation of crispr/cas9-mediated gene knockouts in mammalian cells

Das CRISPR / Cas9 Genom Engineering System hat die Biologie revolutioniert, indem es genaue Genombearbeitung mit wenig Aufwand ermöglicht. Geleitet von einer einzigen Guide-RNA (sgRNA), die Spezifität verleiht, spaltet das Cas9-Protein beide DNA-Stränge am Zielort. Der DNA-Bruch kann entweder nicht-homologe Endverbindungen (NHEJ) oder Homologie gerichtete Reparatur (HDR) auslösen. NHEJ kann kleine Deletionen oder Insertionen einführen, die zu Frame-Shift-Mutationen führen, während HDR größere und präzisere Störungen ermöglicht. Hier präsentieren wir Protokolle zur Erzeugung von Knockout-Zelllinien durch Kopplung von etablierten CRISPR / Cas9-Methoden mit zwei Optionen für die nachgeschaltete Auswahl / Screening. Der NHEJ-Ansatz nutzt eine einzelne sgRNA-Cut-Stelle und selektionsunabhängiges Screening, bei der die Proteinproduktion durch Dot-Immunoblot in einer Hochdurchsatz-Weise beurteilt wird. Der HDR-Ansatz verwendet zwei sgRNA-Cut-Stellen, die das Gen von Interesse überspannen. Zusammen mit einer bereitgestellten HDR-Vorlage kann diese Methode eine Löschung erreichenVon zehn kb, unterstützt durch die eingefügte wählbare Widerstandsmarkierung. Die entsprechenden Anwendungen und Vorteile jeder Methode werden diskutiert.

Für die Erzeugung von ELAVL1-Knockout-Linien war ein robuster Antikörper verfügbar, so dass die Bearbeitung mit einzelnen sgRNAs (Abbildung 1A , links) durchgeführt wurde, gefolgt von Punkt-Immunoblot. Drei sgRNAs wurden unabhängig transfiziert, um die Effizienz zu vergleichen und die Ziel-Effekte in den resultierenden Klonen auszuschließen. Nach dem Sammeln und Blotting von Zelllysaten aus klonalen Populationen auf zwei Nitrozellulosemembranen wurden ...

Watch this Scientific Journal Video about Selection-dependent and Independent Generation of CRISPR/Cas9-mediated Gene Knockouts in Mammalian Cells at JoVE.com

Selection-dependent and Independent Generation of CRISPR/Cas9-mediated Gene Knockouts in Mammalian Cells

Jüngste Fortschritte in der Fähigkeit, somatische Zelllinien genetisch zu manipulieren, haben großes Potenzial für grundlegende und angewandte Forschung. Hier präsentieren wir zwei Ansätze für CRISPR / Cas9-produzierte Knockout-Produktion und Screening in Säugetierzelllinien, mit und ohne Verwendung von selektierbaren Markern.

Selektionsabhängige und unabhängige Erzeugung von CRISPR / Cas9-vermittelten Gen-Knockouts in Säugetierzellen

The CRISPR/Cas9 genome engineering system has revolutionized biology by allowing for precise genome editing with little effort. Guided by a single guide ...

The goal of this procedure is to isolate and identify clonal knockout cell lines generated by two types of CRIPSR/Cas9-mediated genome editing. One method detects protein knockout caused by nonhomologous end joining while the other detects genomic perturbations generated by homology-directed repair. This method is particularly useful in the field of molecular biology, where generation of cell lines with genetic perturbations is an important tool in dissecting gene function.The main advantage of this technique is that it is a quick and relatively high-throughput method that can be easily executed using basic molecular biology techniques. Nonhomologous end joining introduces small deletions or insertions, and are assessed by a dot immunoblot, while homology-directed repair allows for larger and more precise perturbations, and are assessed by colony PCR. This experiment uses T-REx-293 cells cultured in DMEM media, supplemented with 10%FBS at 37 degrees Celsius, and 5%carbon dioxide.Prior to transvection, plate the cells onto six well plates and include a well for an untransvected control. Grow the cells to approximately 70%confluency. Transvect the cells with 2.5 micrograms of total plasmid using a commercial transvection protocol.For transvection of cells without selection, use 2.5 micrograms of Cas9-sgRNA plasmid. For transvection of cells with selection, use 0.75 micrograms of Cas9-sgRNA1, 0.75 micrograms of Cas9-sgRNA2, and one microgram of homologous recombination template. Incubate the transvected cells and the untransvected control at 37 degrees Celsius and 5%carbon dioxide for 48 hours.For cells transvected with selection, begin the drug selection by treating the cells with the appropriate drug, which is Neomycin in this case. Return the six-well plate to the incubator. Observe the treated cells once a day to check for rates of cell death, until all cells in the untransvected control die.To isolate clonal populations, first grow the cells to 100%confluency in the original well after selection. Next make serial dilutions of the cells and count the cells. Since the proper generation of monoclonal colonies is key to obtaining a full knockout, care must be taken to determine the correct dilution for seating cells at the desired density.Once the correct dilution has been determined, seat the cells into 96-well plates at a density of 0.33 cells per well. Seating three 96=well plates is a good starting point to ensure isolation of more than one correct clone. Over a two-to-four week period, observe the colonies until colonies are visible to the eye.These representative images show colonies at different stages of growth. A single cell at seating, cells at day five, and a well-established colony at day 10. Using a sterile pipette tip, pick visible colonies with care and precision, and reseat in new wells to encourage monolayer growth.Continue growing the cells at 37 degrees Celsius and 5%carbon dioxide. Knockout candidates without selection are screened by dot immunoblot to assess the protein product in a high-throughput manner. After growing individual clones to 50 to 100%confluency, dislodge the monolayer of cells by pipetting within the well.Aliquot 90 microliters of the 100 microliter total volume from each well to a clean microcentrifuge tube. For the purposes of this video, only two samples will be processed. Spin down at 6, 000 RPM for five minutes, remove the media, and lyse the cell pallet in 10 microliters of 1X SDS loading buffer.Add 90 microliters of new media to the remainder of the cells in the well, and return the plate to the incubator to continue propagating the cells. Pipette one microliter of cell lysate onto a dry nitrocellulose membrane to form a dot. Blot each sample twice on two separate membranes, creating two identical patterns of samples.Block the membranes in 5%milk in TBST at room temperature, with rocking, for one hour. After one hour, blot the membranes with primary antibodies at the recommended primary antibody dilution, and TBST plus 5%milk. On one membrane use the primary antibody against the target protein, ELAVL1 in this experiment.On the other membrane, use the primary antibody for a control protein that is not expected to change, PUM2 is used here. Incubate at room temperature for one hour. Remove the primary antibody solution from each blot, add TBST, and incubate for five minutes.In this manner, wash the blots three times with TBST. Next, add to each membrane the appropriate HRP conjugated secondary antibody, and blot at room temperature for one hour. After one hour, wash the membranes three times with TBST for five minutes each time.Apply a chemiluminescent substrate solution to the blots, following the manufacturer's instructions, and image the blotted membranes on a digital chemiluminescence imager. Lastly, quantify dot intensities for the target and control proteins using the appropriate software, and analyze the results as described in the text protocol. Candidates with the selectable resistance marker are screened by colony PCR.Begin this procedure by duplicating individual colonies in a new 96-well plate, and growing them to 100%confluency for preparation of cell lysates. Remove the media from one set of the clones, resuspend the cells from each well in 30 microliters of extraction buffer from a commercial DNA preparation kit, and transfer to a clean 1.5 milliliter microcentrifuge tube. Heat the solution to 96 degrees Celsius for 15 minutes, and then let cool to room temperature.Add 30 microliters of stabilization buffer to each microcentrifuge tube and mix well. To identify wild-type and monoallelic or biallelic mutant lines by colony PCR, design two separate sets of PCR primers to amplify regions around the homology arms based on either successful or unsuccessful integration of the resistance cassette. On each side, use a common primer that anneals outside of the homology arm.To test for the wild-type allele, use the common primer with the corresponding paired primer that is complementary to the endogenous sequence spanning the homology region. To test for the desired mutation, use the common primer with another paired primer, complementary to the inserted resistance cassette. For each sample to be tested, prepare a reaction mixture containing the following, 0.5 microliters of cell lysate, 1.25 microliters of 10X KOD buffer, 0.75 microliters of 25 millimolar magnesium sulfate, 1.25 microliters of two millimolar dNTPs, 0.375 microliters of forward primer, 0.375 microliters of reverse primer, 0.25 microliters of KOD polymerase, and 7.75 microliters of water.Perform PCR using the following conditions, 95 degrees Celsius for two minutes, followed by 25 cycles of 95 degree Celsius for 20 seconds, primer melting temperature for 10 seconds, and 70 degrees Celsius for 20 seconds per KB.Subsequently, visualize the PCR products by agarose gel electrophoresis. Genome editing using non-homologous end joining was performed to generate ELAVL1 knockout lines followed by dot immunoblot, probing for ELAVL1 and PUM2. Clones that displayed little control signal were marked with an X, and excluded from further analysis.Clones with low ELAVL1 signals were further tested by western blot. Confirmed candidates are indicated in green, and invalidated candidates are indicated in gray. This graphic shows the ratios of ELAVL1 to control protein signal in increasing order.In most cases, clonal populations with the lowest relative ELAVL1 signal were correctly identified as knockouts. Candidates generated by the homology directed repair method were screened by colony PCR, and the PCR products visualized by agarose gel electrophoresis. Shown are example results using primers spanning the upstream integration junction using endogenous inside primers and knockout inside primers.Primers were first validated in both parental cells and bulk selected cells. Results from 24 individual candidate clones are shown together with the expected band patters for wild-type, knockout, and monoallelic deletion clones. The black arrows indicate the correct amplification products, stars indicate biallelic knockout clones.The biallelic mutant lines were further validated by western blot. Nonhomologous end joining uses a single Cas9 cut and selection-independent screening, thus requiring little up-front preparation, and screening for knockout clones by dot blots can quickly determine if a knockout generation was successful. PCR-based screening accurately detects correct candidates with large genomic perturbations generated by homology-directed repair.These techniques enable researchers in molecular biology to easily and efficiently identify knockouts, allowing them to explore normal or dysfunctional cellular processes using cell lines. After watching this video, you should have a good understanding of how to isolate and identify clonal knockout cell lines generated by CRISPR/Cas9 mediated genome editing.

Research

JoVE Journal

Genetics

Rearing and Double-stranded RNA-mediated Gene Knockdown in the Hide Beetle, Dermestes maculatus

Rearing and Double-stranded RNA-mediated Gene Knockdown in the Hide Beetle, Dermestes maculatus

Zucht- und RNA-vermittelte Gene Knockdown in der ausblenden Doppelstrang-Käfer,<em&gt; Dermestes maculatus</em

Advances in genomics have raised the possibility of probing biodiversity at an unprecedented scale. However, sequence alone will not be informative ...

Forschung

Genetik

Using a Fluorescent PCR-capillary Gel Electrophoresis Technique to Genotype CRISPR/Cas9-mediated Knockout Mutants in a High-throughput Format

Mit Hilfe eines Fluoreszenz-PCR-Kapillar-Gel-Elektrophorese-Technik CRISPR zum Genotyp / Cas9 vermittelte Knock-out Mutanten in einem Hochdurchsatz-Format

The development of programmable genome-editing tools has facilitated the use of reverse genetics to understand the roles specific genomic sequences play ...

A Standard Methodology to Examine On-site Mutagenicity As a Function of Point Mutation Repair Catalyzed by CRISPR/Cas9 and SsODN in Human Cells

Eine Standardmethodik, vor-Ort-Mutagenität als Funktion der Punktmutation Reparatur katalysiert durch CRISPR/Cas9 und SsODN in den menschlichen Zellen zu untersuchen

Combinatorial gene editing using CRISPR/Cas9 and single-stranded oligonucleotides is an effective strategy for the correction of single-base point ...

Generation of a Gene-disrupted Streptococcus mutans Strain Without Gene Cloning

Generation of a Gene-disrupted Streptococcus mutans Strain Without Gene Cloning

Generation von einem Gen gestört Streptococcus Mutans Belastung ohne Gene Klonen

Typical methods for the elucidation of the function of a particular gene involve comparative phenotypic analyses of the wild-type strain and a strain in ...

CRISPR/Cas9-mediated Targeted Integration In Vivo Using a Homology-mediated End Joining-based Strategy

CRISPR/Cas9-mediated Targeted Integration In Vivo Using a Homology-mediated End Joining-based Strategy

CRISPR/Cas9-vermittelten gezielte Integration In Vivo mit einer Homologie-vermittelte Ende verbinden-basierte Strategie

As a promising genome editing platform, the CRISPR/Cas9 system has great potential for efficient genetic manipulation, especially for targeted integration ...

A Protocol for the Production of Integrase-deficient Lentiviral Vectors for CRISPR/Cas9-mediated Gene Knockout in Dividing Cells

Ein Protokoll für die Produktion der Integrase-defizienten Lentivirale Vektoren für CRISPR/Cas9-vermittelte Gen Knockout in teilenden Zellen

Lentiviral vectors are an ideal choice for delivering gene-editing components to cells due to their capacity for stably transducing a broad range of cells ...

Efficient Production and Identification of CRISPR/Cas9-generated Gene Knockouts in the Model System Danio rerio

Efficient Production and Identification of CRISPR/Cas9-generated Gene Knockouts in the Model System Danio rerio

Effiziente Produktion und Kennzeichnung der CRISPR/Cas9 generiert gen Knockouts im Modellsystem Danio rerio

Characterization of the clustered, regularly interspaced, short, palindromic repeat (CRISPR) system of Streptococcus pyogenes has enabled the development ...

Adaptation of Hybridization Capture of Chromatin-associated Proteins for Proteomics to Mammalian Cells

Anpassung der Hybridisierung erfassen der Chromatin-assoziierte Proteine für Proteomics für Säugerzellen

The hybridization capture of chromatin-associated proteins for proteomics (HyCCAPP) technology was initially developed to uncover novel DNA-protein ...

Formaldehyde-assisted Isolation of Regulatory Elements to Measure Chromatin Accessibility in Mammalian Cells

Formaldehyd-gestützte Isolation regulatorischer Elemente auf die Maßnahme Chromatin Barrierefreiheit in Säugerzellen

Appropriate gene expression in response to extracellular cues, that is, tissue- and lineage-specific gene transcription, critically depends on highly ...

Highly Efficient Gene Disruption of Murine and Human Hematopoietic Progenitor Cells by CRISPR/Cas9

Hocheffiziente gen Störung der murinen und menschlichen hämatopoetischen Vorläuferzellen von CRISPR/Cas9

Advances in the hematopoietic stem cell (HSCs) field have been aided by methods to genetically engineer primary progenitor cells as well as animal models. ...