ويدعم هذا العمل عن طريق منحة مقدمة من لجنة نهر الميكونج لFS م.

<ol>
	<li>Furutani-Seiki, M., Sasado, T., Morinaga, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+systematic+genome-wide+screen+for+mutations+affecting+organogenesis+in+Medaka,+Oryzias+latipes.">A systematic genome-wide screen for mutations affecting organogenesis in Medaka, Oryzias latipes.</a> Mech Dev. 121, 647-658 (2004).</li><li>Furutani-Seiki, M., Wittbrodt, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Medaka+and+zebrafish,+an+evolutionary+twin+study.">Medaka and zebrafish, an evolutionary twin study.</a> Mech Dev. 121, 629-6237 (2004).</li><li>Hirose, Y., Varga, Z. M., Kondoh, H., Furutani-Seiki, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Single+cell+lineage+and+regionalization+of+cell+populations+during+Medaka+neurulation.">Single cell lineage and regionalization of cell populations during Medaka neurulation.</a> Development. 131, 2553-2563 (2004).</li><li>Iwamatsu, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stages+of+normal+development+in+the+medaka+Oryzias+latipes.">Stages of normal development in the medaka Oryzias latipes.</a> Zool Sci. 11, 825-839 (1994).</li><li>Cope, J., Fluck, R., Nicklas, L., Plumhoff, L. A., Sincock, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+stellate+layer+and+rhythmic+contractions+of+the+Oryzias+latipes+embryo.">The stellate layer and rhythmic contractions of the Oryzias latipes embryo.</a> J Exp Zool. 254, 270-275 (1990).</li><li>Brend, T., Holley, 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=Zebrafish+Whole+Mount+High-Resolution+Double+Fluorescent+In+Situ+Hybridization.">Zebrafish Whole Mount High-Resolution Double Fluorescent In Situ Hybridization.</a> J Vis Exp. , (2009).</li></ol>

الإعلان عن أي تضارب في المصالح.

نحن في هذا الفيديو لشرح كيفية dechorionate وتنفيذ transplanataion الخلية على الأجنة الميداكا. هذا هو أسلوب قوية لإنتاج أجنة خيالية لدراسة الجينات / وظيفة البروتين خلال التنمية ، فضلا عن توضيح الحكم الذاتي من الجين / بروتين في السؤال. الميداكا تشكل نموذجا مفيدا الفقاريات النظام لهذا الأسلوب نظرا لخرائط مصير راسخة والقروض التي تقدمها لهم بشكل جيد للشفافية في مجال التصوير في الوقت الحقيقي الجسم الحي. ويمكن الجمع بين زرع مع microinjection (كما هو موضح في &quot;Microinjection الأجنة الميداكا&quot; البروتوكول المرافق له إن الرب) بحيث يمكن للسلوك الخلايا المزروعة ملاحظتها بسهولة.

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		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>Embryo medium</td>
<td>Reagent</td>
<td>Made in-house</td>
<td>N/A</td>
<td>200ml 50X stock solution, 1ml 1%methyleneblue in H2O/10 liter RO water (50X stock solution: NaCl 14.7g, KCl 0.6g, CaCl2 2H2O 2.4g, MgSO4 7H2O 4.0g/1 litre RO water.)</td>
</tr>
<tr>
<td>Micro-dissecting forceps</td>
<td>Tools</td>
<td>55 INOX A.DUMONT&amp;FILS</td>
<td>N/A</td>
<td>Very sharp fine tips for removal of chorion.</td>
</tr>
<tr>
<td>Fine waterproof sandpaper - p2000 grit size</td>
<td>Tools</td>
<td>Hermes Abrasives Ltd.</td>
<td>N/A</td>
<td>Very fine grit size for rolling/cleaning embryos with chorions.</td>
</tr>
<tr>
<td>3% methylcellulose</td>
<td>Reagent</td>
<td>Sigma</td>
<td>M 0512</td>
<td>High viscosity for holding embryos in place during transplantation.</td>
</tr>
<tr>
<td>1X BSS</td>
<td>Reagent</td>
<td>Made in-house</td>
<td>N/A</td>
<td>20XBSS: 130g NaCl, 8g KCl, 4g MgSO4.7H2O, 4g CaCl2.2H2O, and 10mg Phenol Red in 1L MilliQ water and autoclave; 500mM Hepes in MilliQ water autoclaved. Add 25ml 20XBSS and 15ml 500ml Hepes pH7.0, fill up to 500ml and filter sterilize before use.</td>
</tr>
<tr>
<td>Penicillin-streptomycin</td>
<td>Reagent</td>
<td>Gibco</td>
<td>15140-122</td>
<td>Added to BSS when incubating dechorionated embryos.</td>
</tr>
<tr>
<td>Pronase</td>
<td>Reagent</td>
<td>Calbiochem</td>
<td>53702</td>
<td>For dechorionation.</td>
</tr>
<tr>
<td>Hatching enzyme</td>
<td>Reagent</td>
<td>Made in-house</td>
<td>N/A</td>
<td>For dechorionation.</td>
</tr>
<tr>
<td>Tricaine mesilate (TMS)</td>
<td>Reagent</td>
<td>Sigma</td>
<td>A-5040</td>
<td>400mg tricaine in 97.9ml distilled water and 2.1ml 1M Tris, pH adjusted to 7; 4.2ml of this solution in 100ml clean tank water.</td>
</tr>
<tr>
<td>3% ultra-low gelling temp. agarose</td>
<td>Reagent</td>
<td>Sigma</td>
<td>A-2576</td>
<td>Type IX-A. Used during embedding of embryos for observation.</td>
</tr>
<tr>
<td>Petri dish culture chamber</td>
<td>Tool</td>
<td>Iwaki, Asahi Techno Glass Corp.</td>
<td>11-004-008</td>
<td>Iwaki glass base dish 35mm with 12mm window. Used during embedding of embryos for observation.</td>
</tr>
<tr>
<td>Micromanipulator</td>
<td>Equipment</td>
<td>Narishige</td>
<td>N/A</td>
<td>Model MN151. For removal and insertion of cells during transplantation.</td>
</tr>
<tr>
<td>Borosilicate glass capillaries</td>
<td>Tool</td>
<td>Harvard Apparatus</td>
<td>GC100-10T</td>
<td>For making transplantation needles.</td>
</tr>
<tr>
<td>Flaming/Brown micropipette puller</td>
<td>Equipment</td>
<td>Sutter Instrument Co.</td>
<td>Model P-97 </td>
<td>For making transplantation needles.</td>
</tr>		</tbody>
		</table>
		</div>

dechorionation of medaka embryos and cell transplantation for the generation of chimeras

الميداكا صغيرة أسماك المياه العذبة وضع البيض على حد سواء التي تتيح التحليلات الجينية والجنينية ، وهي واحدة من الكائنات الثلاثة النموذج في الفقاريات والتي نفذت على نطاق الجينوم النمط الظاهري يحركها شاشات متحولة إلى 1. اختلاف في تداخل الجينات الوظيفية ذات الصلة بين الميداكا الزرد ويسمح تحديد الظواهر الجديدة التي يتم التحقق من هويته في نوع واحد 2 ، وبالتالي الميداكا الزرد ومكملة للتشريح الجيني للجينوم الفقريات وظائف. التلاعب الميداكا الأجنة ، مثل dechorionation والأجنة المتصاعدة للتصوير وزرع الخلايا ، والإجراءات الأساسية للعمل على حد سواء الميداكا والزرد في المختبر. زرع الخلايا يفحص الحكم الذاتي خلية من الطفرات الميداكا. يتم إنشاؤها بواسطة زرع خلايا الوهم المسمى من أجنة المانحة في الأجنة المتلقي غير المسماة. يمكن زرع الخلايا المانحة إلى مناطق محددة من أجنة المستفيدة على أساس خرائط مصير 3 بحيث يمكن أن تكون متكاملة من استنساخ الخلايا التي تم زرعها في الأنسجة من خلال الاهتمام بالتنمية. وتشارك أكثر بسبب المشيماء الثابت والأجنة لينة ، والتلاعب في الأجنة في الميداكا من الزرد. في هذا الفيديو ، وتبين لنا إجراءات تفصيلية لمعالجة الأجنة الميداكا.

Watch this Scientific Journal Video about Dechorionation of Medaka Embryos and Cell Transplantation for the Generation of Chimeras at JoVE.com

Dechorionation of Medaka Embryos and Cell Transplantation for the Generation of Chimeras

وتشارك أكثر بسبب المشيماء الثابت والأجنة لينة ، والتلاعب في الأجنة في الميداكا من الزرد. هذا الفيديو يظهر خطوة بخطوة إجراءات لكيفية التعامل مع الأجنة الميداكا ، بما في ذلك dechorionation ، agarose المتصاعد في التصوير وزرع الخلايا لانتاج الوهم. هذه الإجراءات ضرورية لاستخدام الميداكا والزرد في مختبر للاستفادة الكاملة من ميزات التكامل بينهما للتشريح وظائف الجينوم الوراثي للالفقاريات.

Dechorionation الجنين الميداكا وزرع الخلايا لتوليد الوهم

Medaka is a small egg-laying freshwater fish that allows both genetic and embryological analyses and is one of the three vertebrate model organisms in ...

dechorionation-medaka-embryos-cell-transplantation-for-generation

Research

JoVE Journal

Biology

17.7K Views.  University of Bath. وتشارك أكثر بسبب المشيماء الثابت والأجنة لينة ، والتلاعب في الأجنة في الميداكا من الزرد. هذا الفيديو يظهر خطوة بخطوة إجراءات لكيفية التعامل مع الأجنة الميداكا ، بما في ذلك dechorionation ، agarose المتصاعد في التصوير وزرع الخلايا لانتاج الوهم. هذه الإجراءات ضرورية لاستخد...

Video: Dechorionation of Medaka Embryos and Cell Transplantation for the Generation of Chimeras

Isolation and Transplantation of Hematopoietic Stem Cells (HSCs)

Isolation and Transplantation of Hematopoietic Stem Cells HSCs

I am Christina Ceso. I am a postdoc in David's Den lab and I work on the hematopoietic stem cells. Today we are going to purify long-term recuperating hematopoietic stem cells and we'll transplant them into a mouse.We start by spraying the mice with alcohol so that first of all, the mind starts sterilized and also the hair doesn't interfere with the dissection. We use PBS with 2%serum for the dissection. I cut the back skin and I pull the skin apart in order to expose the tissue.In order to isolate the tibia, I hold the tibia with tweezers. I cut the tendon on top of the knee and I cut the muscles below the knee and after that I cut through the knee so that the TBI is not connected to the rest of the limb anymore and I pull in order to isolate it. I then hold the TB upside down and with the scissors I separate the foot from the tibia In order to obtain the femur.I cut the muscles around the femur and then I dislocate the femur from the hip. In order to isolate the hip, I cut the muscle around the hip bone on the side of the tail of the mouse and then I pull the hip away from the body of the mouth In order to isolate the spine. I cut through the tail as close as I can to the beginning of the back and then I cut on the two sides of the spine and below the spine, trying to stay as close as possible to the spine so that the peritoneum is not cut and the intestine is left untouched.A first round of cleaning of the bones is done with a scalpel, which is used to scrape the bone, the muscles away from the bone. The scalpel is good to clean the femurs, the hip and the spine. In order to clean the tibia, I hold them with forceps and I use the forceps to remove as much tissue as possible.A second round of cleaning is done using clean wipe to completely clean the bones outta the muscle, and I use the F wipe to clean the tibia, the femurs and the hips. So this is how bones look. After cleaning, I prefer 50 amount tubes with filters on top and I transfer the bones into the mortar.I add the section media and I crush the bones ask of the first round of crashing of the bones. I piped the mixture in order to release as many styles as possible into solution and reduce clumps. I transferred the mixture on the tubes through the filters and this is what the bone fragments look like after the first round of crushing.So I add more dissection medium to the bone fragments and I flash them again. I transferred the seline mixture to the tubes through the filters and at this point the remaining bone fragments are white and there is no bone marrow left. The tubes are filled with PBS 2%serum and in order to have them all with the same weight so that they're balanced in the centrifuge, but also in order to wash the filters so that we obtain as many cells as possible, I then centrifuge the cell mixture and after centrifugation, the palt includes the bone marrow cells.I aspirate the medium and I move back and forward the tube on the rack so that the pelle is becomes loose and fewer clamps are formed. When I add medium, at this point I add one ml of medium per tube and I ics since I'm sorting hematopoietic stem cells. Later on, I'm going to store an ALI output of total bone marrow sizes at this point, which I will use later for the fact single color control.I add lineage antibody cocktail. I ordered the samples to mix them well and I invaded four degrees for 15 minutes. In the meantime, I start preparing the columns for the lineage division.I put the columns on the magnet and I prepare Ian tubes under the columns. I also prepared the gas PBS using aster flip filter and attaching it to the vacuum so that all the bubbles of air move in the top part of the filter. I then add three ml of the gas DBS to each column in order for the column to become wet.After the incubation with the antibodies, I add medium to the cell samples and I centrifuge them in order to remove the excess of antibodies. After the centrifugation, the stain cells are in the pallet. I aspirate the medium and I suspend the pallet in one mile of the gas PBSI Add the strip tab beans, I mix the cells and I incubate for 15 minutes at four degrees.After the incubation, I put new elucian tubes under the columns. I add two ml of PBS to each tube with the cells and I transferred the cell mixture to the column through a 40 micron filter. I wash the tubes with more medium in order to collect all the cells remaining and I apply the remaining medium through the filters to the columns.The progenitor cells lineage low are alluded into the collection views. I pulled the luted samples and I sent tofu them. So after the centrifugation, the depleted cells are in a white pate.I aspirate the medium and re suspend the cells. I store an adequate of the depleted cells and I add the antibodies to the cell mixture for the sorting and also to all the single color controls. The antibodies are incubated in that with the size for 15 minutes in the fridge.After the ation, I add medium to the cells and and centrifuge them to remove the ex excess of antibodies. After the centrifugation, the cells are in the pt, I aspirate the media that I suspend the cells and I transfer the cells into fox tubes with a blue filter. At this point, the cells are ready to be sorted.I place, I place the mouse under a heating lamp for a few minutes so that the veins dilate and they are more easily seen. When preparing the syringe, you have to be careful to eliminate all the bubbles from the, the mixture that is in the syringe and then you bend the needle at 90 degrees. I put the mouse under a glass cup with a weight on top so that it can run away.I sterilize the tail with the alcohol pad so that the site of injection is sterile, but also it's easier to identify the vein. If you look at the tail of the mouse from the top in the middle and top of the tail, there is an artery while on the two sides there are the two veins and we inject the cells in one of the two veins. I insert the needle into the vein and I inject following injection.It is to wait for a couple of seconds before removing the needle, the needle, and after that I clean the side of injection. This is a representation of the syringe with the ben needle bent at 90 degrees with the knee, the at this ankle compared to the tail, which makes the injection the easiest. When you injecting the tail of the mouse, you have to keep in mind that the tail vein is extremely superficial, so really this is the orientation of the needle compared to the tail.And it looks like you will just keep sliding on top of the tail, but actually you will get into the tail then. I am Christina Ceso. I am a post in David Kaden lab, and I work on the hematopoietic stem cells.I usually use for animals to start with, and I had more variability at the beginning, but once you become consistent with your methods, I consistently get about 50, 000 to 60, 000 stem cells out for mice. I did my PhD in London with Dr.Fiona Wat working on derma stem cells. After that, I just wanted to have a wider knowledge of adult stem cells in various tissues, and so I decided to move to David Kaden lab to work on hematopoietic stem cells, mainly because the things that are known about hematopoietic stem cells are the things that are not known for the epidermic stem cells and a number of assays that can be done with epi.Epidermal stem cells are not really done yet with the hematopoietic stem cells, and so at this point I'm trying to put together the, the knowledge from the two different fields and ultimately I'm interested in the study of the mechanism to regulate adult tissue sensors in general, so not just the epidermis or the stem cells, but also different tissues because there are, there are similar mechanism that is, it's always the same genes that are involved in the regulation that just interact with each other in different ways, and it's just interesting to understand what makes each stem cell be a stem, but then ultimately a stem cell in a different tissue. So giving rise to a different protein.

العزلة وزرع الخلايا الجذعية المكونة للدم (HSCs)

Dissection of 6.5 dpc Mouse Embryos

Analysis of gene expression patterns during early stages of mammalian embryonic development can provide important clues about gene function, cell-cell interaction and signaling mechanisms that guide embryonic patterning. However, dissection of the mouse embryo from the decidua shortly after implantation can be a challenging procedure, and detailed step-by-step documentation of this process is lacking.

Here we demonstrate how post-implantation (6.5 dpc) embryos are isolated by first dissecting the uterus of a pregnant mouse (detection of the vaginal plug was designated day 0.5 poist coitum) and subsequently dissecting the embryo from maternal decidua. The dissection of Reichert's membrane is described as well as the removal of the ectoplacental cone.

Isolation of postimplantation-stage embryos allows one to study gene patterning and analyze cell-lineage decision making processes during embryonic development, but proper dissection of the early embryo can be challenging. This protocol describes a method for isolating early primitive-streak-stage embryos (~6.5 days post coitum [dpc]).

تشريح 6.5 أجنة الفئران DPC

Analysis of gene expression patterns during early stages of mammalian embryonic development can provide important clues about gene function, cell-cell ...

Tracheotomy: A Method for Transplantation of Stem Cells to the Lung

Lung disease is a leading cause of death and likely to become an epidemic given increases in pollution and smoking worldwide. Advances in stem cell therapy may alleviate many of the symptoms associated with lung disease and induce alveolar repair in adults. Concurrent with the ongoing search for stem cells applicable for human treatment, precise delivery and homing (to the site of disease) must be reassured for successful therapy. Here, I report that stem cells can safely be instilled via the trachea opening a non-stop route to the lung. This method involves a skin incision, caudal insertion of a cannula into and along the tracheal lumen, and injection of a stem cell vehicle mixture into airways of the lung. A broad range of media solutions and stabilizers can be instilled via tracheotomy, resulting in the ability to deliver a wider range of cell types. With alveolar epithelium confining these cells to the lumen, lung expansion and negative pressure during inhalation may also assist in stem cell integration. Tracheal delivery of stem cells, with a quick uptake and the ability to handle a large range of treatments, could accelerate the development of cell-based therapies, opening new avenues for treatment of lung disease.

Significant breakthroughs in stem cell identification are continuously being made. To translate these discoveries, however, novel methods for cellular delivery must be devised. Here I report that the airways provide a safe route for stem cell transplantation to the lungs.

القصبة الهوائية : وهناك طريقة لزرع الخلايا الجذعية في الرئة

Lung disease is a leading cause of death and likely to become an epidemic given increases in pollution and smoking worldwide. Advances in stem cell ...

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

Generation of Human CD40-activated B cells

CD40-activated B cells (CD40-B cells) have been identified as an alternative source of immuno-stimulatory antigen-presenting cells (APC) for cancer immunotherapy 1-3. Compared to Dendritic cells (DCs), the best characterized APC, CD40-B cells have several distinct biological and technical properties. Similar to DCs, B cells show an increased expression of MHC and co-stimulatory molecules (Fig.1b), exhibit a strong migratory capacity and present antigen presentation efficiently to T cells, after stimulation with interleukin-4 and CD40 ligand (CD40L). However, in contrast to immature or mature DCs, CD40-B cells express the full lymph node homing triad consisting of CD62L, CCR7/CXCR4, and leukocyte function antigen-1 (LFA1, CD11a/CD18), necessary for homing to secondary lymphoid organs (Fig.1a) 3. CD40-B cells can be generated without difficulties from very small amounts of peripheral blood which can be further expanded in vitro to very large amounts of highly-pure CD40-B cells (&gt;109 cells per patient) from healthy donors as well as cancer patients (Fig.1c,d) 1,4. 
In this protocol we demonstrate how to obtain fully activated CD40-B cells from human PBMC. Key molecules for the cell culture are CD40 ligand, interleukin-4 (IL-4) and cyclosporin A (CsA), which are replenished in a 3-4 day culture cycle. For laboratory purposes CD40-stimulation is provided by NIH/3T3 cells expressing recombinant human CD40 ligand (tCD40L NIH/3T3) 5. To avoid contamination with non-transfected cells, expression of the human CD40 ligand on the transfectants has to be checked regularly (Fig.2). 
After 14 days CD40-B cell cultures consist of more than 95% pure B cells and an expansion of CD40-B cells over 65 days is frequently possible without any loss of function 1, 4. CD40-B cells efficiently take up, process and present antigens to T cells 6. They do not only prime na&#970;ve, but also expand memory T cells 7,8. CD40-activated B cells can be used to study B-cell activation, differentiation and function. Moreover, they represent a promising tool for therapeutic or preventive vaccination against tumors 9.

In this video we present the ex vivo generation and expansion of human CD40-activated B cells (CD40-B) from peripheral blood mononuclear cells (PBMC) by stimulation with CD40 ligand and interleukin-4.

جيل من الخلايا البشرية باء تنشيط CD40

CD40-activated B cells (CD40-B cells) have been identified as an alternative source of immuno-stimulatory antigen-presenting cells (APC) for cancer ...

Generating Chimeric Zebrafish Embryos by Transplantation

One of the most powerful tools used to gain insight into complex developmental processes is the analysis of chimeric embryos. A chimera is defined as an organism that contains cells from more than one animal; mosaics are one type of chimera in which cells from more than one genotype are mixed, usually wild-type and mutant. In the zebrafish, chimeras can be readily made by transplantation of cells from a donor embryo into a host embryo at the appropriate embryonic stage. Labeled donor cells are generated by injection of a lineage marker, such as a fluorescent dye, into the one-cell stage embryo. Labeled donor cells are removed from donor embryos and introduced into unlabeled host embryos using an oil-controlled glass pipette mounted on either a compound or dissecting microscope. Donor cells can in some cases be targeted to a specific region or tissue of the developing blastula or gastrula stage host embryo by choosing a transplantation site in the host embryo based on well-established fate maps.

A step-by-step guide to generating targeted chimeric zebrafish embryos by transplantation at the blastula or gastrula stage.

توليد الأجنة اسماك الزرد همي بواسطة زرع

One of the most powerful tools used to gain insight into complex developmental processes is the analysis of chimeric embryos. A chimera is defined as an ...

Tissue Targeted Embryonic Chimeras: Zebrafish Gastrula Cell Transplantation

Certain fundamental questions in the field of developmental biology can only be answered when cells are placed in novel environments or when small groups of cells in a larger context are altered.  Watching how one cell interacts with and behaves in a unique environment is essential to characterizing cell functions.  Determining how the localized misexpression of a specific protein influences surrounding cells provides insightful information on the roles that protein plays in a variety of developmental processes.  Our lab uses the zebrafish model system to uniquely combine genetic approaches with classical transplantation techniques to generate genotypic or phenotypic chimeras.  We study neuron-glial cell interactions during the formation of forebrain commissures in zebrafish. This video describes a method that allows our lab to investigate the role of astroglial populations in the diencephalon and the roles of specific guidance cues that influence projecting axons as they cross the midline. Due to their transparency zebrafish embryos are ideal models for this type of ectopic cell placement or localized gene misexpression. Tracking transplanted cells can be accomplished using a vital dye or a transgenic fish line expressing a fluorescent protein. We demonstrate here how to prepare donor embryos with a vital dye tracer for transplantation, as well as how to extract and transplant cells from one gastrula staged embryo to another.  We present data showing ectopic GFP+ transgenic cells within the forebrain of zebrafish embryos and characterize the location of these cells with respect to forebrain commissures.  In addition, we show laser scanning confocal timelapse microscopy of Alexa 594 labeled cells transplanted into a GFP+ transgenic host embryo.  These data provide evidence that gastrula staged transplantation enables the targeted positioning of ectopic cells to address a variety of questions in Developmental Biology.

Zebrafish cell transplantation enables the combination of genetics and embryology to generate tissue specific chimeras. This video demonstrates gastrula staged cell transplantations that have allowed our lab to investigate the roles of astroglial populations and specific guidance cues during commissure formation in the forebrain.

الأنسجة الجنينية الوهم المستهدفة : اسماك الزرد المعيدة زرع الخلايا

Certain fundamental questions in the field of developmental biology can only be answered when cells are placed in novel environments or when small groups ...

Preparation of embryos for Electron Microscopy of the Drosophila embryonic heart tube

The morphogenesis of the Drosophila embryonic heart tube has emerged as a valuable model system for studying cell migration, cell-cell adhesion and cell shape changes during embryonic development. One of the challenges faced in studying this structure is that the lumen of the heart tube, as well as the membrane features that are crucial to heart tube formation, are difficult to visualize in whole mount embryos, due to the small size of the heart tube and intra-lumenal space relative to the embryo. The use of transmission electron microscopy allows for higher magnification of these structures and gives the advantage of examining the embryos in cross section, which easily reveals the size and shape of the lumen. In this video, we detail the process for reliable fixation, embedding, and sectioning of late stage Drosophila embryos in order to visualize the heart tube lumen as well as important cellular structures including cell-cell junctions and the basement membrane.

Preparation of embryos for Electron Microscopy of the Drosophila embryonic heart tube

We describe a process for fixation, embedding, sectioning, and imaging of late stage Drosophila embryos for Trasmission Electron Microscopy of the embryonic heart tube. This technique allows for the visualization of the heart tube lumen as well as the basement membrane, which lines the lumen of the heart.

إعداد الأجنة المجهري للإلكترون من ذبابة الفاكهة أنبوب القلب الجنينية

The morphogenesis of the Drosophila  embryonic heart tube has emerged as a valuable model system for studying cell migration, cell-cell adhesion and cell ...

Transplantation of GFP-expressing Blastomeres for Live Imaging of Retinal and Brain Development in Chimeric Zebrafish Embryos

Cells change extensively in their locations and property during embryogenesis. These changes are regulated by the interactions between the cells and their environment. Chimeric embryos, which are composed of cells of different genetic background, are great tools to study the cell-cell interactions mediated by genes of interest. The embryonic transparency of zebrafish at early developmental stages permits direct visualization of the morphogenesis of tissues and organs at the cellular level. Here, we demonstrate a protocol to generate chimeric retinas and brains in zebrafish embryos and to perform live imaging of the donor cells. The protocol covers the preparation of transplantation needles, the transplantation of GFP-expressing donor blastomeres to GFP-negative hosts, and the examination of donor cell behavior under live confocal microscopy. With slight modifications, this protocol can also be used to study the embryonic development of other tissues and organs in zebrafish. The advantages of using GFP to label donor cells are also discussed. 

We demonstrate a protocol to generate chimeric zebrafish embryos for live imaging cellular behavior during embryogenesis.

زرع GFP - معربا عن Blastomeres للتصوير لايف التنمية الشبكية والدماغ في الجنين اسماك الزرد همي

Cells change extensively in their locations and property during embryogenesis. These changes are regulated by the interactions between the cells and their ...

Microinjection of Medaka Embryos for use as a Model Genetic Organism

In this video, we demonstrate the technique of microinjection into one-cell stage medaka embryos. Medaka is a small egg-laying freshwater fish that allows both genetic and embryological analyses and is one of the vertebrate model organisms in which genome-wide phenotype-driven mutant screens were carried out 1, as in zebrafish and the mouse. Divergence of functional overlap of related genes between medaka and zebrafish allows identification of novel phenotypes that are unidentifiable in a single species 2, thus medaka and zebrafish are complementary for genetic dissection of vertebrate genome functions.
To take advantage of medaka fish whose embryos are transparent and develop externally, microinjection is an essential technique to inject cell-tracers for labeling cells, mRNAs or anti-sense oligonucleotides for over-expressing and knocking-down genes of interest, and DNAs for making transgenic lines.

Medaka and zebrafish are complementary for genetic dissection of vertebrate genome functions. This protocol highlights the key points for successful microinjection into medaka embryos, an important technique for embryological and genetic analysis using medaka and zebrafish in a laboratory.

Microinjection الجنين الميداكا لاستخدامها بوصفها كائنا النموذجي الوراثية

In this video, we demonstrate the technique of microinjection into one-cell stage medaka embryos. Medaka is a small egg-laying freshwater fish that allows ...