Name: analysis of line-1 retrotransposition at the single nucleus level
Uploaded: 2016-04-23T14:00:00
Description: Watch this Scientific Journal Video about Analysis of LINE-1 Retrotransposition at the Single Nucleus Level at JoVE.com

This work was supported in part by grants from the National Institute of Environmental Health Sciences (ES014443 and ES017274) and AstraZeneca to KSR.

NOTE: Alle trinn bør utføres ved romtemperatur med mindre annet er angitt. Vennligst referer til Reagenser seksjon for detaljer om hvordan å forberede enkelt reagenser. 1. merking L1 prober MERK: prober kan merkes ved kjemisk eller PCR merking. <ol><li> kjemisk merking <ol><li> Gjør 0,7 til 1% agarosegel i Tris-acetat-EDTA (TAE) -buffer, varme i en mikrobølgeovn inntil smeltet, at gelen avkjøles, og deretter legge til etidiumbrom...

<ol>
	<li>Mathias, S. L., Scott, A. F., Kazazian, H. H., Boeke, J. D., Gabriel, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reverse+transcriptase+encoded+by+a+human+transposable+element.">Reverse transcriptase encoded by a human transposable element.</a> Science. 254, 1808-1810 (1991).</li><li>Feng, Q., Moran, J. V., Kazazian, H. H., Boeke, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+L1+retrotransposon+encodes+a+conserved+endonuclease+required+for+retrotransposition.">Human L1 retrotransposon encodes a conserved endonuclease required for retrotransposition.</a> Cell. 87, 905-916 (1996).</li><li>Clements, A. P., Singer, M. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+human+LINE-1+reverse+transcriptase:effect+of+deletions+outside+the+common+reverse+transcriptase+domain.">The human LINE-1 reverse transcriptase:effect of deletions outside the common reverse transcriptase domain.</a> Nucl Acids Res. 26, 3528-3535 (1998).</li><li>Martin, S. L., Branciforte, D., Keller, D., Bain, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Trimeric+structure+for+an+essential+protein+in+L1+retrotransposition.">Trimeric structure for an essential protein in L1 retrotransposition.</a> Proc. Natl. Acad. Sci. U.S.A. 100, 13815-13820 (2003).</li><li>Khazina, E., 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=Trimeric+structure+and+flexibility+of+the+L1ORF1+protein+in+human+L1+retrotransposition.">Trimeric structure and flexibility of the L1ORF1 protein in human L1 retrotransposition.</a> Nat Struct Mol Biol. 18, 1006-1014 (2011).</li><li>Martin, S. L., Li, J., Weisz, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deletion+analysis+defines+distinct+functional+domains+for+protein-protein+and+nucleic+acid+interactions+in+the+ORF1+protein+of+mouse+LINE-1.">Deletion analysis defines distinct functional domains for protein-protein and nucleic acid interactions in the ORF1 protein of mouse LINE-1.</a> J Mol Biol. 304, 11-20 (2000).</li><li>Martin, S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ribonucleoprotein+particles+with+LINE-1+RNA+in+mouse+embryonal+carcinoma+cells.">Ribonucleoprotein particles with LINE-1 RNA in mouse embryonal carcinoma cells.</a> Mol Cell Biol. 11 (9), 4804-4807 (1991).</li><li>Hohjoh, H., Singer, M. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cytoplasmic+ribonucleoprotein+complexes+containing+human+LINE-1+protein+and+RNA.">Cytoplasmic ribonucleoprotein complexes containing human LINE-1 protein and RNA.</a> EMBO J. 15, 630-639 (1996).</li><li>Cost, G. J., Feng, Q., Jacquier, A., Boeke, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+L1+element+target-primed+reverse+transcription+in+vitro.">Human L1 element target-primed reverse transcription in vitro.</a> EMBO J. 21, 5899-5910 (2002).</li><li>Szak, S. T., 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=Molecular+archeology+of+L1+insertions+in+the+human+genome.">Molecular archeology of L1 insertions in the human genome.</a> Genome Biol. 3, (2002).</li><li>Sen, S. K., Huang, C. T., Han, K., Batzer, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Endonuclease-independent+insertion+provides+an+alternative+pathway+for+L1+retrotransposition+in+the+human+genome.">Endonuclease-independent insertion provides an alternative pathway for L1 retrotransposition in the human genome.</a> Nucl Acids Res. 35, 3741-3751 (2007).</li><li>Bojang, P., Roberts, R. A., Anderton, M. J., Ramos, K. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reprogramming+of+the+HepG2+genome+by+long+interspersed+nuclear+element-1.">Reprogramming of the HepG2 genome by long interspersed nuclear element-1.</a> Mol Oncol. 7, 812-825 (2013).</li><li>Boeke, J. D., Garfinkel, D. J., Styles, C. A., Fink, G. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ty+elements+transpose+through+an+RNA+intermediate.">Ty elements transpose through an RNA intermediate.</a> Cell. 40, 491-500 (1985).</li><li>Heidmann, T., Heidmann, O., Nicolas, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+indicator+gene+to+demonstrate+intracellular+transposition+of+defective+retroviruses.">An indicator gene to demonstrate intracellular transposition of defective retroviruses.</a> PNAS. 85, 2219-2223 (1988).</li><li>Moran, J. V., 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=High+frequency+retrotransposition+in+cultured+mammalian+cells.">High frequency retrotransposition in cultured mammalian cells.</a> Cell. 87, 917-927 (1996).</li><li>Bojang, P., Anderton, M. J., Roberts, R. A., Ramos, K. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=De+novo+LINE-1+retrotransposition+in+HepG2+cells+preferentially+targets+gene+poor+regions+of+chromosome+13.">De novo LINE-1 retrotransposition in HepG2 cells preferentially targets gene poor regions of chromosome 13.</a> Genomics. 104, 96-104 (2014).</li><li>Rozen, 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=Abundant+gene+conversion+between+arms+of+palindromes+in+human+and+ape+Y+chromosomes.">Abundant gene conversion between arms of palindromes in human and ape Y chromosomes.</a> Nature. 423, 873-876 (2003).</li><li>Graves, J. A., Koina, E., Sankovic, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=How+the+gene+content+of+human+sex+chromosomes+evolved.">How the gene content of human sex chromosomes evolved.</a> Curr Op Gen Develop. 16, 219-224 (2006).</li><li>Leem, Y. E., 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=Retrotransposon+Tf1+is+targeted+to+Pol+II+promoters+by+transcription+activators.">Retrotransposon Tf1 is targeted to Pol II promoters by transcription activators.</a> Mol Cell. 30, 98-107 (2008).</li><li>Guo, Y., Levin, H. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-throughput+sequencing+of+retrotransposon+integration+provides+a+saturated+profile+of+target+activity+in+Schizosaccharomyces+pombe.">High-throughput sequencing of retrotransposon integration provides a saturated profile of target activity in Schizosaccharomyces pombe.</a> Genome Res. 20, 239-248 (2010).</li><li>Dai, J., Xie, W., Brady, T. L., Gao, J., Voytas, D. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phosphorylation+regulates+integration+of+the+yeast+Ty5+retrotransposon+into+heterochromatin.">Phosphorylation regulates integration of the yeast Ty5 retrotransposon into heterochromatin.</a> Mol Cell. 27, 289-299 (2007).</li><li>McClintock, C. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+origin+and+behavior+of+mutable+loci+in+maize.">The origin and behavior of mutable loci in maize.</a> Proc. Natl. Acad. Sci. U.S.A. 36, 344-355 (1950).</li><li>Fernandez, L., Torregrosa, L., Segura, V., Bouquet, A., Martinez-Zapater, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transposon-induced+gene+activation+as+a+mechanism+generating+cluster+shape+somatic+variation+in+grapevine.">Transposon-induced gene activation as a mechanism generating cluster shape somatic variation in grapevine.</a> Plant J Cell Mol Biol. 61, 545-557 (2010).</li><li>Garcia-Perez, J. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epigenetic+silencing+of+engineered+L1+retrotransposition+events+in+human+embryonic+carcinoma+cells.">Epigenetic silencing of engineered L1 retrotransposition events in human embryonic carcinoma cells.</a> Nature. 466 (7307), 769-773 (2010).</li><li>Rodic, N., 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=Retrotransposon+insertions+in+the+clonal+evolution+of+pancreatic+ductual+adenocarcinoma.">Retrotransposon insertions in the clonal evolution of pancreatic ductual adenocarcinoma.</a> Nat Med. 21 (9), (2015).</li></ol>

Metoder som hele genomsekvensering, invers PCR og sørlige blotting har blitt ansatt for å studere L1 retrotransposition. Selv om disse metodene er svært verdifulle i å finne hvor L1 innsett skje innen genomer, en confounding utfordring for dem alle er behovet for in-silico programing å montere sekvenser. FISH metoden beskrevet her, er utformet for å komplettere disse metoder, særlig i tilfelle av studier som krever analyse av ektopisk L1 retrotransposition i dyrkede celler. Fre...

Menneskelig Long ispedd Nuclear Element-en (Linje 1 eller L1) er en autonom mobil element som forplanter seg i genomet gjennom en &quot;kopier og lim&quot; retrotransposition mekanisme. En typisk human L1 er ~ 6 kb langt og består av en 5&#39;UTR (ikke-translatert område) som fungerer som en promoter, to åpne leserammer (ORF): L1 -ORF1 og L1 -ORF2, og en 3&#39;UTR med en polyA . tail L1 -ORF1 protein har tre forskjellige domener: en spiral spiral domene, RNA anerkjennelse Motif og C-terminal domene, mens L1 -ORF2 protein har endonuklease, reverstranskriptasehemmere og cystein rike domener 1,2,3,4,5. L1 -ORF1 viser nukleinsyre anstand aktiviteter, mens L1 -ORF2 gir enzymatiske aktiviteter, med både proteiner som kreves for retrotransposition 1,2,6. En syklus av L1 retrotransposition starter med transkripsjon fra 5&#39;UTR av L1 </em&gt; bicistronisk mRNA ved RNA polymerase II, translokasjon inn i cytoplasma, og oversettelse. I cytoplasma, L1 -ORF1 utstillinger enten cis -binding hvor det pakker sin egen RNA eller trans -binding hvor det pakker andre RNA (dvs. sinus / SVAs / pseudogener) for å danne en ribonucleoprotein partikkel (RNP) med L1 -ORF2p 7, 8. RNPs translocate inn i kjernen der endonuklease-aktiviteten til L1 -ORF2p hakk genomisk DNA (gDNA) for å eksponere en OH - gruppe 9, som er i sin tur anvendes ved revers transkriptase for å prime revers og syntetisere RNA til DNA fra 3&#39;-enden. Under revers syntese, er den andre DNA bretter 7-20 bp fra den opprinnelige nick området for å skape forskjøvet pauser som er fylt til å danne signatur L1 innsetting sekvenser (f.eks TTTTAA) kalt target språk duplikasjoner (TSD) 9,10. Denne prosessen er kjent som target prime revers transkripsjon (TPRT) og fører til insertipå av full eller avkortede kopier av L1 / andre DNA med TSDs i begge ender av den innførte sekvens. L1 retrotransposition har også vist seg å være mediert gjennom TPRT-lignende ikke-homologe ende-sammenføyning i visse celletyper 11. L1 retrotransposition vektor anvendt i våre studier er ikke-episomale og består av merket L1 -ORF1 &amp; 2p drevet av kombinerte CMV-promotere L1-5&#39;UTR (figur 1) 12. Tidligere versjoner av denne konstruksjonen har blitt beskrevet i studier med gjær og humane cellekulturer 13,14,15. To distinkte CMV promotorer som ligger ved 5 &#39;og 3&#39; ender av vektoren, sammen med 3&#39;-enden som er lagt inn i motsatt retning for å drive ekspresjon av neomycin etter spleising og integrasjon. Den retrotransposition indikatoren kassetten ved 3&#39;-enden inneholder et neomycin-genet innsatt antisense til L1 -ORFs og gjøres inaktive ved separasjon i to halvdeler ved en globi intron med skjøtes donor (SD) og skjøtes akseptor (SA) nettsteder (figur 1). Ved integrering inn i et kromosom er L1 transkribert fra en felles promoter for å fremstille et mRNA som består av en bicistronisk mRNA og inaktive neomycin mRNA. Under RNA prosessering, blir globin intron spleiset ut av neomycin-genet for å gjenopprette en fullstendig funksjonell neomycin-genet. Det hybride mRNA er pakket inn i en RNP i cis- og translokert til kjernen, hvor det er integrert i genomet som enten full lengde eller avkortet innføringer ved hjelp av TPRT. Her beskriver vi en metode som bruker fluorescens in situ hybridisering (FISH) med prober spesifikt rettet mot skjøtes neomycin-genet (sneo) for å spore L1 -retrotransposiition mønstre og innsetting priser på enkelt kjernen nivå. Effektiviteten og spesifisitet for påvisning ble bekreftet ved hjelp retrotransposition kompetent og inkompetente konstruerer og sonder til Detect sneo eller neomycin og globin intron veikryss 16. Denne metodikken står for noen av svakhetene i cellekultur basert retrotransposition analyser, for eksempel flere innsettinger, koloni motstand og gunstig klon ekspansjon.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Labeling Probes</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Go Tag DNA polymerase</td>
			<td>Promega</td>
			<td>M3178</td>
			<td></td>
		</tr>
		<tr>
			<td>GO Tag 10X colorless buffer</td>
			<td>Promega</td>
			<td>M3178</td>
			<td></td>
		</tr>
		<tr>
			<td>Individual dNTP</td>
			<td>Sigma</td>
			<td>DNTP10</td>
			<td>Adjust the concentration of dATP, dGTP, dCTP to 2mM and dTTP to 1.5mM&#160; in nuclease free water.</td>
		</tr>
		<tr>
			<td>&#160;dUTP-16-Biotin (0.5mM)</td>
			<td>Roche</td>
			<td>11093070910</td>
			<td></td>
		</tr>
		<tr>
			<td>dUTP-FITC (0.5mM)</td>
			<td>Thermo Scientific</td>
			<td>R0101</td>
			<td></td>
		</tr>
		<tr>
			<td>dUTP-CY3 (0.5mM)</td>
			<td>Sigma</td>
			<td>GEPA53022</td>
			<td></td>
		</tr>
		<tr>
			<td>MIRUS FISH Labeling Kit</td>
			<td>MIRUS</td>
			<td>MIR3625</td>
			<td></td>
		</tr>
		<tr>
			<td>MIRUS FISH Labeling Kit</td>
			<td>MIRUS</td>
			<td>MIR3225</td>
			<td></td>
		</tr>
		<tr>
			<td>NucleoSpin PCR Clean-Up kit&#160;</td>
			<td>Qiagen</td>
			<td>1410/0030</td>
			<td>Any PCR clean reagent can be used in place of NucleoSpin PCR Clean Up Kit</td>
		</tr>
		<tr>
			<td>PCR Machine</td>
			<td></td>
			<td></td>
			<td>Any Thermocycler machine can be used to amplify the label product.</td>
		</tr>
		<tr>
			<td>Agarose</td>
			<td>Sigma</td>
			<td>A9539</td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Preparing chromosome Spreads.</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>&#160;&#160;&#160;&#160; Colcemid&#160;</td>
			<td>Life Technologies&#160;</td>
			<td>15212-012</td>
			<td>Add Colcemid directly to growth media&#160; to a final concentration of 0.4 &#181;g/mL</td>
		</tr>
		<tr>
			<td>1M KCl</td>
			<td>Sigma</td>
			<td>P9541</td>
			<td>Dilute 1M KCl solution to 75 mM solution to make Hypotonic Solution</td>
		</tr>
		<tr>
			<td>Carnoy Fixative Solution</td>
			<td></td>
			<td></td>
			<td>Mix 3 volumes of methanol and 1 volume of acetic acid to make Carnoy Fixative Solution. Make Fresh everytime.</td>
		</tr>
		<tr>
			<td>Methanol</td>
			<td>Sigma</td>
			<td>322415</td>
			<td></td>
		</tr>
		<tr>
			<td>Acetic acid</td>
			<td>Sigma</td>
			<td>320099</td>
			<td></td>
		</tr>
		<tr>
			<td>Hoechst-33342</td>
			<td>Thermo Scientific</td>
			<td>62249</td>
			<td>Dissolve Hoechst-33342 in PBS to final concentration of 1 mg/mL.</td>
		</tr>
		<tr>
			<td>Diamond Point Marker</td>
			<td>Thermo Scientific</td>
			<td>750</td>
			<td></td>
		</tr>
		<tr>
			<td>Frosted Slides</td>
			<td>Thermo Scientific</td>
			<td>2951-001</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypsin-EDTA (0.25%)</td>
			<td>Life Technologies&#160;</td>
			<td>R001100</td>
			<td>To detech cells, incubate cell in Trypsin for 5 mins and inactive with equal volume of complete media</td>
		</tr>
		<tr>
			<td>Cover slides&#160;</td>
			<td>VWR</td>
			<td>48366067</td>
			<td></td>
		</tr>
		<tr>
			<td>Coplin Jars</td>
			<td>Thermo Scientific</td>
			<td>107</td>
			<td></td>
		</tr>
		<tr>
			<td>&#160;Heat Block</td>
			<td></td>
			<td></td>
			<td>Any heat block can be used for this purpose, though blocks fitted for heating slides are recommended.</td>
		</tr>
		<tr>
			<td>&#160;Beaker (600ml)</td>
			<td>Sigma</td>
			<td>CLS1003600</td>
			<td>Fill the beaker with water, heat to boil, use the hot steam to burst chromosomes.</td>
		</tr>
		<tr>
			<td>Nikon Microscope</td>
			<td>Nikon</td>
			<td>125690</td>
			<td>Any microscope can be used to look at spread quality.</td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Reagents and Materials for FISH</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Trisodium citrate</td>
			<td>Sigma</td>
			<td>S1804</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium Chroride</td>
			<td>Sigma</td>
			<td>S3014</td>
			<td></td>
		</tr>
		<tr>
			<td>Formamide</td>
			<td>Sigma</td>
			<td>F9037</td>
			<td></td>
		</tr>
		<tr>
			<td>Tween-20</td>
			<td>Sigma</td>
			<td>F1379</td>
			<td></td>
		</tr>
		<tr>
			<td>Detran Sulfate</td>
			<td>Sigma</td>
			<td>D8906</td>
			<td></td>
		</tr>
		<tr>
			<td>SDS</td>
			<td>Sigma</td>
			<td>L3771</td>
			<td></td>
		</tr>
		<tr>
			<td>Salmon Sperm DNA</td>
			<td>Life Technologies&#160;</td>
			<td>15632-011</td>
			<td></td>
		</tr>
		<tr>
			<td>Bovine Serum Albumin (BSA)</td>
			<td>Sigma</td>
			<td>A8531</td>
			<td></td>
		</tr>
		<tr>
			<td>HCl (N)</td>
			<td>Sigma</td>
			<td>38283</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethyl Alcohol</td>
			<td>Sigma</td>
			<td>459844</td>
			<td></td>
		</tr>
		<tr>
			<td>Methanol</td>
			<td>Sigma</td>
			<td>322415</td>
			<td></td>
		</tr>
		<tr>
			<td>DPBS</td>
			<td>Life Technologies&#160;</td>
			<td>14190-250</td>
			<td></td>
		</tr>
		<tr>
			<td>NaOH</td>
			<td>Sigma</td>
			<td>S8045</td>
			<td></td>
		</tr>
		<tr>
			<td>Rnase A</td>
			<td>Sigma</td>
			<td>R4642</td>
			<td></td>
		</tr>
		<tr>
			<td>Pepsin</td>
			<td>Sigma</td>
			<td>P6887</td>
			<td></td>
		</tr>
		<tr>
			<td>Paraformaldehyde (PFA)</td>
			<td>Sigma</td>
			<td>P6148</td>
			<td></td>
		</tr>
		<tr>
			<td>Hoechst-33342</td>
			<td>Thermo Scientific</td>
			<td>62249</td>
			<td>Dissolve Hoechst-33342 in PBS to final concentration of 1 mg/mL.</td>
		</tr>
		<tr>
			<td>Rubber Cement/Cytobond Sealant&#160;</td>
			<td></td>
			<td>2020-00-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Seven Coplin Jars</td>
			<td>Thermo Scientific</td>
			<td>107</td>
			<td></td>
		</tr>
		<tr>
			<td>&#160; Dark Humidified chamber</td>
			<td>Sigma</td>
			<td>CLS2551</td>
			<td></td>
		</tr>
		<tr>
			<td>Cover slides&#160;</td>
			<td>VWR</td>
			<td>48366067</td>
			<td></td>
		</tr>
		<tr>
			<td>Dry Digital Heat Block</td>
			<td>VWR</td>
			<td>13259</td>
			<td></td>
		</tr>
		<tr>
			<td>&#160;Fluorescence Microscope</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>20X Saline-Sodium Citrate (20X SSC)</td>
			<td></td>
			<td></td>
			<td>Combine 175 g of NaCl, and 88.2 g of trisodium citrate with 800 mL of molecular grade H2O. Stir while adjusting to pH 7. Once the all salts dissolve, adjust the volume to 1 L and filter through 0.22 &#181;m Filter paper. Store at 4 &#176;C.</td>
		</tr>
		<tr>
			<td>&#160;1mg/mL of Rnase A</td>
			<td></td>
			<td></td>
			<td>Dilute 20X SSC buffer to 2X SSC buffer. Dissolve RNase A in 2X SSC buffer to a final concentration of 1 mg/mL. Make fresh solution every time.</td>
		</tr>
		<tr>
			<td>1% Pepsin</td>
			<td></td>
			<td></td>
			<td>Dissolve&#160; pepsin (W/V) in 10 mM HCl to a final concentration of 1 % solution. Make fresh every time.</td>
		</tr>
		<tr>
			<td>4% Paraformaldehyde (4% PFA)</td>
			<td></td>
			<td></td>
			<td>Weigh 4.0 g of PFA in fume hood, add 50 mL of 1xPBS, heat to 60 &#176;C while stirring and adjust the pH with drops of NaOH until all PFA dissolves and the solution becomes clear. Adjust the volume to 100 mL, filter through 0.22 &#181;m Filter paper and store 5 mL aliquots at -20 &#176;C. Thaw aliquot of PFA at 37 &#176;C for 10-15 min for subsequent uses.&#160; Adjust filter size depending on amount of paraformaldehyde.</td>
		</tr>
		<tr>
			<td>Wash Buffer</td>
			<td></td>
			<td></td>
			<td>Combine 100 mL of Formamide (20%) with 2.5 mL of 20X SSC, adjust to pH 7 with 1.0 M HCl and bring the volume to 500 mL with molecular grade H2O.</td>
		</tr>
		<tr>
			<td>Hybridization Buffer</td>
			<td></td>
			<td></td>
			<td>Combine 50% formamide, 10% dextran sulfate, 0.1% SDS, and 300 ng/mL Salmon Sperm DNA in 2X SSC buffer.&#160; Amount of Formamide determine how focused chromatids are, titrate the amount&#160;</td>
		</tr>
		<tr>
			<td>Detection Buffer</td>
			<td></td>
			<td></td>
			<td>Dilute 20X SSC buffer to 4X and add 0.2% Tween-20 to make detection buffer.</td>
		</tr>
		<tr>
			<td>Blocking Buffer</td>
			<td></td>
			<td></td>
			<td>Combine 5% bovine serum albumin (BSA) with 0.2% Tween-20 in 4X SSC buffer.</td>
		</tr>
		<tr>
			<td>Dehydrating Solution</td>
			<td></td>
			<td></td>
			<td>Make 70%, 80%, and 95% ethanol solutions.</td>
		</tr>
	</tbody>
</table>

analysis of line-1 retrotransposition at the single nucleus level

Long interspersed nuclear element-1 (Line-1 or L1) accounts for approximately 17% of the DNA present in the human genome. While the majority of L1s are inactive due to 5' truncations, ~80-100 of these elements remain retrotransposition competent and propagate to different locations throughout the genome via RNA intermediates. While older L1s are believed to target AT rich regions of the genome, the chromosomal targets of newer, more active L1s remain poorly defined. Here we describe fluorescence in situ hybridization (FISH) methodology that can be used to track patterns of L1 insertion and rates of ectopic L1 incorporation at the single nucleus level. In these experiments, fluorescein isothiocyanate/cyanine-3 (FITC/CY3) labeled neomycin probes were employed to track L1 retrotransposition in vitro in HepG2 cells stably expressing ectopic L1. This methodology prevents errors in the estimation of rates of retrotransposition posed by toxicity and account for the occurrence of multiple insertions into a single nucleus.

Et skjematisk diagram av L1 retrotransposition vektoren blir presentert i figur 1. Vektoren inneholder et neomycin-genet i antisense-orientering for å L1 ORF&#39;er som er avbrutt av et globin intron i sense-orientering og klemt til SD og SA områder. Når stabilt integrert inn i et kromosom er L1 mRNA transkribert fra det kombinerte CMV og L1-5&#39;UTR promoteren (figur 1). Under RNA prosessering, blir globin intron spleiset ...

Watch this Scientific Journal Video about Analysis of LINE-1 Retrotransposition at the Single Nucleus Level at JoVE.com

Analysis of LINE-1 Retrotransposition at the Single Nucleus Level

Analyse av LINE-en Retrotransposition på enkelt Nucleus nivå

Her benytter vi FISH metode for å spore LINE-en retrotransposition på enkelt kjerner nivå i kromosom sprer av HepG2 cellelinjer stabilt uttrykker syntetisk LINE-en.

Long interspersed nuclear element-1 (Line-1 or L1) accounts for approximately 17% of the DNA present in the human genome. While the majority of L1s are ...

Research

JoVE Journal

Biology

Method for Measurement of Viral Fusion Kinetics at the Single Particle Level

Membrane fusion is an essential step during entry of enveloped viruses into cells. Conventional fusion assays typically report on a large number of fusion ...

Direct Analysis of Single Cells by Mass Spectrometry at Atmospheric Pressure

Analysis of biochemicals in single cells is important for understanding cell metabolism, cell cycle, adaptation, disease states, etc. Even the same cell ...

Studying Proteolysis of Cyclin B at the Single Cell Level in Whole Cell Populations

Studerer proteolyse av Cyclin B på Single Cell nivå i hele cellepopulasjoner

Equal distribution of chromosomes between the two daughter cells during cell division is a prerequisite for guaranteeing genetic stability 1. Inaccuracies ...

Efficient Agroinfiltration of Plants for High-level Transient Expression of Recombinant Proteins

Effektiv Agroinfiltration of Plants for High-level Forbigående Expression of rekombinante proteiner

Mammalian cell culture is the major platform for commercial production of human vaccines and therapeutic proteins. However, it cannot meet the increasing ...

Analysis of Global RNA Synthesis at the Single Cell Level following Hypoxia

Analyse av global RNA syntese på celle-nivå etter Hypoksi

Hypoxia or lowering of the oxygen availability is involved in many physiological and pathological processes. At the molecular level, cells initiate a ...

CUBIC Protocol Visualizes Protein Expression at Single Cell Resolution in Whole Mount Skin Preparations

CUBIC Protocol Visualiserer Protein Expression på enkelt celle oppløsning i Hele Mount hud preparater

The skin is essential for our survival. The outer epidermal layer consists of the interfollicular epidermis, which is a stratified squamous epithelium ...

Analysis of Beta-cell Function Using Single-cell Resolution Calcium Imaging in Zebrafish Islets

Analyse av Beta-celle-funksjonen bruker encellede oppløsning kalsium Imaging i sebrafisk holmer

Pancreatic beta-cells respond to increasing blood glucose concentrations by secreting the hormone insulin. The dysfunction of beta-cells leads to ...

Visualizing the Interaction Between the Qdot-labeled Protein and Site-specifically Modified &#955; DNA at the Single Molecule Level

Visualizing the Interaction Between the Qdot-labeled Protein and Site-specifically Modified ÃƒÆ’Ã…Â½Ãƒâ€šÃ‚Â» DNA at the Single Molecule Level

Visualisere samspillet mellom Qdot-merket Protein og Site-specifically endret λ DNA på ett molekyl nivå

The fluorescence microscopy&#160;has made great contributions in dissecting the mechanisms of complex biological processes at the single molecule level. ...

Probing mRNA Kinetics in Space and Time in Escherichia coli using Two-Color Single-Molecule Fluorescence In Situ Hybridization

Probing mRNA Kinetics in Space and Time in Escherichia coli using Two-Color Single-Molecule Fluorescence In Situ Hybridization

Sondering av mRNA Kinetikk i rom og tid i Escherichia coli ved hjelp av to-farge enkeltmolekyl fluorescens i Situ hybridisering

Single-molecule fluorescence in situ hybridization (smFISH) allows for counting the absolute number of mRNAs in individual cells. Here, we describe an ...