نشكر راديك Sindelka لمساعدته، وكاس Bresilla لمساعدة مع تربية الضفادع وإعداد الجنين. وقد تم تمويل هذا العمل من قبل المعاهد الوطنية للصحة عن طريق R01DE021109 منحة لورا HLS Jacox بتمويل من زمالة الدراسات العليا هيرشيل سميث في جامعة هارفارد، ومنحة الزمالة F30-01 F30DE022989 الفردية من خلال NIDCR.

<ol>
	<li>Gorlin, R. J., Cohen, M., Levin, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Syndromes of the head and neck. , (1990).</li><li>Trainor, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Craniofacial+birth+defects:+The+role+of+neural+crest+cells+in+the+etiology+and+pathogenesis+of+Treacher+Collins+syndrome+and+the+potential+for+prevention.">Craniofacial birth defects: The role of neural crest cells in the etiology and pathogenesis of Treacher Collins syndrome and the potential for prevention.</a> Am. J. Med. Gen. A. 152, 2984-2994 (2010).</li><li>Dickinson, A. J., Sive, 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=Development+of+the+primary+mouth+in+Xenopus+laevis.">Development of the primary mouth in Xenopus laevis.</a> Dev. Bio. 295, 700-713 (2006).</li><li>Dickinson, A. J., Sive, 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=Positioning+the+extreme+anterior+in+Xenopus:+cement+gland,+primary+mouth+and+anterior+pituitary.">Positioning the extreme anterior in Xenopus: cement gland, primary mouth and anterior pituitary.</a> Sem. Cell Dev. Bio. 18, 525-533 (2007).</li><li>Dickinson, A. J., Sive, 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=The+Wnt+antagonists+Frzb-1+and+Crescent+locally+regulate+basement+membrane+dissolution+in+the+developing+primary+mouth.">The Wnt antagonists Frzb-1 and Crescent locally regulate basement membrane dissolution in the developing primary mouth.</a> Dev. 136, 1071-1081 (2009).</li><li>Gilbert, S. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Developmental Biology. , (2010).</li><li>Borchers, A., Epperlein, H. H., Wedlich, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+assay+system+to+study+migratory+behavior+of+cranial+neural+crest+cells+in+Xenopus.">An assay system to study migratory behavior of cranial neural crest cells in Xenopus.</a> Dev. Genes Evol. 210, 217-222 (2000).</li><li>Grunz, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Homoiogenetic+neural+inducing+activity+of+the+presumptive+neural+plate+of+Xenopus+laevis.">Homoiogenetic neural inducing activity of the presumptive neural plate of Xenopus laevis.</a> Dev. Growth Differ. 32, 583-589 (1990).</li><li>Servetnick, M., 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=Changes+in+neural+and+lens+competence+in+Xenopus+ectoderm:+evidence+for+an+autonomous+developmental+timer.">Changes in neural and lens competence in Xenopus ectoderm: evidence for an autonomous developmental timer.</a> Dev. Bio. 112, 177-188 (1991).</li><li>Servetnick, M., 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=Homeogenetic+neural+induction+in+Xenopus.">Homeogenetic neural induction in Xenopus.</a> Dev. Bio. 147, 73-82 (1991).</li><li>Couly, G., Coltey, P., Le Douarin, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+triple+origin+of+skull+in+higher+vertebrates:+a+study+in+quail-chick+chimeras.">The triple origin of skull in higher vertebrates: a study in quail-chick chimeras.</a> Dev. 117, 409-429 (1993).</li><li>Couly, G. F., Le Douarin, N. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mapping+of+the+early+neural+primordium+in+quail-chick+chimeras+:+I.">Mapping of the early neural primordium in quail-chick chimeras : I.</a> Developmental relationships between placodes, facial ectoderm. 110, 422-439 (1985).</li><li>Couly, G. F., Le Douarin, N. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mapping+of+the+early+neural+primordium+in+quail-chick+chimeras+II.+The+prosencephalic+neural+plate+and+neural+folds:+Implications+for+the+genesis+of+cephalic+human+congenital+abnormalities.">Mapping of the early neural primordium in quail-chick chimeras II. The prosencephalic neural plate and neural folds: Implications for the genesis of cephalic human congenital abnormalities.</a> Dev. Bio. 120, 198-214 (1987).</li><li>Lievre, A. 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Bio. 365, 229-240 (2012).</li><li>Trainor, P., Tam, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cranial+paraxial+mesoderm+and+neural+crest+of+the+mouse+embryo-+codistribution+in+the+craniofacial+mesenchyme+but+distinct+segregation+in+the+branchial+arches.">Cranial paraxial mesoderm and neural crest of the mouse embryo- codistribution in the craniofacial mesenchyme but distinct segregation in the branchial arches.</a> Dev. 121, 2569-2582 (1995).</li><li>Sive, H. L., Grainger, R. M., Harland, 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=.">.</a> Early Development of Xenopus laevis. , (2000).</li><li>Tandon, P., Showell, C., Christine, K., Conlon, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morpholino+injection+in+Xenopus.">Morpholino injection in Xenopus.</a> Methods Mol. Biol. 843, 29-46 (2012).</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). , (1994).</li></ol>

والكتاب ليس لديهم ما يكشف.

خطوات حاسمة والقيود: إن EAD وجه إجراء عملية زرع حان الوقت والعمل المكثف. ذلك يتطلب ممارسة واليدين ثابتة، والبراعة إلى الكمال. يعتمد بروتوكول زرع وجه على قدرة الباحث لإزالة الأنسجة بكفاءة والزرع. إذا كان واحد يأخذ وقتا طويلا لإدراج زرع في وجه المضيف، ووجه المضيف بدء...

لفهم الآليات الكامنة وراء العيوب القحفي الولادة 1-2، والأنسجة الهامة والمساهمات إشارة أثناء تطوير القحفي يجب تحديدها. في الضفدع القيطم المورق، جزء من الوجه، بما في ذلك الفم وشكل الخياشيم من &quot;المتطرفة الأمامي المجال&quot; (EAD)، حيث الأديم الظاهر الأديم الباطن ويتم جنبا إلى جنب مباشرة 3-4. يعمل EAD أيضا كمركز إشارات للتأثير على الأنسجة المحيطة بها، بما في ذلك قمة العصبية في الجمجمة، الذي يشكل الفكين والوجه المناطق الأخرى 5. لتحديد الجينات التي تساهم في وظيفة هيئة البيئة، وقد تم تطوير تقنية &quot;زرع وجه&quot;، حيث يتم زرع أنسجة من متبرع إلى الجنين المضيف، بعد إزالة منطقة المضيف المقابلة. بعد زرع، مما أدى تنمية الوجه وتقييمها. وبالتالي، يتم تحليل آثار فقدان وظيفة (LOF) أو مكسب من وظيفة (GOF) لجين معين في هيئة البيئة محليا، حيث بقية حوتتألف هيئة البيئة والجسم من النوع البري الأنسجة. زرع متبادلة لا يمكن أن يؤديها، حيث يتم زرع نوع البرية الأنسجة في الأجنة مع LOF العالمية أو صندوق القناص في جينات معينة. وقد تم زرع يكثر استخدامها في القيطم والدراسات فرخ 6. على سبيل المثال، تناول زرع القيطم الحث متماثل التوالد العصبية، عدسة والكفاءة العصبية، والعصبية الهجرة قمة 7-10. السمان-فرخ تطعيم خيالية وقد حللت تطوير لوحة الأمامية العصبية، التلال العصبية الأمامي، قمة العصبية، وعظام الجمجمة 11-14. هذا هو الأسلوب زرع أول لدراسة التنمية القحفي في القيطم. وقد أثبتت هذه التقنية دورا رواية لمثبطات WNT Frzb1 والهلال في تنظيم تشكيل الغشاء القاعدي في الفم الظني 5. القيطم المورق هو نموذج مثالي لدراسة التطور القحفي كما أجنة كبيرة، وتطوير خارجيا، والثانية الوجه مرئيا بسهولة، مما يسمح المجهرية والتصوير التنمية. تظهر الآليات الكامنة وراء تطوير الوجه حفظها، مشيرا إلى أن النتائج قدمت في الضفدع توفير نظرة ثاقبة التنمية البشرية 4،15-16.

<table border="0" cellpadding="0" cellspacing="0" width="559">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:195px;">Pasteur pipette</td>
			<td rowspan="3" style="width:101px;">VWR</td>
			<td rowspan="3" style="width:136px;">14672-400</td>
			<td style="width:128px;">Lime Glass&#160;</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:195px;">Size 5 3/4&#8217;&#8217;</td>
			<td style="width:128px;">Cotton Plugged</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:195px;"></td>
			<td style="width:128px;">Disposable</td>
		</tr>
		<tr height="20">
			<td height="41" rowspan="2" style="height:41px;width:195px;">Graduated Transfer Pipette</td>
			<td rowspan="2" style="width:101px;">VWR</td>
			<td rowspan="2" style="width:136px;">16001-180</td>
			<td style="width:128px;">Disposable&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:128px;">Polyethylene</td>
		</tr>
		<tr height="80">
			<td height="100" rowspan="2" style="height:100px;width:195px;">#5/45 forceps</td>
			<td rowspan="2" style="width:101px;">Fine Science Tools by Dupont medical</td>
			<td rowspan="2" style="width:136px;">11251-35</td>
			<td rowspan="2" style="width:128px;">Angled 45 degrees</td>
		</tr>
		<tr height="20">
		</tr>
		<tr height="40">
			<td height="81" rowspan="3" style="height:81px;width:195px;">Standard Pattern Forceps</td>
			<td rowspan="3" style="width:101px;">Fine Science Tools</td>
			<td rowspan="3" style="width:136px;">11000-20</td>
			<td style="width:128px;">Straight; serrated tip</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:128px;">Stainless Steel;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:128px;">20cm long</td>
		</tr>
		<tr height="60">
			<td height="81" rowspan="2" style="height:81px;width:195px;">Capillary Tubing (for needles)</td>
			<td rowspan="2" style="width:101px;">FHC</td>
			<td rowspan="2" style="width:136px;">30-30-1</td>
			<td style="width:128px;">Borosil 1.0mm OD x 0.5mm ID/Fiber</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:128px;">100mm each</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:195px;">Cover slip&#160;</td>
			<td rowspan="4" style="width:101px;">VWR</td>
			<td style="width:136px;">48393 252&#160;</td>
			<td style="width:128px;">24x60mm&#160;</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:195px;">micro cover glass</td>
			<td style="width:136px;">or&#160;</td>
			<td style="width:128px;">or&#160;</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:195px;">(for glass bridges)</td>
			<td style="width:136px;">48393 230</td>
			<td style="width:128px;">24x40mm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:195px;">No.1.5</td>
			<td style="width:136px;"></td>
			<td style="width:128px;"></td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:195px;">Ficoll 400</td>
			<td style="width:101px;">Sigma-Aldrich</td>
			<td style="width:136px;">F9378</td>
			<td style="width:128px;"></td>
		</tr>
		<tr height="60">
			<td height="60" style="height:60px;width:195px;">Needle Puller&#160;</td>
			<td style="width:101px;">Sutter Instrument Co</td>
			<td rowspan="3" style="width:136px;">Needle Puller: discontinued Filament: FB300B</td>
			<td rowspan="3" style="width:128px;">The most similar, currently available&#160; needle puller is the P-97. For filaments, use Sutter 3.00mm square box filaments, 3.0mm wide.</td>
		</tr>
		<tr height="80">
			<td height="80" style="height:80px;width:195px;">Model P-80</td>
			<td style="width:101px;">Flaming / Brown micropipette puller</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:195px;">(discontinued)</td>
			<td style="width:101px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:195px;">Stereomicroscope</td>
			<td rowspan="2" style="width:101px;">Zeiss</td>
			<td rowspan="2" style="width:136px;"></td>
			<td rowspan="2" style="width:128px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:195px;">Zeiss Stemi 1000</td>
		</tr>
		<tr height="61">
			<td height="61" style="height:61px;width:195px;">Stereomicroscope Lighting by Fostec</td>
			<td style="width:101px;">Fostec</td>
			<td style="width:136px;"></td>
			<td style="width:128px;">Use a light box with 2 fiberoptic arms.&#160;&#160;</td>
		</tr>
		<tr height="60">
			<td height="81" rowspan="2" style="height:81px;width:195px;">Nickel Plated Pin Holder</td>
			<td rowspan="2" style="width:101px;">Fine Science Tools</td>
			<td rowspan="2" style="width:136px;">26018-17</td>
			<td style="width:128px;">Jaw Opening Diameter: 0 to 1mm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:128px;">Length: 17cm</td>
		</tr>
		<tr height="60">
			<td height="101" rowspan="3" style="height:101px;width:195px;">Moria Nickel Plated Pin Holder</td>
			<td rowspan="3" style="width:101px;">Fine Science Tools</td>
			<td rowspan="3" style="width:136px;">26016-12</td>
			<td style="width:128px;">Jaw opening Diameter: 0 to 1mm</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:128px;">Length: 12cm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:128px;"></td>
		</tr>
		<tr height="40">
			<td height="60" rowspan="2" style="height:60px;width:195px;">Tungsten Needles</td>
			<td rowspan="2" style="width:101px;">Fine Science Tools</td>
			<td rowspan="2" style="width:136px;">10130-05</td>
			<td rowspan="2" style="width:128px;">0.125mm Rod diameter</td>
		</tr>
		<tr height="20">
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:195px;">Van Aken Plastalina</td>
			<td rowspan="2" style="width:101px;">Blick&#160;</td>
			<td rowspan="2" style="width:136px;">#33268-2981</td>
			<td rowspan="2" style="width:128px;"></td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:195px;">Modeling Clay- white, red or yellow</td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:195px;">mMessage mMashine SP6 or T7 Kit</td>
			<td style="width:101px;">Ambion</td>
			<td style="width:136px;">AM1340</td>
			<td style="width:128px;"></td>
		</tr>
	</tbody>
</table>

facial transplants in xenopus laevis embryos

تحدث العيوب الخلقية القحفي في 1 من كل 700 ولادة حية، ولكن نادرا ما يعرف المسببات بسبب الفهم المحدود للتنمية القحفي. لتحديد حيث مسارات الإشارات والأنسجة التصرف خلال الزخرفة من الوجه النامية، وقد تم تطوير تقنية &quot;زرع وجه&quot; في الأجنة الضفدع القيطم المورق. تتم إزالة المنطقة من أنسجة الوجه الظني (في &quot;المتطرفة الأمامي المجال&quot; (EAD)) من جنين المانحة في مرحلة tailbud، وزرعها إلى الجنين المضيف من نفس المرحلة، والتي تمت إزالة المنطقة يعادلها. وهذا يمكن أن تستخدم لتوليد وجه خيالية حيث الأنسجة المضيفة أو المانحة له الخسارة أو الربح من وظيفة في الجينات، و / أو يتضمن تسمية النسب. بعد الشفاء، ويتم رصد نتائج التنمية، ويشير إلى أدوار مسار الإشارات داخل الجهة المانحة أو الأنسجة المحيطة المضيف. القيطم يمثل نموذجا قيما للتنمية وجهه، ومنطقة الوجه كبيرة وبسهولة وccessible لالمجهرية. يمكن أن يعاير العديد من الأجنة، على مدى فترة زمنية قصيرة منذ حدوث التنمية بسرعة. النتائج في الضفدع ذات الصلة بالتنمية البشرية، منذ ظهور عمليات الحفظ القحفي بين القيطم والثدييات.

ينبغي إدراج الأنسجة المزروعة بالكامل في رأس المضيف بعد زرع كما هو مبين في الشكل 3A، ولها جسر زجاجي يوضع بشكل مناسب على وجه الجنين، كما هو مبين في الشكل 2BC. يجب أن يكون الحجم الأنسجة المانحة المزروعة بشكل صحيح لافتتاح المضيف، لزرع لتكون ناجحة. يجب الأن...

Watch this Scientific Journal Video about Facial Transplants in Xenopus laevis Embryos at JoVE.com

Facial Transplants in Xenopus laevis Embryos

تقنية لزرع &quot;المتطرفة الأمامي المجال&quot; بين أنسجة الوجه القيطم المورق وقد تم تطوير الأجنة. يمكن نقل الأنسجة من احد خلفية التعبير الجيني إلى أخرى، والسماح للدراسة المتطلبات المحلية للتنمية والقحفي للانزعاج التفاعلات بين مناطق الوجه.

زرع الوجه في<em&gt; القيطم المورق</em&gt; الأجنة

Craniofacial birth defects occur in 1 out of every 700 live births, but etiology is rarely known due to limited understanding of craniofacial development. ...

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Biology

Facial Transplants in Xenopus laevis Embryos

10.1K Views.  Harvard University.  تقنية لزرع "المتطرفة الأمامي المجال" بين أنسجة الوجه القيطم المورق وقد تم تطوير الأجنة. يمكن نقل الأنسجة من احد خلفية التعبير الجيني إلى أخرى، والسماح للدراسة المتطلبات المحلية للتنمية والقحفي للانزعاج التفاعلات بين مناطق الوج?...

Video: Facial Transplants in Xenopus laevis Embryos

Dissection of Organizer and Animal Pole Explants from Xenopus laevis Embryos and Assembly of a Cell Adhesion Assay

This video demonstrates the technique used for preparation of organizer and animal pole explants from Xenopus laevis embryos, including the use of the eyebrow knife - a specialized dissection tool made of one's eyebrow. The protocol for assembling an adhesion assay is also given, which probes for the presence of key adhesion molecules present on the surface organizer or animal pole cells that are critical for proper development.

تشريح المنظم وExplants القطب الحيواني من أجنة القيطم المورق وجمعية خلية الفحص الالتصاق

Plastic Embedding and Sectioning of Xenopus laevis Embryos

Plastic sections maintain true tissue morphology in thin sections of tissue that can be immunostained with fluorescent secondary antibodies, making this method more useful than paraffin-embedded or frozen sections for many types of tissue. The method for staining, plastic embedding, and sectioning is demonstrated in this video.

البلاستيك وتضمينها Sectioning الجنين المورق القيطم

Obtaining Eggs from Xenopus laevis Females

The eggs of Xenopus laevis intact, lysed, and/or fractionated are useful for a wide variety of experiments. This protocol shows how to induce egg laying, collect and dejelly the eggs, and sort the eggs to remove any damaged eggs.

The eggs of Xenopus laevis intact, lysed, and/or fractionated are useful for a wide variety of experiments. This protocol shows how to induce egg laying, collect and dejelly the eggs, and sort the eggs to remove any damaged eggs.

الحصول على البيض من الإناث المورق القيطم

The eggs of Xenopus laevis intact, lysed, and/or fractionated are useful for a wide variety of experiments. This protocol shows how to induce egg laying, ...

Preparation and Fractionation of Xenopus laevis Egg Extracts

Crude and fractionated Xenopus egg extracts can be used to provide ingredients for reconstituting cellular processes for morphological and biochemical analysis. Egg lysis and differential centrifugation are used to prepare the crude extract which in turn in used to prepare fractionated extracts and light membrane preparations.

Crude and fractionated Xenopus egg extracts can be used to provide ingredients for reconstituting cellular processes for morphological and biochemical analysis. Egg lysis and differential centrifugation are used to prepare the crude extract which in turn in used to prepare fractionated extracts and light membrane preparations.

إعداد والتقطير من البيض مقتطفات القيطم المورق

Crude and fractionated Xenopus egg extracts can be used to provide ingredients for reconstituting cellular processes for morphological and biochemical ...

Microinjection of Xenopus Laevis Oocytes

Microinjection of Xenopus laevis oocytes followed by thin-sectioning electron microscopy (EM) is an excellent system for studying nucleocytoplasmic transport. Because of its large nucleus and high density of nuclear pore complexes (NPCs), nuclear transport can be easily visualized in the Xenopus oocyte. Much insight into the mechanisms of nuclear import and export has been gained through use of this system (reviewed by Pant&eacute;, 2006). In addition, we have used microinjection of Xenopus oocytes to dissect the nuclear import pathways of several viruses that replicate in the host nucleus. 
Here we demonstrate the cytoplasmic microinjection of Xenopus oocytes with a nuclear import substrate. We also show preparation of the injected oocytes for visualization by thin-sectioning EM, including dissection, dehydration, and embedding of the oocytes into an epoxy embedding resin. Finally, we provide representative results for oocytes that have been microinjected with the capsid of the baculovirus Autographa californica nucleopolyhedrovirus (AcMNPV) or the parvovirus Minute Virus of Mice (MVM), and discuss potential applications of the technique.

Here we demonstrate cytoplasmic microinjection of Xenopus laevis oocytes with a nuclear import substrate, as well as preparation of the injected oocytes for visualization by thin-sectioning electron microscopy.

Microinjection من البويضات المورق القيطم

Microinjection of Xenopus laevis oocytes followed by thin-sectioning electron microscopy (EM) is an excellent system for studying nucleocytoplasmic ...

Tissue Determination Using the Animal Cap Transplant (ACT) Assay in Xenopus laevis

Many proteins play a dual role in embryonic development. Those that regulate cell fate determination in a specific tissue can also affect the development of a larger region of the embryo. This makes defining its role in a particular tissue difficult to analyze. For example, noggin overexpression in Xenopus laevis embryos causes the expansion of the entire anterior region, including the eye1,2. From this result, it is not known if Noggin plays a direct role in eye determination or that by causing an expansion of neural tissue, Noggin indirectly affects eye formation. Having this complex phenotype makes studying its eye-specific role in cell fate determination difficult to analyze. We have developed an assay that overcomes this problem. Taking advantage of the pluripotent nature of the Xenopus laevis animal cap 3, we have developed an assay to test the ability of gene product(s), like noggin or the eye field transcription factors (EFTFs), to transform caps into particular tissue or cell types by transplanting this tissue onto the side of the embryo 4. While we have found either Noggin protein treatment or a collection of transcription factors can determine retinal cell fate in animal caps, this procedure could be used to identify gene product(s) involved in specifying other tissues as well.

Tissue Determination Using the Animal Cap Transplant ACT Assay in Xenopus laevis

Animal caps overexpressing gene product(s) are transplanted to the flank of developing Xenopus laevis embryos in order to establish whether tissue is determined.

تحديد الأنسجة باستخدام زرع رسملة الحيوان (ACT) في الفحص القيطم المورق</em

Many proteins play a dual role in embryonic development. Those that regulate cell fate determination in a specific tissue can also affect the development ...

Live-cell Imaging and Quantitative Analysis of Embryonic Epithelial Cells in Xenopus laevis

Embryonic epithelial cells serve as an ideal model to study morphogenesis where multi-cellular tissues undergo changes in their geometry, such as changes in cell surface area and cell height, and where cells undergo mitosis and migrate. Furthermore, epithelial cells can also regulate morphogenetic movements in adjacent tissues1. A traditional method to study epithelial cells and tissues involve chemical fixation and histological methods to determine cell morphology or localization of particular proteins of interest. These approaches continue to be useful and provide "snapshots" of cell shapes and tissue architecture, however, much remains to be understood about how cells acquire specific shapes, how various proteins move or localize to specific positions, and what paths cells follow toward their final differentiated fate. High resolution live imaging complements traditional methods and also allows more direct investigation into the dynamic cellular processes involved in the formation, maintenance, and morphogenesis of multicellular epithelial sheets. Here we demonstrate experimental methods from the isolation of animal cap tissues from Xenopus laevis embryos to confocal imaging of epithelial cells and simple measurement approaches that together can augment molecular and cellular studies of epithelial morphogenesis.

Live-cell Imaging and Quantitative Analysis of Embryonic Epithelial Cells in Xenopus laevis

Xenopus embryonic epithelia are an ideal model system to study cell behaviors such as polarity development and shape change during epithelial morphogenesis. Traditional histology of fixed samples is increasingly being complemented by live-cell confocal imaging. Here we demonstrate methods to isolate frog tissues and visualize live epithelial cells and their cytoskeleton using live-cell confocal microscopy.

تعيش خلية التصوير والتحليل الكمي من الخلايا الظهارية في الجنينية القيطم المورق</em

Embryonic epithelial cells serve as an ideal model to study morphogenesis where multi-cellular tissues undergo changes in their geometry, such as changes ...

Production of Transgenic Xenopus laevis by Restriction Enzyme Mediated Integration and Nuclear Transplantation

Stable integration of cloned gene products into the Xenopus genome is necessary to control the time and place of expression, to express genes at later stages of embryonic development, and to define how enhancers and promoters regulate gene expression within the embryo. The protocol demonstrated here can be used to efficiently produce transgenic Xenopus laevis embryos. This transgenesis approach involves three parts: 1. Sperm nuclei are isolated from adult X. laevis testis by treatment with lysolecithin, which permeabilizes the sperm plasma membrane. 2. Egg extract is prepared by low speed centrifugation, addition of calcium to cause the extract to progress to interphase of the cell cycle, and a high-speed centrifugation to isolate interphase cytosol. 3. Nuclear transplantation: the nuclei and extract are combined with the linearized plasmid DNA to be introduced as the transgene and a small amount of restriction enzyme. During a short reaction, egg extract partially decondenses the sperm chromatin and the restriction enzyme generates chromosomal breaks that promote recombination of the transgene into the genome. The treated sperm nuclei are then transplanted into unfertilized eggs. Integration of the transgene usually occurs prior to the first embryonic cleavage such that the resulting embryos are not chimeric. These embryos can be analyzed without any need to breed to the next generation, allowing for efficient and rapid generation of transgenic embryos for analyses of promoter and gene function. Adult X. laevis resulting from this procedure also propagate the transgene through the germline and can be used to generate lines of transgenic animals for multiple purposes.

Production of Transgenic Xenopus laevis by Restriction Enzyme Mediated Integration and Nuclear Transplantation

This video protocol demonstrates a method for generating transgenic Xenopus laevis by introduction of transgenes into sperm nuclei followed by nuclear transplantation into unfertilized eggs.

إنتاج المعدلة وراثيا القيطم المورق عن طريق تقييد أنزيم التكامل وساطة وزرع النووية

Stable integration of cloned gene products into the Xenopus genome is necessary to control the time and place of expression, to express genes at later ...

Dissection of Xenopus laevis Neural Crest for in vitro Explant Culture or in vivo Transplantation

The neural crest (NC) is a transient dorsal neural tube cell population that undergoes an epithelium-to-mesenchyme transition (EMT) at the end of neurulation, migrates extensively towards various organs, and differentiates into many types of derivatives (neurons, glia, cartilage and bone, pigmented and endocrine cells). In this protocol, we describe how to dissect the premigratory cranial NC from Xenopus laevis embryos, in order to study NC development in vivo and in vitro. The frog model offers many advantages to study early development; abundant batches are available, embryos develop rapidly, in vivo gain and loss of function strategies allow manipulation of gene expression prior to NC dissection in donor and/or host embryos. The NC explants can be plated on fibronectin and used for in vitro studies. They can be cultured for several days in a serum-free defined medium. We also describe how to graft NC explants back into host embryos for studying NC migration and differentiation in vivo.

Dissection of Xenopus laevis Neural Crest for in vitro Explant Culture or in vivo Transplantation

This protocol describes how to dissect premigratory cranial neural crest (NC) from Xenopus laevis neurulas. These explants can be plated on fibronectin and cultured in vitro, or grafted back into host embryos. This technique allows studying the mechanisms of NC epithelium-to-mesenchyme transition, migration, and differentiation.

تشريح<em&gt; القيطم المورق</em&gt; العصبية كريست ل<em&gt; في المختبر</em&gt; يزدرع الثقافة أو<em&gt; في الجسم الحي</em&gt; زرع

The neural crest (NC) is a transient dorsal neural tube cell population that undergoes an epithelium-to-mesenchyme transition (EMT) at the end of ...

Using plusTipTracker Software to Measure Microtubule Dynamics in Xenopus laevis Growth Cones

Microtubule (MT) plus-end-tracking proteins (+TIPs) localize to the growing plus-ends of MTs and regulate MT dynamics1,2. One of the most well-known and widely-utilized +TIPs for analyzing MT dynamics is the End-Binding protein, EB1, which binds all growing MT plus-ends, and thus, is a marker for MT polymerization1. Many studies of EB1 behavior within growth cones have used time-consuming and biased computer-assisted, hand-tracking methods to analyze individual MTs1-3. Our approach is to quantify global parameters of MT dynamics using the software package, plusTipTracker4, following the acquisition of high-resolution, live images of tagged EB1 in cultured embryonic growth cones5. This software is a MATLAB-based, open-source, user-friendly package that combines automated detection, tracking, visualization, and analysis for movies of fluorescently-labeled +TIPs. Here, we present the protocol for using plusTipTracker for the analysis of fluorescently-labeled +TIP comets in cultured Xenopus laevis growth cones. However, this software can also be used to characterize MT dynamics in various cell types6-8.

Using plusTipTracker Software to Measure Microtubule Dynamics in Xenopus laevis Growth Cones

The MATLAB-based, open source software package, plusTipTracker, can be used to analyze image series of fluorescently-labeled +TIPs to quantify microtubule dynamics.

plusTipTracker باستخدام برنامج لقياس ديناميكية في أنيبيب<em&gt; القيطم المورق</em&gt; المخاريط النمو

Microtubule (MT) plus-end-tracking proteins (+TIPs) localize to the growing plus-ends of MTs and regulate MT dynamics1,2. One of the most well-known and ...