Name: pooled shrna screen for reactivation of mecp2 on the inactive x chromosome
Uploaded: 2018-03-02T13:00:00
Description: Watch this Scientific Journal Video about Pooled shRNA Screen for Reactivation of MeCP2 on the Inactive X Chromosome at JoVE.com

Wir bedanken uns bei Ross Dickins von der University of Melbourne für die Bereitstellung von gnädig der ShRNA-Bibliothek auf dem Bildschirm verwendet. Diese Arbeit wurde durch die Rett Syndrome Research Trust (A.B) finanziert.

Alle Schritte, bei denen Tiere wurden durchgeführt mit Protokollen vom Fred Hutchinson Cancer Research Center institutionelle Animal Care und Nutzung Committee (IACUC) genehmigt. Keine Reagenzien hier bekanntermaßen erhebliche menschliche Gesundheitsrisiken außer 5-Azacytidine (5-AZA) darstellen.
1. erzeugen eine Reporter-Zell-Linie mit MeCP2- LUC-HR Transgen auf der Xi
<ol><li>
Vorbereitung der Maus Sehne Fibroblasten von einer Frau XMeCP2-LUC- HR/xMeCP2<...

<ol>
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A., Galloway, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+papillomavirus+type+16+E7+alleviates+a+proliferation+block+in+early+passage+human+mammary+epithelial+cells.">Human papillomavirus type 16 E7 alleviates a proliferation block in early passage human mammary epithelial cells.</a> Oncogene. 12, 1773-1779 (1996).</li><li>Hnasko, T. S., Hnasko, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Western+Blot.">The Western Blot.</a> Methods Mol Biol. 1318, 87-96 (2015).</li><li>Strezoska, 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=Optimized+PCR+conditions+and+increased+shRNA+fold+representation+improve+reproducibility+of+pooled+shRNA+screens.">Optimized PCR conditions and increased shRNA fold representation improve reproducibility of pooled shRNA screens.</a> PLoS One. 7, e42341 (2012).</li><li>Green, M. R., Sambrook, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+of+High-Molecular-Weight+DNA+from+Mammalian+Tissues+Using+Proteinase+K+and+Phenol.">Isolation of High-Molecular-Weight DNA from Mammalian Tissues Using Proteinase K and Phenol.</a> Cold Spring Harb Protoc. 2017, (2017).</li><li>Goto, Y., Takagi, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tetraploid+embryos+rescue+embryonic+lethality+caused+by+an+additional+maternally+inherited+X+chromosome+in+the+mouse.">Tetraploid embryos rescue embryonic lethality caused by an additional maternally inherited X chromosome in the mouse.</a> Development. 125, 3353-3363 (1998).</li><li>Csankovszki, G., Nagy, A., Jaenisch, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synergism+of+Xist+RNA,+DNA+methylation,+and+histone+hypoacetylation+in+maintaining+X+chromosome+inactivation.">Synergism of Xist RNA, DNA methylation, and histone hypoacetylation in maintaining X chromosome inactivation.</a> J Cell Biol. 153, 773-784 (2001).</li><li>Minajigi, A., 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=Chromosomes.+A+comprehensive+Xist+interactome+reveals+cohesin+repulsion+and+an+RNA-directed+chromosome+conformation.">Chromosomes. A comprehensive Xist interactome reveals cohesin repulsion and an RNA-directed chromosome conformation.</a> Science. 349, (2015).</li><li>McHugh, C. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Xist+lncRNA+interacts+directly+with+SHARP+to+silence+transcription+through+HDAC3.">The Xist lncRNA interacts directly with SHARP to silence transcription through HDAC3.</a> Nature. 521, 232-236 (2015).</li><li>Bhatnagar, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+and+pharmacological+reactivation+of+the+mammalian+inactive+X+chromosome.">Genetic and pharmacological reactivation of the mammalian inactive X chromosome.</a> Proc Natl Acad Sci U S A. 111, 12591-12598 (2014).</li><li>Minkovsky, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Mbd1-Atf7ip-Setdb1+pathway+contributes+to+the+maintenance+of+X+chromosome+inactivation.">The Mbd1-Atf7ip-Setdb1 pathway contributes to the maintenance of X chromosome inactivation.</a> Epigenetics Chromatin. 7, 12 (2014).</li><li>Minkovsky, A., 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+high-throughput+screen+of+inactive+X+chromosome+reactivation+identifies+the+enhancement+of+DNA+demethylation+by+5-aza-2'-dC+upon+inhibition+of+ribonucleotide+reductase.">A high-throughput screen of inactive X chromosome reactivation identifies the enhancement of DNA demethylation by 5-aza-2'-dC upon inhibition of ribonucleotide reductase.</a> Epigenetics Chromatin. 8, 42 (2015).</li></ol>

In unserer letzten Studie6, erzielten wir eine murinen Zelllinie mit Luciferase und Hygromycin-Resistenz-Gene mit MeCP2 auf der Xi verschmolzen und mit einer Bibliothek von ausgestrahlt > 60.000 ShRNAs targeting > 25.000 Gene. Wir fanden 30 Gene deren Knock-down übertragenen Überlebensvorteil unter Hygromycin B-Auswahl, was ihre Rolle in der Steuerung von MeCP2 und X-Chromosom zum Schweigen zu bringen. Diese Ergebnisse wurden durch transducing die gemeldeten Zell-Linie mit einz...

Eine der häufigsten Formen der erblichen psychischen Beeinträchtigung bei Frauen, Rett-Syndrom, wird verursacht durch heterozygoten Mutationen im MeCP2, ein X-Chromosom-gen, das ein Protein wichtig für normale neuronale Funktion1kodiert. Eine mögliche Ansatz zur Behandlung dieser Erkrankung wäre Reaktivierung der Wildtyp MeCP2 Allel auf Xi, wie Wiederherstellung von MeCP2 Ausdruck zeigte umzukehrenden neurologische Defizite in einem Mausmodell der diese Krankheit1, 2 , 4. jedoch epigenetische silencing von einem der beiden X-Chromosomen in weiblichen Zellen fest bleibt, während der gesamten Lebensdauer eines Organismus3,4, und robuste Reaktivierung eines Gens Xi müsste wahrscheinlich a-Dur Störungen in mehreren epigenetische Regulierung Bahnen.
Ermittlung der Faktoren, die für Wartung von MeCP2 zum Schweigen zu bringen, haben wir zuerst entwickelt einem transgenen Mausmodell tragen eine MeCP2- Luciferase - Hygromycin Widerstand gen Fusion (MeCP2-LUC-HR) auf einem der beiden X-Chromosomen (X MeCP2-LUC-HR/xMeCP2)5. Obwohl die MeCP2 von Fusion Konstrukt ausgedrückt erwies sich als instabil und führte zu einem Verlust der Funktion, phänotypisch imitiert MeCP2 Löschung bei Hemizygous Männern (XMeCP2-LUC-HR/y), die Expression der Gene reporter war in einem Muster entsprechen der Ausdruck der endogenen MeCP25leicht nachweisbar. Wir dann verewigt Fibroblasten Klone mit dem Konstrukt auf entweder inaktiv oder aktiv X-Chromosom erzeugt, und bestätigte, dass der ehemalige Wildtyp MeCP2 und nicht das Reporter-Konstrukt zum Ausdruck gebracht; die Inverse galt für Letzteres. Wenn ein DNA-demethylating Agent bekannt, Gen-silencing, aufzuheben 5-Azacytidine (5-AZA) ausgesetzt gewonnen Zellen mit dem Reporter auf der Xi ("Reporter-Zellen") Aktivität in einem Biolumineszenz-Assay, darauf hinweist, dass unsere Konstrukt reaktiviert werden könnten und daher für genetisches Screening verwendet.
Wir entwickelt als nächstes einen Hochdurchsatz-genetischen Bildschirm für Regulatoren des MeCP2 zum Schweigen zu bringen. Die Reporter-Zell-Linie wurde zuerst mit einem antiretroviralen Bibliothek mit infiziert > 60.000 verschiedene ShRNAs targeting > 25.000 Gene in der Maus Genom5,6, und dann Hygromycin B Auswahl unterzogen. Haarnadel Frequenz verglich in Pre- und Post-Auswahl Proben mit Sequenzierung der nächsten Generation, als Reporter Reaktivierung Wachstum Vorteil unter Hygromycin B Auswahl und Anreicherung der Verantwortlichen Haarnadeln führte. Mit diesem Ansatz, wir 30 Gene verwickelt in MeCP2 zum Schweigen zu bringen und anschließend bestätigte die Ergebnisse von transducing die Reporter Zellen mit einzelnen Haarnadeln und Messung ihrer Luciferase-Aktivität.

<table>
	<tbody>
		<tr>
			<td>293FT Cell Line</td>
			<td>Invitrogen</td>
			<td>R700-07</td>
			<td></td>
		</tr>
		<tr>
			<td>5-Azacytidine</td>
			<td>Sigma</td>
			<td>A2385-100MG</td>
			<td></td>
		</tr>
		<tr>
			<td>Agencourt AMPure XP</td>
			<td>Beckman-Coulter</td>
			<td>A63881</td>
			<td></td>
		</tr>
		<tr>
			<td>Anti-MECP2 antibody</td>
			<td>Millipore</td>
			<td>07-013</td>
			<td></td>
		</tr>
		<tr>
			<td>Collagenase</td>
			<td>Sigma</td>
			<td>C2674-1G</td>
			<td></td>
		</tr>
		<tr>
			<td>Corning 96-Well Solid White Polystyrene Microplates</td>
			<td>Fisher Scientific</td>
			<td>07-200-336</td>
			<td></td>
		</tr>
		<tr>
			<td>Dulbecco&#39;s Modified Eagle Medium</td>
			<td>Gibco</td>
			<td>11965-092</td>
			<td></td>
		</tr>
		<tr>
			<td>Expression Arrest microRNA-adapted Retroviral Vector (pMSCV)</td>
			<td>Open Biosystems</td>
			<td>EAV4679</td>
			<td></td>
		</tr>
		<tr>
			<td>Expression Arrest pSM2 Retroviral shRNAmir library</td>
			<td>Open Biosystems</td>
			<td>RMM3796</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum</td>
			<td>Fisherbrand</td>
			<td>03-600-511</td>
			<td></td>
		</tr>
		<tr>
			<td>HiSeq 2500</td>
			<td>Illumina</td>
			<td>SY&#8211;401&#8211;2501</td>
			<td>Or equivalent</td>
		</tr>
		<tr>
			<td>Hygromycin B</td>
			<td>Calbiochem</td>
			<td>400051-1MU</td>
			<td></td>
		</tr>
		<tr>
			<td>Lipofectamine 2000</td>
			<td>Invitrogen</td>
			<td>11668-019</td>
			<td></td>
		</tr>
		<tr>
			<td>Bright-Glo Luciferase Assay System</td>
			<td>Promega</td>
			<td>E2610</td>
			<td>Homogenous Assay for Screening Colonies</td>
		</tr>
		<tr>
			<td>Luciferase Assay System</td>
			<td>Promega</td>
			<td>E4530</td>
			<td>Non-Homogenous Assay for Testing Individual Hairpins</td>
		</tr>
		<tr>
			<td>Luminometer TopCount NXT</td>
			<td>Perkin Elmer</td>
			<td>N/A</td>
			<td>Or similar luminometer</td>
		</tr>
		<tr>
			<td>MiSeq Reagent Kit v2</td>
			<td>Illumina</td>
			<td>MS-102-2001</td>
			<td>Use kit compatible with your equipment</td>
		</tr>
		<tr>
			<td>Opti-MEM</td>
			<td>Gibco</td>
			<td>31985-070</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin-Streptomycin</td>
			<td>Gibco</td>
			<td>15140-122</td>
			<td></td>
		</tr>
		<tr>
			<td>pMD2.G</td>
			<td>Addgene</td>
			<td>#12259</td>
			<td>VSV-G envelope vector</td>
		</tr>
		<tr>
			<td>Polybrene</td>
			<td>Sigma</td>
			<td>TR-1003-G</td>
			<td></td>
		</tr>
		<tr>
			<td>Polyethylenimine</td>
			<td>Polysciences</td>
			<td>23966-1</td>
			<td></td>
		</tr>
		<tr>
			<td>psPAX2</td>
			<td>Addgene</td>
			<td>#12260</td>
			<td>Packaging vector</td>
		</tr>
		<tr>
			<td>Puromycin</td>
			<td>Gibco</td>
			<td>A11138-02</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypsin-EDTA (0.05%), phenol red</td>
			<td>Gibco</td>
			<td>25300-054</td>
			<td></td>
		</tr>
	</tbody>
</table>

pooled shrna screen for reactivation of mecp2 on the inactive x chromosome

Nach vorne genetische Bildschirme mit Reporter-Gene in das Heterochromatin eingefügt wurden ausgiebig zur epigenetischen Kontrollmechanismen in Modellorganismen untersuchen. Technologien einschließlich kurze Haarnadel RNAs (ShRNAs) und gruppierten regelmäßig dazwischen kurze palindromische Wiederholungen (CRISPR) haben solche Bildschirme in diploiden Säugetier-Zellen aktiviert. Hier beschreiben wir einen groß angelegte ShRNA-Bildschirm für Regulatoren der X-Chromosom Inaktivierung (XCI), mit einem murinen Zelllinie mit Firefly Luciferase und Hygromycin-Resistenz-Gene klopfte am C-Terminus von Methyl CpG verbindliches Protein 2 (MeCP2) gen auf dem inaktiven X-Chromosom (Xi). Reaktivierung des Konstrukts in der Reporter-Zellinie übertragenen Überlebensvorteil unter Hygromycin B Auswahl ermöglicht uns eine große ShRNA-Bibliothek und Haarnadeln, die die Reporter reaktiviert durch Messen, ihre Post-Auswahl Bereicherung zu identifizieren Sequenzierung der nächsten Generation. Die angereicherten Haarnadeln wurden dann einzeln testen ihre Fähigkeit zur Aktivierung der Luciferase Reporters auf Xi validiert.

Maus Sehne Fibroblasten geerntet wurden aus einer zuvor beschriebenen XMeCP2-LUC-HR/xMeCP2 weibliche Maus, verewigt von retrovirale Transduktion von E6 und E7 Onkogene von HPV-16 virus7, geklont mit einschränkenden Verdünnung und getestet für Luciferase Aktivität und Expression von Wildtyp MeCP2 Protein (Abb. 1A und 1 b). Luciferase Aktivität war robust, wenn der Reporter auf Xa war und nicht nachweisbar wenn auf Xi; der native MeCP2 Ausdruck ausge...

Watch this Scientific Journal Video about Pooled shRNA Screen for Reactivation of MeCP2 on the Inactive X Chromosome at JoVE.com

Pooled shRNA Screen for Reactivation of MeCP2 on the Inactive X Chromosome

Gepoolte ShRNA Bildschirm für die Reaktivierung des MeCP2 auf dem inaktiven X-Chromosom

Wir berichten über eine kleine Hairpin RNA (ShRNA) und die nächste Generation Sequencing-basiertes Protokoll zur Identifizierung von Regulatoren der X-Chromosom Inaktivierung in einem murinen Zelllinie mit Firefly Luciferase und Hygromycin-Resistenz-Gene verschmolzen, das Methyl CpG verbindliches Protein 2) MeCP2) gen auf dem x-Chromosom inaktiv.

Forward genetic screens using reporter genes inserted into the heterochromatin have been extensively used to investigate mechanisms of epigenetic control ...

Begin this procedure with preparation of mouse tendon fibroblasts, as described in the text protocol. Harvest the cells from a 10-centimeter plate by first aspirating the media. Then add one milliliter of 0.05%trypsin EDTA and incubate for two to five minutes at 37-degrees Celsius.Following incubation, quench the trypsin with nine milliliters of DMEM-10, and collect the resuspended cells in a 15-milliliter conical tube. Dilute the cells with DMEM-10 to a final concentration of one cell per 100 microliters. Then transfer the cells to 96 well plates by pipetting 100 microliters of the suspension into each well.Incubate the cells at 37 degrees Celsius until the wells are confluent, which can take up to two to three weeks. Replace the media with fresh DMEM-10 every three to five days. When confluent, mobilize the cells with 20 microliters 0.05%trypsin EDTA per well, and split them into two duplicate sets of 96 well plates.Assay for luciferase activity in one set of plates. Use a homogenous Firefly luciferase assay that does not require media removal, following the protocol included with the luciferase assay kit. Use the assay results to select clones with no detectable luciferase activity from the remaining set of plates.Expand these clones first to a 24 well plate, and then to a six well plate. Perform the same for a clone with the highest luciferase activity. This will be used as a positive control for validation purposes.Following expansion in the six well plate, harvest an aliquot of each well for a Western blot. Mobilize the cells with 200 microliters of 0.05%trypsin EDTA. Incubate the cells for two to five minutes at 37 degrees Celsius.Quench the cells with two milliliters of DMEM-10, and transfer half of the cells to another six well plate. Wait until the cells attach to the bottom of the plate. Then wash the cells once with PBS before the lysing for the Western blot.Plate several negative clones at 0.2 million cells per well in a six well plate. Treat the cells once with 10 micromolar 5-azacytidine. Then incubate for 72 hours without changing the media before assaying for luciferase activity, as before.Next, choose one negative clone that gained luciferase activity with 5-azacytidine for the screen, and begin expanding it to multiple 10-centimeter plates. Freeze the remaining negative clones in liquid nitrogen as a backup. The positive clone can be maintained in the tissue culture or frozen until further use.In the morning, plate one million inactive X cells onto 10-centimeter tissue culture plates. In the afternoon, infect the plates by replacing the media with fresh DMEM-10 containing a predetermined amount of viral supernatant and five to 10 micrograms per milliliter of polybrene. After 18 to 24 hours, aspirate the media and add 10 milliliters of fresh DMEM-10 to each plate.Culture plates for another 48 hours. In the morning, mobilize the cells using one milliliter of 0.05%trypsin EDTA per plate, and quench the cells with 9 milliliters of DMEM-10 per plate. Run the suspension through a 100-micron mesh filter.Pull the filtered suspensions together, and seed two sets of 10-centimeter plates at one million cells per plate. In the afternoon, replace the media in one set of plates with DMEM-10 containing 15 micrograms per milliliter of Hygromycin B.In the other set, replace the media with fresh DMEM-10 only. After 48 hours, mobilize the cells from Hygromycin B untreated plates using one milliliter of 0.05%trypsin EDTA.Incubate for two to five minutes at 37 degrees Celsius. Next, quench the cells with 9 milliliters of DMEM-10. Pull the individual samples, and proceed immediately with extracting DNA.Continue culturing the Hygromycin B selection set for six more days, replenishing the selection media with fresh DMEM-10 containing Hygromycin B every other day. On day six, replace the selection media with fresh DMEM-10 only. Allow four days for recovery, and then harvest the post-selection sample DNA as before.Proceed to identify hairpins enriched in the post-selection samples, as described in the text protocol. To validate the hits, first seed eight million 293-FT cells per plate on 10-centimeter plates. The following day, replace the media with nine milliliters of antibiotic-free DMEM-10 per plate 30 minutes before transection.Next, add 0.5 milliliters of transfection mix one to each aliquot of transfection mix two, and gently mix by pipetting. Then incubate the mixture at room temperature for 20 minutes. Apply the mixture onto each plate in a drop-wise fashion, and swirl the plate gently to mix.The following day, replace the media with five milliliters of fresh DMEM-10.48 hours after initial transfection, collect the lentiviral supernatant, and run it through a 0.22-micron filter that has been prewet with DMEM-10 to maximize recovery. The next morning, plate 0.1 million inactive X cells per well onto six well plates. In the afternoon, infect the plates by replacing the media with two milliliters of fresh DMEM-10 containing lentiviral supernatant and five to 10 micrograms per milliliter of polybrene.Infect a control well with viral supernatant produced from an empty lentiviral vector. The following day, replace the media with two milliliters of DMEM-10 containing one milligram per milliliter of puromycin. Use selecting for four days.After four days, replace the media with two milliliters of fresh DMEM-10, and allow 48 to 72 hours for recovery. After mobilizing the cells with 150 microliters of 0.05%trypsin EDTA, incubate them for two to five minutes at 37 degrees Celsius. Quench the cells with 1.5 milliliters of DMEM-10 before transferring to conical tubes and centrifuging the cells at room temperature at 500 times G for 10 minutes.Remove the media and resuspended the cells in 100 microliters of lysis buffer provided in the luciferase assay kit. Incubate the suspension at room temperature for five minutes. After five minutes, transfer the suspension to a white 96 well plate.Perform the assay in the darkroom, following the protocol included in the kit. Use active X cells as a positive control and negative X cells infected with an empty lentiviral vector as a negative control. Immortalized mouse tendon fibroblast clones show either positive or negative Firefly luciferase activity, consistent with the placement of the reporter on the active or inactive X chromosome, respectively.MeCP2 expression, as determined by the Western blot, exhibits the reciprocal pattern. Note that Firefly luciferase activity can be induced in negative clones with administration of 5-azacitidine. If present on the active X chromosome, the Hygromycin resistance gene confers a survival advantage under Hygromycin selection, when compared to the cells with the gene on the inactive X chromosome.After watching this video, you should have a good understanding of how to design and perform a screen for regulators of X-chromosome inactivation using reporters selectively inserted on inactive X chromosome. My laboratory has previously carried out reported base screens for chromatin regulators in yeast, and our success with this approach inspired me to design this screen for regulators of X-chromosome inactivation in mammalian cells. Following this procedure, other methods, such as using small, interfering RNAs, CRISPR, small molecules can be performed to help answer additional questions regarding X-chromosome inactivation in mammalian cells.

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A Deep-sequencing-assisted, Spontaneous Suppressor Screen in the Fission Yeast Schizosaccharomyces pombe

A Deep-sequencing-assisted, Spontaneous Suppressor Screen in the Fission Yeast Schizosaccharomyces pombe

Ein Deep-Sequenzierung-gestützte, spontane Suppressor-Bildschirm in der Spalthefe Schizosaccharomyces pombe

A genetic screen for mutant alleles that suppress phenotypic defects caused by a mutation is a powerful approach to identify genes that belong to closely ...

A Non-random Mouse Model for Pharmacological Reactivation of Mecp2 on the Inactive X Chromosome

Ein nicht zufälliges Mausmodell zur pharmakologischen Reaktivierung von Mecp2 auf dem inaktiven X-Chromosom

X chromosome inactivation (XCI) is the random silencing of one X chromosome in females to achieve gene dosage balance between the sexes. As a result, all ...

Mass Spectrometry-Based Proteomics Analyses Using the OpenProt Database to Unveil Novel Proteins Translated from Non-Canonical Open Reading Frames

Massenspektrometrie-basierte Proteomics Analysen mithilfe der OpenProt-Datenbank zu enthüllen neue Proteine übersetzt aus dem nicht-kanonischen Open Reading Frames

Genome annotation is central to today's proteomic research as it draws the outlines of the proteomic landscape. Traditional models of open reading frame ...

Pooled CRISPR-Based Genetic Screens in Mammalian Cells

Gepoolte CRISPR-basierte genetische Screens in Säugetierzellen

Genome editing using the CRISPR-Cas system has vastly advanced the ability to precisely edit the genomes of various organisms. In the context of mammalian ...

A Screening Method for Identification of Heterochromatin-Promoting Drugs Using Drosophila

A Screening Method for Identification of Heterochromatin-Promoting Drugs Using Drosophila

Eine Screening-Methode zur Identifizierung von Heterochromatin-fördernden Medikamenten mit Drosophila

Drosophila is an excellent model organism that can be used to screen compounds that might be useful for cancer therapy. The method described here is a ...

Identification of Enhancer-Promoter Contacts in Embryoid Bodies by Quantitative Chromosome Conformation Capture (4C)

Identification of Enhancer-Promoter Contacts in Embryoid Bodies by Quantitative Chromosome Conformation Capture 4C

Identifizierung von Enhancer-Promoter-Kontakten in embryoiden Körpern durch quantitative Chromosomenkonformationserfassung (4C)

During mammalian development, cell fates are determined through the establishment of regulatory networks that define the specificity, timing, and spatial ...

A Suppressor Screen for the Characterization of Genetic Links Regulating Chronological Lifespan in Saccharomyces cerevisiae

A Suppressor Screen for the Characterization of Genetic Links Regulating Chronological Lifespan in Saccharomyces cerevisiae

Ein Suppressor-Bildschirm zur Charakterisierung genetischer Links, die die chronologische Lebensdauer in Saccharomyces cerevisiae regulieren

Aging is the time dependent deterioration of an organism&#8217;s normal biological processes that increases the probability of death. Many genetic factors ...

Application of DNA Fingerprinting using the D1S80 Locus in Lab Classes

Application of DNA Fingerprinting using the D1S80 Locus in Lab Classes

Anwendung von DNA Fingerprinting mit dem D1S80 Locus in Laborklassen

In biological sciences, DNA fingerprinting has been widely used for paternity testing, forensic applications and phylogenetic studies. Here, we describe a ...