Name: two-step approach to explore early- and late-stages of organ formation in the avian model: the thymus and parathyroid glands organogenesis paradigm
Uploaded: 2018-06-17T14:00:00
Description: Watch this Scientific Journal Video about Two-step Approach to Explore Early- and Late-stages of Organ Formation in the Avian Model: The Thymus and Parathyroid Glands Organogenesis Paradigm at JoVE.co

The authors are grateful to Ant&#243;nio Cidad&#227;o, Isabel Alcobia, and Leonor Parreira for the critical reading of the manuscript, to Padma Akkapeddi for video narration, and to Vitor Proa from the Histology Service of the Instituto de Histologia e Biologia do Desenvolvimento, Faculdade de Medicina de Lisboa, Universidade de Lisboa, for technical support. We are particularly indebted to Paulo Caeiro and Hugo Silva from the Unidade de audiovisuais (Audiovisual Unit), Faculdade de Medicina de Lisboa, Universidade de Lisboa for their outstanding commitment to the production of this video. We acknowledge Leica Microsystems for kindly providing a stereoscope equipped with video system and to Interaves - Sociedade Agro-Pecu&#225;ria, S.A for contributing with quail fertilized eggs. This work was supported by Faculdade de Medicina de Lisboa, Universidade de Lisboa (FMUL).

All these experiments follow the animal care and ethical guidelines of the Centro Acad&#233;mico de Medicina de Lisboa.
1. Incubation of Fertilized Quail and Chicken Eggs
<ol>
	<li>Incubate Japanese quail (Coturnix coturnix japonica) and chicken (Gallus gallus) fertilized eggs for 3 and 8 days, respectively.
	<ol>
		<li>Place the eggs with the air chamber (egg blunt end) facing up in a humidified incubator at 38 &#176;C.</li>
		<li>Use around 20 quail eggs and 40 chicken eg...

<ol>
	<li>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=The+Nogent+Institute-50+years+of+embryology.">The Nogent Institute-50 years of embryology.</a> Int J Dev Biol. 49 (2-3), 85-103 (2005).</li><li>Chuong, C. M., Wu, P., Plikus, M., Jiang, T. X., Bruce Widelitz, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineering+stem+cells+into+organs:+topobiological+transformations+demonstrated+by+beak,+feather,+and+other+ectodermal+organ+morphogenesis.">Engineering stem cells into organs: topobiological transformations demonstrated by beak, feather, and other ectodermal organ morphogenesis.</a> Curr Top Dev Biol. 72, 237-274 (2006).</li><li>Davey, M. G., Tickle, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+chicken+as+a+model+for+embryonic+development.">The chicken as a model for embryonic development.</a> Cytogenet Genome Res. 117 (1-4), 231-239 (2007).</li><li>Nowak-Sliwinska, P., Segura, T., Iruela-Arispe, M. 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+chicken+chorioallantoic+membrane+model+in+biology,+medicine+and+bioengineering.">The chicken chorioallantoic membrane model in biology, medicine and bioengineering.</a> Angiogenesis. 17 (4), 779-804 (2014).</li><li>Figueiredo, M., Silva, J. 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=Notch+and+Hedgehog+in+the+thymus/parathyroid+common+primordium:+Crosstalk+in+organ+formation.">Notch and Hedgehog in the thymus/parathyroid common primordium: Crosstalk in organ formation.</a> Dev Biol. 418 (2), 268-282 (2016).</li><li>National Research Council. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chapter+6+-+Recent+Advances+in+Developmental+Biology.">Chapter 6 - Recent Advances in Developmental Biology.</a> Scientific Frontiers in Developmental Toxicology and Risk Assessment. , (2000).</li><li>Moura, R. S., Coutinho-Borges, J. P., Pacheco, A. P., Damota, P. O., Correia-Pinto, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=FGF+signalling+pathway+in+the+developing+chick+lung:+expression+and+inhibition+studies.">FGF signalling pathway in the developing chick lung: expression and inhibition studies.</a> PLoS One. 6 (3), e17660 (2011).</li><li>Hamburger, V., Hamilton, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+series+of+normal+stages+in+the+development+of+the+chick+embryo.">A series of normal stages in the development of the chick embryo.</a> J. Morphol. 88, 49-92 (1951).</li><li>Takahashi, Y., Bontoux, M., 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=Epithelio-mesenchymal+interactions+are+critical+for+Quox+7+expression+and+membrane+bone+differentiation+in+the+neural+crest+derived+mandibular+mesenchyme.">Epithelio-mesenchymal interactions are critical for Quox 7 expression and membrane bone differentiation in the neural crest derived mandibular mesenchyme.</a> EMBO J. 10 (9), 2387-2393 (1991).</li><li>Maeda, Y., Noda, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coordinated+development+of+embryonic+long+bone+on+chorioallantoic+membrane+in+ovo+prevents+perichondrium-derived+suppressive+signals+against+cartilage+growth.">Coordinated development of embryonic long bone on chorioallantoic membrane in ovo prevents perichondrium-derived suppressive signals against cartilage growth.</a> Bone. 32 (1), 27-34 (2003).</li><li>Ishida, K., Mitsui, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Generation+of+bioengineered+feather+buds+on+a+reconstructed+chick+skin+from+dissociated+epithelial+and+mesenchymal+cells.">Generation of bioengineered feather buds on a reconstructed chick skin from dissociated epithelial and mesenchymal cells.</a> Dev Growth Differ. 58 (3), 303-314 (2016).</li><li>Le Douarin, N. M., Jotereau, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tracing+of+cells+of+the+avian+thymus+trough+embryonic+life+in+interspecific+chimeras.">Tracing of cells of the avian thymus trough embryonic life in interspecific chimeras.</a> J. Exp. Med. 142, 17-40 (1975).</li><li>Farley, A. M., 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=Dynamics+of+thymus+organogenesis+and+colonization+in+early+human+development.">Dynamics of thymus organogenesis and colonization in early human development.</a> Development. 140, 2015-2026 (2013).</li><li>Gordon, J., Bennett, A. R., Blackburn, C. C., Manley, N. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gcm2+and+Foxn1+mark+early+parathyroid-+and+thymus-specific+domains+in+the+developing+third+pharyngeal+pouch.">Gcm2 and Foxn1 mark early parathyroid- and thymus-specific domains in the developing third pharyngeal pouch.</a> Mech Dev. 103, 141-143 (2001).</li><li>Neves, H., Dupin, E., Parreira, L., 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=Modulation+of+Bmp4+signalling+in+the+epithelial-mesenchymal+interactions+that+take+place+in+early+thymus+and+parathyroid+development+in+avian+embryos.">Modulation of Bmp4 signalling in the epithelial-mesenchymal interactions that take place in early thymus and parathyroid development in avian embryos.</a> Dev Biol. 361 (2), 208-219 (2012).</li><li>Jerome, L. A., Papaioannou, V. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=DiGeorge+syndrome+phenotype+in+mice+mutant+for+the+T-box+gene,+Tbx1.">DiGeorge syndrome phenotype in mice mutant for the T-box gene, Tbx1.</a> Nat Genet. 27 (3), 286-291 (2001).</li><li>Nie, X., Brown, C. B., Wang, Q., Jiao, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inactivation+of+Bmp4+from+the+Tbx1+expression+domain+causes+abnormal+pharyngeal+arch+artery+and+cardiac+outflow+tract+remodeling.">Inactivation of Bmp4 from the Tbx1 expression domain causes abnormal pharyngeal arch artery and cardiac outflow tract remodeling.</a> Cells Tissues Organs. 193 (6), 393-403 (2011).</li><li>Zou, D., Silvius, D., Davenport, J., Grifone, R., Maire, P., Xu, P. X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Patterning+of+the+third+pharyngeal+pouch+into+thymus/parathyroid+by+Six+and+Eya1.">Patterning of the third pharyngeal pouch into thymus/parathyroid by Six and Eya1.</a> Dev Biol. 293 (2), 499-512 (2006).</li><li>Uematsu, 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=Use+of+in+ovo.+chorioallantoic+membrane+engraftment+to+culture+testes+from+neonatal+mice.">Use of in ovo. chorioallantoic membrane engraftment to culture testes from neonatal mice.</a> Comp Med. 64 (4), 264-269 (2014).</li></ol>

A crucial aspect for the success of this method is the quality of both the chicken and quail eggs. Considering the long incubation periods, particularly during the in ovo assay, a good quality of chicken eggs improves viability rates (up to 90%) by the end of the procedure. To achieve this, test eggs from different suppliers. Incubate unmanipulated eggs for long periods (up to 16-17 days) and check their development. To be considered a good quality batch, more than 80% of the embryos should present normal develo...

Avian embryos have been widely used in seminal developmental biology studies. The main advantages of the avian model include the possibility to open the egg, the relatively easy access to the embryo, and the ability to perform micromanipulation. Some examples comprise the classic quail-chicken chimera system for studying cell fate1, application of specific growth factors to the embryo2, and the growth of ectopic cellular structures in the CAM1,3,4.
To get new insights into distinct stages of organ formation, we have recently developed a method which combines grafting techniques with in vitro manipulation of embryonic tissues5. The two-step approach enables the discrimination and exploration of both early- and late-stages of organogenesis, which are often limited due to highly dynamic and complex tissue interactions2. Moreover, the lack of suitable tissue-specific markers frequently limits the use of genetically modified animal models6. This novel method of the two-step approach largely overcomes such limitations.
To study early-stages of organ formation, in the first step, the quail embryonic territory comprising the prospective organ rudiment is isolated and grown in an in vitro organotypic system for 48 h. During this period, pharmacological modulation of specific signaling pathways can be performed by adding drugs to the culture medium5,7. Additionally, cultured tissues can be collected at any stage of in vitro growth and probed for gene-expression (using methods such as qPCR, microarrays, etc.).
In the second step, 48 h-cultured tissues are then grafted onto the CAM of a chicken (c) embryo at embryonic day (E) 8 (cE8) (Hamburger and Hamilton (HH)-stages 33-35)8. The CAM behaves as a vascular supplier of nutrients and allows gas exchanges1,3,4 to grafted tissues enabling its development in ovo for longer periods of time. This experimental step is especially well suited to study late-stages of organogenesis, as fully formed organs can be obtained after 10 days of in ovo development5,9,10,11. Morphological analysis is easily performed by conventional histology to confirm proper organ formation and donor origin of cells can be identified by immunohistochemistry using species-specific antibodies (i.e., MAb Quail PeriNuclear (QCPN)). During the CAM incubation period, grafts can also be grown in the presence of pharmacological agents and collected at any stage of development to evaluate the progression of organogenesis.
The two-step approach, described here in depth, has already been employed in Figueiredo et al.5 to explore the avian parathyroid/thymus common primordium development. Accordingly, the inherent particularities of the embryonic territories and stages of development involved in the organogenesis of the thymus and parathyroid glands will be presented below.
The thymus and parathyroid glands epithelia, though functionally distinct, derive from the endoderm of the pharyngeal pouches (PP)12. In avian, the epithelia of these organs originate from the third and fourth PP endoderm (3/4PP)12, while in mammals the thymic epithelium derives from the 3PP and the epithelium of parathyroid glands derives from the 3PP and 3/4PP in mouse and human, respectively13,14.
One of the earliest stages in the formation of these organs is the emergence of discrete thymus and parathyroid domains in the common primordium. In chicken, these domains can be identified by in situ hybridization, with specific molecular markers, at E4.515. As development proceeds, these organ rudiments individualize and separate from the pharynx, while a thin mesenchymal capsule, formed by neural crest-derived cells, surrounds them (at E5; HH-stage 27). Later on, the thymic epithelium is colonized by hematopoietic progenitor cells (at E6.5; HH-stage 30)12.
As in classical quail-chicken studies1,12, the two-step approach is particularly useful to study the formation of hematopoietic/lymphoid organs, namely the thymus5. As the quail explant, with the organ rudiment, is grafted in the chicken embryo prior to hematopoietic progenitor cell colonization, a chimeric thymus is formed with chicken blood-borne progenitor cells infiltrating a quail thymic epithelial counterpart. This method is, therefore, a useful tool to explore the contribution of hematopoietic cells in the development of the avian hemato/lymphoid system.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Chicken fertilized eggs (Gallus gallus)</td>
			<td>Pintobar, Portugal</td>
			<td></td>
			<td>Poultry farm&#160;</td>
		</tr>
		<tr>
			<td>Quail fertilized eggs (Coturnix coturnix)</td>
			<td>Interaves, Portugal</td>
			<td></td>
			<td>Bird farm&#160;</td>
		</tr>
		<tr>
			<td>15 mL PP centrifuge tubes</td>
			<td>Corning</td>
			<td>430052</td>
			<td></td>
		</tr>
		<tr>
			<td>50 mL PP centrifuge tubes</td>
			<td>Corning</td>
			<td>430290</td>
			<td></td>
		</tr>
		<tr>
			<td>60 x 20 mm pyrex dishes</td>
			<td>Duran group</td>
			<td>21 755 41</td>
			<td></td>
		</tr>
		<tr>
			<td>100 x 20 mm pyrex dishes</td>
			<td>Duran group</td>
			<td>21 755 48</td>
			<td></td>
		</tr>
		<tr>
			<td>Polycarbonate Membrane Insert&#160;</td>
			<td>Corning</td>
			<td>3412</td>
			<td>24 mm transwell with 0.4 mm Pore Polycarbonate Membrane Insert&#160;</td>
		</tr>
		<tr>
			<td>Membrane filter</td>
			<td>Millipore</td>
			<td>DTTP01300</td>
			<td>0.6 mm Isopore membrane filter</td>
		</tr>
		<tr>
			<td>6-well culture plates</td>
			<td>Nunc, Thermo Fisher Scientific</td>
			<td>140675</td>
			<td></td>
		</tr>
		<tr>
			<td>Petri dish, 35 x 10 mm</td>
			<td>Sigma-Aldrich</td>
			<td>P5112&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>Pyrex bowls</td>
			<td></td>
			<td></td>
			<td>from supermarket&#160;</td>
		</tr>
		<tr>
			<td>Transfer pipettes</td>
			<td>Samco Scientific, Thermo Fisher Scientific</td>
			<td>2041S</td>
			<td>2 mL plastic pipet</td>
		</tr>
		<tr>
			<td>Glass pasteur pipette</td>
			<td>normax</td>
			<td>5426015</td>
			<td></td>
		</tr>
		<tr>
			<td>Whatman&#160;qualitative filter paper</td>
			<td>Sigma-Aldrich</td>
			<td>WHA1001090</td>
			<td>Filter paper</td>
		</tr>
		<tr>
			<td>Clear plastic tape</td>
			<td></td>
			<td></td>
			<td>from supermarket&#160;</td>
		</tr>
		<tr>
			<td>Cytokeratin (pan; acidic and basic, type I and II cytokeratins), clone Lu-5</td>
			<td>BMA Biomedicals</td>
			<td>T-1302</td>
			<td></td>
		</tr>
		<tr>
			<td>Cyclopamine hydrate</td>
			<td>Sigma-Aldrich</td>
			<td>C4116</td>
			<td>Pharmacological inhibitor of Hh signalling</td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum</td>
			<td>Invitrogen, Thermo Fisher Scientific</td>
			<td></td>
			<td>Standart FBS</td>
		</tr>
		<tr>
			<td>Paraformaldehyde</td>
			<td>Sigma-Aldrich</td>
			<td>P6148</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin-Streptomycin</td>
			<td>Invitrogen, Thermo Fisher Scientific</td>
			<td>15140-122</td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphate-Buffered Saline (PBS)</td>
			<td>GIBCO, Thermo Fisher Scientific</td>
			<td>10010023</td>
			<td></td>
		</tr>
		<tr>
			<td>QCPN antibody</td>
			<td>Developmental Studies Hybridoma Bank</td>
			<td>QCPN</td>
			<td></td>
		</tr>
		<tr>
			<td>RPMI 1640 Medium, GlutaMAX Supplement&#160;</td>
			<td>GIBCO, Thermo Fisher Scientific</td>
			<td>61870010</td>
			<td></td>
		</tr>
		<tr>
			<td>Bluesil RTV141A/B Silicone Elastomer 1.1Kg Kit</td>
			<td>ELKEM/Silmid</td>
			<td>RH141001KG</td>
			<td>To prepare the back base for petri dish</td>
		</tr>
		<tr>
			<td>Stemolecule LY411575</td>
			<td>Stemgent</td>
			<td>04-0054</td>
			<td>Pharmacological inhibitor of Notch signalling</td>
		</tr>
		<tr>
			<td>TRIzol Reagent</td>
			<td>Invitrogen, Thermo Fisher Scientific</td>
			<td>15596026</td>
			<td>Reagent for total RNA isolation</td>
		</tr>
		<tr>
			<td>Dumont #5 Forceps</td>
			<td>Fine Science Tools</td>
			<td>11251-30&#160;</td>
			<td>Thin forceps</td>
		</tr>
		<tr>
			<td>Extra fine Bonn scissors, curved</td>
			<td>Fine Science Tools</td>
			<td>14085-08</td>
			<td>Curved scissors</td>
		</tr>
		<tr>
			<td>Insect pins&#160;</td>
			<td>Fine Science Tools</td>
			<td>26001-30</td>
			<td></td>
		</tr>
		<tr>
			<td>Micro spatula&#160;</td>
			<td>Fine Science Tools</td>
			<td>10087-12</td>
			<td>Transplantation spoon</td>
		</tr>
		<tr>
			<td>Minutien Pins</td>
			<td>Fine Science Tools</td>
			<td>26002-20</td>
			<td>Microscalpel</td>
		</tr>
		<tr>
			<td>Moria Nickel Plated Pin Holder</td>
			<td>Fine Science Tools</td>
			<td>26016-12</td>
			<td>Holder</td>
		</tr>
		<tr>
			<td>Moria Perforated Spoon</td>
			<td>Fine Science Tools</td>
			<td>10370-17</td>
			<td>Skimmer</td>
		</tr>
		<tr>
			<td>Wecker Eye Scissor</td>
			<td>Fine Science Tools</td>
			<td>15010-11</td>
			<td></td>
		</tr>
		<tr>
			<td>Camera</td>
			<td>Leica Microsystems&#160;</td>
			<td>MC170 HD</td>
			<td></td>
		</tr>
		<tr>
			<td>Stereoscope</td>
			<td>Leica Microsystems&#160;</td>
			<td>Leica M80</td>
			<td></td>
		</tr>
		<tr>
			<td>Microscope</td>
			<td>Leica Microsystems&#160;</td>
			<td>DM2500</td>
			<td></td>
		</tr>
	</tbody>
</table>

two-step approach to explore early- and late-stages of organ formation in the avian model: the thymus and parathyroid glands organogenesis paradigm

The avian embryo, as an experimental model, has been of utmost importance for seminal discoveries in developmental biology. Among several approaches, the formation of quail-chicken chimeras and the use of the chorioallantoic membrane (CAM) to sustain the development of ectopic tissues date back to the last century. Nowadays, the combination of these classical techniques with recent in vitro methodologies offers novel prospects to further explore organ formation.
Here we describe a two-step approach to study early- and late-stages of organogenesis. Briefly, the embryonic region containing the presumptive territory of the organ is isolated from quail embryos and grown in vitro in an organotypic system (up to 48 h). Cultured tissues are subsequently grafted onto the CAM of a chicken embryo. After 10 days of in ovo development, fully formed organs are obtained from grafted tissues. This method also allows the modulation of signaling pathways by the regular administration of pharmacological agents and tissue genetic manipulation throughout in vitro and in ovo developmental steps. Additionally, developing tissues can be collected at any time-window to analyze their gene-expression profile (using quantitative PCR (qPCR), microarrays, etc.) and morphology (assessed with conventional histology and immunochemistry).
The described experimental procedure can be used as a tool to follow organ formation outside the avian embryo, from the early stages of organogenesis to fully formed and functional organs.

The above described protocol details a method that allows the investigation of both early- and late-stages of organogenesis, often limited by complex cellular and molecular interactions.
This method was previously employed in Figueiredo et al.5 to unravel the role of Notch and Hh signaling in the avian parathyroid/thymus common primordium development.
<p class="jove_content" fo:keep-together....

Watch this Scientific Journal Video about Two-step Approach to Explore Early- and Late-stages of Organ Formation in the Avian Model: The Thymus and Parathyroid Glands Organogenesis Paradigm at JoVE.co

Two-step Approach to Explore Early- and Late-stages of Organ Formation in the Avian Model: The Thymus and Parathyroid Glands Organogenesis Paradigm

This article provides an updated approach to the classical quail-chicken chimera system to study organ formation, by combining novel in vitro and in ovo experimental procedures.

The avian embryo, as an experimental model, has been of utmost importance for seminal discoveries in developmental biology. Among several approaches, the ...

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Application of RNAi and Heat-shock-induced Transcription Factor Expression to Reprogram Germ Cells to Neurons in C. elegans

Studying the cell biological processes during converting the identities of specific cell types provides important insights into mechanism that maintain ...

Isolation of Embryonic Tissues and Formation of Quail-Chicken Chimeric Organs Using The Thymus Example

The capacity to isolate embryonic tissues was an essential step for establishing the quail-chicken chimera system, which in turn has provided undisputed ...

Microinjection-based System for In Vivo Implantation of Embryonic Cardiomyocytes in the Avian Embryo

Interpreting the relative impact of cell autonomous patterning versus extrinsic microenvironmental influence on cell lineage determination represents a ...

Whole-Mount In Situ Hybridization in Zebrafish Embryos and Tube Formation Assay in iPSC-ECs to Study the Role of Endoglin in Vascular Development

Vascular development is determined by the sequential expression of specific genes, which can be studied by performing in situ hybridization assays in ...