Name: visualization and quantitative analysis of embryonic angiogenesis in xenopus tropicalis
Uploaded: 2017-05-25T14:00:00
Description: Watch this Scientific Journal Video about Visualization and Quantitative Analysis of Embryonic Angiogenesis in Xenopus tropicalis at JoVE.com

Denne studien ble inspirert av Levine et al. , Som beskrev denne eksperimentelle metoden og ga en omfattende beskrivelse av vaskulær utvikling i Xenopus laevis. Vi takker medlemmer av laboratoriet for deres innspill. Denne studien ble støttet av Yonsei Universitets fremtidsrettet forskningsinitiativ fra 2015 (2015-22- 0095) og Nasjonalt forskningsfonds bio- og medisinteknologiutviklingsprogram finansiert av departementet for vitenskap, IKT og fremtidig planlegging ( NRF-2013M3A9D5072551)

Alle eksperimenter fulgte protokoller godkjent av Yonsei University College of Medicine Institutional Animal Care og brukskomiteer. 1. Fremstilling av Xenopus tropicalis-embryoer MERK: Xenopus tropicalis- embryoer ble produsert som tidligere beskrevet 10 , med liten modifikasjon. Xenopus tropicalis- embryoer ble arrangert ifølge tabellene til Nieuwkoop og Faber 11 . <ol><li> Induksjon av eggløsning...

<ol>
	<li>Herbert, S. P., Stainier, D. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+control+of+endothelial+cell+behaviour+during+blood+vessel+morphogenesis.">Molecular control of endothelial cell behaviour during blood vessel morphogenesis.</a> Nat Rev Mol Cell Biol. 12 (9), 551-564 (2011).</li><li>Augustin, H. G., Koh, G. Y., Thurston, G., Alitalo, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Control+of+vascular+morphogenesis+and+homeostasis+through+the+angiopoietin-Tie+system.">Control of vascular morphogenesis and homeostasis through the angiopoietin-Tie system.</a> Nat Rev Mol Cell Biol. 10 (3), 165-177 (2009).</li><li>Lawson, N. D., Weinstein, B. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Arteries+and+veins:+making+a+difference+with+zebrafish.">Arteries and veins: making a difference with zebrafish.</a> Nat Rev Genet. 3 (9), 674-682 (2002).</li><li>Levine, A. J., Munoz-Sanjuan, I., Bell, E., North, A. J., Brivanlou, A. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluorescent+labeling+of+endothelial+cells+allows+in+vivo,+continuous+characterization+of+the+vascular+development+of+Xenopus+laevis.">Fluorescent labeling of endothelial cells allows in vivo, continuous characterization of the vascular development of Xenopus laevis.</a> Dev Biol. 254 (1), 50-67 (2003).</li><li>Yang, C., 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=Calmodulin+Mediates+Ca2+-Dependent+Inhibition+of+Tie2+Signaling+and+Acts+as+a+Developmental+Brake+During+Embryonic+Angiogenesis.">Calmodulin Mediates Ca2+-Dependent Inhibition of Tie2 Signaling and Acts as a Developmental Brake During Embryonic Angiogenesis.</a> Arterioscler Thromb Vasc Biol. 36 (7), 1406-1416 (2016).</li><li>Moody, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fates+of+the+blastomeres+of+the+32-cell-stage+Xenopus+embryo.">Fates of the blastomeres of the 32-cell-stage Xenopus embryo.</a> Dev Biol. 122 (2), 300-319 (1987).</li><li>Elliott, K. L., Houston, D. W., Fritzsch, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transplantation+of+Xenopus+laevis+tissues+to+determine+the+ability+of+motor+neurons+to+acquire+a+novel+target.">Transplantation of Xenopus laevis tissues to determine the ability of motor neurons to acquire a novel target.</a> PLoS One. 8 (2), 55541 (2013).</li><li>Grainger, 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=Xenopus+tropicalis+as+a+model+organism+for+genetics+and+genomics:+past,+present,+and+future.">Xenopus tropicalis as a model organism for genetics and genomics: past, present, and future.</a> Methods Mol Biol. 917, 3-15 (2012).</li><li>Weisgraber, K. H., Innerarity, T. L., Mahley, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+lysine+residues+of+plasma+lipoproteins+in+high+affinity+binding+to+cell+surface+receptors+on+human+fibroblasts.">Role of lysine residues of plasma lipoproteins in high affinity binding to cell surface receptors on human fibroblasts.</a> J Biol Chem. 253 (24), 9053-9062 (1978).</li><li>Showell, C., Conlon, F. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Egg+collection+and+in+vitro+fertilization+of+the+western+clawed+frog+Xenopus+tropicalis.">Egg collection and in vitro fertilization of the western clawed frog Xenopus tropicalis.</a> Cold Spring Harb Protoc. 2009 (9), 5293 (2009).</li><li>Nieuwkoop, P. D., Faber, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Normal Table of Xenopus laevis (Daudin). , (1956).</li><li>Longair, M. H., Baker, D. A., Armstrong, 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=Simple+Neurite+Tracer:+open+source+software+for+reconstruction,+visualization+and+analysis+of+neuronal+processes.">Simple Neurite Tracer: open source software for reconstruction, visualization and analysis of neuronal processes.</a> Bioinformatics. 27 (17), 2453-2454 (2011).</li><li>Marshak, S., Nikolakopoulou, A. M., Dirks, R., Martens, G. J., Cohen-Cory, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell-autonomous+TrkB+signaling+in+presynaptic+retinal+ganglion+cells+mediates+axon+arbor+growth+and+synapse+maturation+during+the+establishment+of+retinotectal+synaptic+connectivity.">Cell-autonomous TrkB signaling in presynaptic retinal ganglion cells mediates axon arbor growth and synapse maturation during the establishment of retinotectal synaptic connectivity.</a> J Neurosci. 27 (10), 2444-2456 (2007).</li><li>Cha, H. 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=Evolutionarily+repurposed+networks+reveal+the+well-known+antifungal+drug+thiabendazole+to+be+a+novel+vascular+disrupting+agent.">Evolutionarily repurposed networks reveal the well-known antifungal drug thiabendazole to be a novel vascular disrupting agent.</a> PLoS Biol. 10 (8), 1001379 (2012).</li><li>Ny, 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+transgenic+Xenopus+laevis+reporter+model+to+study+lymphangiogenesis.">A transgenic Xenopus laevis reporter model to study lymphangiogenesis.</a> Biol Open. 2 (9), 882-890 (2013).</li><li>Bussmann, 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=Arteries+provide+essential+guidance+cues+for+lymphatic+endothelial+cells+in+the+zebrafish+trunk.">Arteries provide essential guidance cues for lymphatic endothelial cells in the zebrafish trunk.</a> Development. 137 (16), 2653-2657 (2010).</li><li>Li, X. M., Hu, Z., Jorgenson, M. L., Slayton, W. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+levels+of+acetylated+low-density+lipoprotein+uptake+and+low+tyrosine+kinase+with+immunoglobulin+and+epidermal+growth+factor+homology+domains-2+(Tie2)+promoter+activity+distinguish+sinusoids+from+other+vessel+types+in+murine+bone+marrow.">High levels of acetylated low-density lipoprotein uptake and low tyrosine kinase with immunoglobulin and epidermal growth factor homology domains-2 (Tie2) promoter activity distinguish sinusoids from other vessel types in murine bone marrow.</a> Circulation. 120 (19), 1910-1918 (2009).</li></ol>

Protokollen presentert her ble først utviklet av Ali H. Brivanlou og kollegaer for å undersøke utviklingshendelser under vaskulær formasjon i Xenopus laevis 4 , men som vist i dette manuskriptet, kan den brukes på andre små dyr. Fargestoffinjeksjon i hjertet er enkelt å utføre, og hele det vaskulære nettverket kan avbildes under et fluorescensdisseksjonsmikroskop, samt et konfokalt mikroskop. Hvis fargestoffet injiseres i hjertet under fartøyets utvikling, kan dynamikken i fart...

Vaskulogenese, dannelsen av nye blodkar fra nyfødte endotelceller og angiogenese, dannelsen av nye fartøy fra eksisterende fartøy, er to forskjellige prosesser som danner embryonisk vaskulatur 1 . Eventuell dysregulering i disse prosessene resulterer i forskjellige hjertesykdommer og strukturelle abnormiteter i kar. Videre er tumorvekst assosiert med ukontrollert kar-vekst. Som sådan er molekylære mekanismer som ligger bak vasculogenese og angiogenese gjenstand for intens undersøkelse 2 . Xenopus og sebrafisk er attraktive hvirveldyrsmodeller for vaskulogenese og angiogenesestudier, av flere grunner. For det første er deres embryoer små; Derfor er det relativt enkelt å bilde hele karet. For det andre er embryonisk utvikling rask; Det tar bare et par dager for hele vaskulaturen å utvikle, i løpet av hvilken tid utvikler vascul<html> Ature kan bli avbildet. Tredje genetisk og farmakologisk inngrep før og under fartøydannelse er lett å utføre, for eksempel gjennom mikroinjeksjon av antisense morfolino nukleotider (MOs) i det utviklende embryo eller gjennom badapplikasjonen av legemidler 3 , 4 , 5 . Den unike fordelen med Xenopus over sebrafisk er at embryologiske manipulasjoner kan utføres fordi Xenopus følger stereotypiske holoblastiske spaltninger, og det embryonske skjebnen er godt definert 6 . For eksempel er det mulig å generere et embryo hvor bare en lateral side er genetisk manipulert ved å injisere en antisense MO til en celle i tocelletrinnet. Det er også mulig å transplantere hjertet primordium fra ett embryo til et annet for å avgjøre om genet utøver sin funksjon ved hjelp av en celle-inneboende eller -ekstrinsisk mekanismeAss = &quot;xref&quot;&gt; 7. Selv om disse teknikkene for det meste har blitt utviklet i Xenopus laevis , som er allotetraploid og derfor ikke er ideell for genetiske studier, kan de brukes direkte til Xenopus tropicalis , en nært beslektet diploid art 8 . En måte å visualisere vaskulaturen på i et levende Xenopus- embryo er å injisere et fluorescerende fargestoff for å merke blodårene. Acetylert lavdensitetslipoprotein (AcLDL) merket med et fluorescerende molekyl som DiI er en meget nyttig probe. I motsetning til ikke-acetylert LDL, binder AcLDL ikke til LDL-reseptoren 9, men endocytteres av makrofager og endotelceller. Injeksjonen av DiI-AcLDL inn i hjertet av et levende dyr resulterer i den spesifikke fluorescensmerking av endotelceller, og hele vaskulaturen kan avbildes ved fluorescensmikroskopi i levende eller faste embryoer 4 . Her presiserer viEnt detaljerte protokoller for visualisering og kvantifisering av blodkar ved hjelp av DiI-AcLDL i Xenopus tropicalis ( Figur 1 ). Vi gir viktige praktiske poeng, med eksempler på vellykkede og mislykkede eksperimenter. I tillegg gir vi en enkel metode for kvantitativ analyse av vaskulær kompleksitet, noe som kan være nyttig for å vurdere effektene av genetiske og miljømessige faktorer ved utformingen av det vaskulære nettverket.

<table border="0" cellpadding="0" cellspacing="0" width="539">
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	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">35mm Petri dish</td>
			<td style="width:113px;">SPL</td>
			<td style="width:93px;">10035</td>
			<td style="width:180px;">Sylgard mold frame</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">60mm Petri dish</td>
			<td style="width:113px;">SPL</td>
			<td style="width:93px;">10060</td>
			<td>Embryo raising tray</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">Borosilicate Glass</td>
			<td style="width:113px;">Sutter instrument</td>
			<td style="width:93px;">B100-50-10</td>
			<td>Needle for injection</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">BSA</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">A3059-10G</td>
			<td>Coating reagent</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">CaCl2</td>
			<td style="width:113px;">D.S.P.GR Reagent</td>
			<td style="width:93px;"></td>
			<td>0.1X MBS component</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Coverslip</td>
			<td style="width:113px;">Superior</td>
			<td style="width:93px;">HSU-0111520</td>
			<td>For confocal imaging</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">DiI-AcLDL</td>
			<td style="width:113px;">Thermo Fisher Scientific</td>
			<td style="width:93px;">L3484</td>
			<td>Vessel staining solution</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">FBS</td>
			<td style="width:113px;">Hyclone</td>
			<td style="width:93px;">SH.30919.02</td>
			<td>For storage of testis</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">Fiber Optical Illuminator</td>
			<td style="width:113px;">World Precision Instruments</td>
			<td style="width:93px;">Z-LITE-Z</td>
			<td>Light</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Ficoll</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">F4375</td>
			<td>Injection buffer</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">Flaming/Brown Micropipette Puller</td>
			<td style="width:113px;">Sutter instrument</td>
			<td style="width:93px;">P-97</td>
			<td>Injection needle puller</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">Forcep</td>
			<td style="width:113px;">Fine Science Tool</td>
			<td style="width:93px;">11255-20</td>
			<td style="width:180px;">For embryo hatching and 
			needle tip cutting</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Glass Bottom dish</td>
			<td style="width:113px;">SPL</td>
			<td style="width:93px;">100350</td>
			<td>For confocal imaging</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">hCG</td>
			<td style="width:113px;">MNS Korea</td>
			<td style="width:93px;"></td>
			<td>For priming of frogs</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">HEPES</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">H3375</td>
			<td>Buffering agent</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Incubator</td>
			<td style="width:113px;">Lab. Companion</td>
			<td style="width:93px;">ILP-02</td>
			<td>For raising embryos</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">KCl</td>
			<td style="width:113px;">DAEJUNG</td>
			<td style="width:93px;">6566-4400</td>
			<td>MBS component</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">L15 medium</td>
			<td style="width:113px;">Gibco</td>
			<td style="width:93px;">11415-114</td>
			<td>For storage of testis</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">L-cysteine</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">168149-100G</td>
			<td>De-jellying reagent</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">MgSO4</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">M7506</td>
			<td>MBS component</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Microtube</td>
			<td style="width:113px;">Axygen</td>
			<td style="width:93px;">MCT-175-C-S</td>
			<td>For storage of testis</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">MS222</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">E10521</td>
			<td>Anesthetic powder</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">NaCl</td>
			<td style="width:113px;">DAEJUNG</td>
			<td style="width:93px;">7647-14-5</td>
			<td>MBS component</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">NaOH</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">S-0899</td>
			<td>pH adjusting reagent</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Paraformaldehyde</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">P6148</td>
			<td>Fixatives</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">PBS</td>
			<td style="width:113px;">BIOSESANG</td>
			<td style="width:93px;">P2007</td>
			<td>Buffer for imaging</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">pH paper</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">P4536-100EA</td>
			<td>For confirming pH</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">PICO-LITER INJECTOR</td>
			<td style="width:113px;">Waner instruments</td>
			<td style="width:93px;">PLI-100A</td>
			<td>For injection</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Pin</td>
			<td style="width:113px;">Pinservice</td>
			<td style="width:93px;">26002-10</td>
			<td>For incision</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Pinholder</td>
			<td style="width:113px;">Scitech Korea</td>
			<td style="width:93px;">26016-12</td>
			<td>For incision</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">Precision Stereo Zoom Binocular Microscope</td>
			<td style="width:113px;">World Precision Instruments</td>
			<td style="width:93px;">PZMIII</td>
			<td>For visual screening</td>
		</tr>
		<tr height="60">
			<td height="60" style="height:60px;width:153px;">Standard Manual Control Micromanipulator&#160;</td>
			<td style="width:113px;">Waner instruments</td>
			<td style="width:93px;">W4 64-0056</td>
			<td>For microinjection</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">SYLGARD 184 Kit</td>
			<td style="width:113px;">Dow Corning</td>
			<td style="width:93px;"></td>
			<td>For DiI injection</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">Transfer pipette</td>
			<td style="width:113px;">Korea Ace Scientific Co.</td>
			<td style="width:93px;">YM.B78-400</td>
			<td>For eggs and 
			embryo collection</td>
		</tr>
	</tbody>
</table>

visualization and quantitative analysis of embryonic angiogenesis in xenopus tropicalis

Blodkar leverer oksygen og næringsstoffer gjennom hele kroppen, og dannelsen av det vaskulære nettverket er under tett utviklingskontroll. Effektiv in vivo visualisering av blodkar og pålitelig kvantifisering av deres kompleksitet er nøkkelen til å forstå biologien og sykdommen i det vaskulære nettverket. Her gir vi en detaljert metode for å visualisere blodkar med et kommersielt tilgjengelig fluorescerende fargestoff, humant plasma acetylert lavdensitets lipoprotein DiI-kompleks (DiI-AcLDL), og for å kvantifisere deres kompleksitet i Xenopus tropicalis . Blodkar kan merkes med en enkel injeksjon av DiI-AcLDL inn i et embryo som slår på hjertet, og blodkar i hele embryoet kan avbildes i levende eller faste embryoer. Kombinert med genforstyrrelser ved målrettet mikroinjeksjon av nukleinsyrer og / eller badapplikasjon av farmakologiske reagenser, kan roller av et gen eller en signalvei på vaskulær utvikling være invektetØkte innen en uke uten å gripe til sofistikerte genetisk utviklede dyr. På grunn av det veldefinerte venesystemet av Xenopus og dets stereotypiske angiogenese kan spiring av eksisterende fartøy, kompleksitet av fartøy, kvantifiseres effektivt etter perturbasjonseksperimenter. Denne relativt enkle protokollen skal fungere som et lett tilgjengelig verktøy i ulike felt av kardiovaskulær forskning.

Tidslinje for eksperimenter (figur 1 og 2) Kort etter befruktning kan målrettet mikroinjeksjon utføres for å modulere genuttrykk. For eksempel kan en antisense MO som spesifikt binder til initieringskodonet til det endogene Tie2-mRNA injiseres, hemme oversettelsen av Tie2-målmRNA ved sterisk hindring. En MO kan bli konjugert til fluorescein for enkel visuell screening av vellykket injiserte embryoer. Alternativt kan et sporin...

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Visualization and Quantitative Analysis of Embryonic Angiogenesis in Xenopus tropicalis

Denne protokollen demonstrerer en fluorescensbasert metode for å visualisere vaskulaturen og å kvantifisere kompleksiteten i Xenopus tropicalis . Blodkar kan bli avbildet minutter etter injeksjon av et fluorescerende fargestoff inn i et embryos slårhjerte etter genetisk og / eller farmakologisk manipulasjon for å studere kardiovaskulær utvikling in vivo .

Visualisering og kvantitativ analyse av embryonisk angiogenese i<em&gt; Xenopus tropicalis</em

Blood vessels supply oxygen and nutrients throughout the body, and the formation of the vascular network is under tight developmental control. The ...

The overall goal of this procedure is to visualize the vasculature of Xenopus tropicalis tadpoles. This method can help answer key questions in the field of cardiovascular biology such as how angiogenesis is regulated. The main advantage of this technique is that blood vessels in an intact well type embryo can be visualized by a simple fluorescent dye injection.Begin by using a micro loader to fill a tapered glass micro pipette with approximately five microliters of clear diI acetylated LDL solution taking care that no precipitated particles are loaded. Under a dissecting microscope use a fine pair of number 55 forceps to clip the tip of the pipette to adjust the volume of the uploaded complex and set the pressure controlled injection system to eject approximately five nano liters of solution per injection. Then submerge the pipette tip in 0.04%MS-222 in 0.1X modified Barth's saline or MBS in a custom made Sylgard mold.Next transfer Xenopus tropicalis embryo to the Sylgard mold and confirm complete sedation with a lack of response to dorsal fin stimulation. Under the dissecting microscope load the embryo ventral side up into the V shaped indentation of the mold in a slightly oblique position. Tightly fit two 0.1 millimeter minutian pins to a pin holder and use one pin to puncture the skin over the heart which should be visibly pulsing.Insert the pin through the hole in the space between the heart and the skin without puncturing the heart and position the inserted tip within the region where the incision will be made. Then rub the second pin against the inserted pin to make a linear incision and use both pins together to gently widen the incision, exposing the heart. To inject the DiI acetylated LDL solution, insert the glass pipette tip into the heart and inject 50 to 60 nano liters of the DiI acetylated LDL in approximately 10 ejection pulses.When all of the dye solution has been delivered confirm that the heart is still beating and transfer the embryo into a new Petri dish containing 0.1X MBS. After five to 10 minutes the tadpole should recover from anesthesia and begin to move. After an appropriate number of embryos have been injected, visually screen the correctly labeled anesthetized embryos under a fluorescence microscope discarding any animals that have other organs labeled.Embryos that have been insufficiently labeled can be injected again. Then capture images of the correctly labeled embryos. For a more thorough imaging of the blood vessels, fix re anesthetized embryos in 4%paraformaldehyde for one hour at room temperature protected from light for visualization by confocal microscopy.If a sufficient amount of diI acetylated LDL is injected into the heart, the posterior cardinal vein, or PCV, should be immediately visible under a fluorescence microscope. The intersomitic veins, or ISV's, emerge dorsally from the PCV in an anterior to posterior wave beginning at stage 36 and ending around stage 40 to 41 becoming lightly branched around stage 43. The PCV and ISV's grow in a stereotypical angiogenic pattern that is under tight developmental control.Interestingly, the knockdown of TIE-2 signaling by antisense morphalinos decreases the length and the complexity of the ISV's whereas expression of the constitutively active form of TIE-2 induces excessive ISV branching. A Vein Complexity Index can be calculated to assess the complexity of the ISV's and rendered paths can be generated to visualize the overall architecture of the embryonic Xenopus tropicalis vasculature. The original protocol was described for using Xenopus laevis by Levin and Colics and we adapted it for Xenopus tropicalis.Once mastered, this technique can be completed in one hour if it is performed properly. Before this procedure, genetic and pharmacological manipulations can be performed to answer additional questions such as which genes and signaling pathways regulate vascular development. Using this procedure the labeled vasculature can be imaged in an intact animal in real time providing a powerful tool for investigating the dynamics of vascular development.After watching this video you should have a good understanding of how to inject diI acetylated LDL into the heart of a Xenopus tropicalis tadpole to visualize it's vasculature.

Research

JoVE Journal

Developmental Biology

Visualization and Quantitative Analysis of Embryonic Angiogenesis in Xenopus tropicalis

Manipulation and In Vitro Maturation of Xenopus laevis Oocytes, Followed by Intracytoplasmic Sperm Injection, to Study Embryonic Development

Manipulation and In Vitro Maturation of Xenopus laevis Oocytes, Followed by Intracytoplasmic Sperm Injection, to Study Embryonic Development

Manipulasjon og<em&gt; In Vitro</em&gt; Modning av<em&gt; Xenopus laevis</em&gt; Oocytter, etterfulgt av Intracytoplasmatisk Sperm Injection, for å studere embryoutvikling

Amphibian eggs have been widely used to study embryonic development. Early embryonic development is driven by maternally stored factors accumulated during ...

Analysis of Cardiomyocyte Development using Immunofluorescence in Embryonic Mouse Heart

Analyse av cardiomyocyte Development hjelp Immunfluorescens i Embryonic Mouse Hjerte

During heart development, the generation of myocardial-specific structural and functional units including sarcomeres, contractile myofibrils, intercalated ...

Visualization of Chondrocyte Intercalation and Directional Proliferation via Zebrabow Clonal Cell Analysis in the Embryonic Meckel&#8217;s Cartilage

Visualisering av chondrocyttransplantasjon innskyting og Directional spredning via Zebrabow Klonal Cell Analysis i Embryonic Meckels Brusk

Development of the vertebrate craniofacial structures requires precise coordination of cell migration, proliferation, adhesion and differentiation. ...

Stem cell-like Xenopus Embryonic Explants to Study Early Neural Developmental Features In Vitro and In Vivo

Stem cell-like Xenopus Embryonic Explants to Study Early Neural Developmental Features In Vitro and In Vivo

Stamcellelignende<em&gt; Xenopus</em&gt; Embryonale eksplantater å studere Tidlig Neural utviklingstrekk<em&gt; In Vitro</em&gt; Og<em&gt; I Vivo</em

Understanding the genetic programs underlying neural development is an important goal of developmental and stem cell biology. In the amphibian blastula, ...

Transcriptome Profiling of In-Vivo Produced Bovine Pre-implantation Embryos Using Two-color Microarray Platform

Transcriptome Profiling of In-Vivo Produced Bovine Pre-implantation Embryos Using Two-color Microarray Platform

Transkriptom profilering av<em&gt; In-Vivo</em&gt; Produserte Bovine Pre-implantasjon Embryoet ved hjelp av to-farge microarray plattform

Early embryonic loss is a large contributor to infertility in cattle. Moreover, bovine becomes an interesting model to study human preimplantation embryo ...

Technique to Target Microinjection to the Developing Xenopus Kidney

Technique to Target Microinjection to the Developing Xenopus Kidney

Teknikken til Target Mikroinjeksjon til utviklings<em&gt; Xenopus</em&gt; Nyre

The embryonic kidney of Xenopus&#160;laevis (frog), the pronephros, consists of a single nephron, and can be used as a model for kidney disease. Xenopus ...

Analysis of Coronary Vessels in Cleared Embryonic Hearts

Analyse av koronarkar i Slettet embryonale Hearts

Whole mount visualization of the embryonic coronary plexus from which the capillary and arterial networks will form is rendered problematic using standard ...

Light-mediated Reversible Modulation of the Mitogen-activated Protein Kinase Pathway during Cell Differentiation and Xenopus Embryonic Development

Light-mediated Reversible Modulation of the Mitogen-activated Protein Kinase Pathway during Cell Differentiation and Xenopus Embryonic Development

Lysmediert reversibel modulering av den mitogenaktiverte proteinkinaseveien under celledifferensiering og<em&gt; Xenopus</em&gt; Embryonutvikling

Kinase activity is crucial for a plethora of cellular functions, including cell proliferation, differentiation, migration, and apoptosis. During early ...

Quantitative Whole-mount Immunofluorescence Analysis of Cardiac Progenitor Populations in Mouse Embryos

Kvantitativ hele-mount Immunofluorescence analyse av Cardiac stamfar populasjoner i Mouse embryoer

The use of ever-advancing imaging techniques has contributed broadly to our increased understanding of embryonic development. Pre-implantation development ...