1. Retirer les oeufs de l&#39;incubateur <ol><li> Maintenir à 37 ° C avec une humidité relative de 60% fixé au-dessus. </li><li> Retirer les oeufs, tourner les œufs à 90 ° de telle sorte que la grande base est horizontale. </li></ol> 2. Swab pour stériliser les oeufs <ol><li> Saturer une pile de gaze non stérile avec de l&#39;éthanol à 70%. </li><li> Utilisez deux à trois pièces au coton-tige à 5 œufs. Jeter lors de la gaze est sale. </li></ol> 3. Préparation du site retrait albumine <ol><li> Couper et placer un 1 &quot;x 1&quot; morceau de ruban adhésif 3M juste à gauche de la base afin de protéger la zone où l&#39;albumine sera tirée. </li></ol> 4. Suppression de l&#39;albumine <ol><li> Utilisez le point d&#39;une paire de ciseaux pour faire un petit trou dans le milieu de la bande. </li><li> En utilisant une seringue de 10 cc avec une jauge de 18, 1 pouces aiguille, lentement forage l&#39;aiguille dans le trou fait par les ciseaux. </li><li> Disque de l&#39;aiguille à un angle de 45 ° C vers le bas de l&#39;œuf. </li><li> Inclinez l&#39;aiguille vers le centre et dresser 3 à 4 ml d&#39;albumine. </li></ol> 5. Fenêtrage <ol><li> Coupez un 3 &quot;x 3&quot; morceau de ruban de plastique et l&#39;étirer pour tenir sur le sommet de l&#39;œuf. Étendre les coins de la place autour des extrémités arrondies de la surface horizontale des œufs, en faisant attention à ne pas tirer trop fort. Tirez sur la bande de sorte qu&#39;il est bien serré contre la surface des œufs sans plis. </li><li> En utilisant une paire d&#39;arêtes droites 4 ciseaux de dissection &quot;, tordre un trou dans le centre du fond de la zone où la bande a été placée. Lentement guider la lame inférieure des ciseaux dans l&#39;oeuf étant sûr de garder les astuces contre l&#39;intérieur de le shell. directe de la lame vers le bas et lentement commencer à couper la coquille. Procéder de façon anti-horaire, s&#39;arrêtant juste avant d&#39;atteindre le haut au centre. Enlever la paire de ciseaux et répétez va dans le sens opposé jusqu&#39;à ce que seul un petit peu de la oeuf reste attaché. Vérifiez que l&#39;ovule est fécondé. Fermez la fenêtre. </li></ol> 6. Fermeture, de réouverture et d&#39;étanchéité de l&#39;œuf. <ol><li> Coupez environ un 2-3 &quot;de long par 1 / 2&quot; ruban adhésif large et fermer la fenêtre pour qu&#39;elle s&#39;ajuste dans le trou qui a été coupé. Prenez un autre de 1 x 1 &quot;morceau de ruban adhésif et sceller le trou par lequel l&#39;œuf a été drainé. Utilisez une pince à rouvrir l&#39;œuf pour faire toutes les manipulations. Lorsque vous êtes prêt à retourner les œufs dans l&#39;incubateur, couper un morceau de la bande qui est assez grande pour sceller les fenêtres et couvrir toute la surface horizontale de l&#39;œuf. </li></ol>

<ol>
	<li>Cramer, K. S., Fraser, S. E., Rubel, E. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Dev Biol. 224, 138-151 (2000).</li><li>Cramer, K. S., Bermingham-McDonogh, O., Krull, C. E., Rubel, E. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Dev Biol. 269, 26-35 (2004).</li><li>Cramer, K. S., Cerretti, D. P., Siddiqui, 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=.">.</a> Dev Biol. 295, 76-89 (2006).</li><li>Huffman, K. J., Cramer, K. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Dev Neurobiol. 67, 1655-1668 (2007).</li><li>Krull, C. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Dev Dyn. 229, 433-439 (2004).</li><li>Gerlach-Bank, L. M., Cleveland, A. R., Barald, K. 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> Dev Dyn. 229, 219-230 (2004).</li></ol>

Cette méthode permet des temps de survie à long suivantes manipulations expérimentales. Par exemple, la teinture-étiquetage études ont permis la survie à E10 ou tard dans une étude de la cartographie sort (1). En outre, il a été utilisé pour des études électroporation in ovo qui fournissent l&#39;altération des niveaux d&#39;expression des gènes et de développement requis pour procéder à des étapes ultérieures de développement (2-6). Cette technique de fenêtrage peut être utilisé en combinaison avec une procédure qui...

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		<th>Catalogue Number</th>
		<th>Comment</th>
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<tr>
<td>Rotating incubator</td>
<td>&nbsp;</td>
<td>Profi</td>
<td>&nbsp;</td>
<td>Maintain at 37&#176; Degrees with relative humidity set above 60%</td>
</tr>
<tr>
<td>70 % EtOH</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>gauze</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>3M plastic tape</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>10cc syringe</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>1/egg
</td>
</tr>
<tr>
<td>18G needles</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>1&#189; inch needle, 1/syringe</td>
</tr>
<tr>
<td>Dissection scissors</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>4" sharp straight blades</td>
</tr>
<tr>
<td>Fertilized Eggs</td>
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windowing chicken eggs for developmental studies

L&#39;étude du développement a été grandement facilitée par l&#39;utilisation de l&#39;embryon de poulet comme modèle expérimental. La facilité d&#39;accès de l&#39;embryon a permis de cartographier les expériences destinées cellulaires en utilisant plusieurs méthodes, y compris les poussins de caille chimères et d&#39;étiquetage de teinture focale. En outre, il permet de perturbations moléculaires de plusieurs types, y compris le placement de protéines billes recouvertes et l&#39;introduction d&#39;ADN plasmidique en utilisant l&#39;électroporation in ovo. Ces expériences ont fourni des données importantes sur le développement des systèmes nerveux central et périphérique. Pour beaucoup de ces études, il est nécessaire d&#39;ouvrir la coquille et se refermer sans perturber la croissance de l&#39;embryon. L&#39;embryon peut être examiné à étapes successives de développement par la réouverture de la coquille. Bien qu&#39;il existe plusieurs excellentes méthodes pour l&#39;ouverture des oeufs de poule, dans cet article, nous démontrons une méthode qui a été optimisé pour les durées de survie longue. Dans cette méthode, l&#39;œuf repose sur son côté et une petite fenêtre est coupé dans la coquille. Après la procédure expérimentale, le shell est utilisé pour couvrir l&#39;œuf pour la durée de son développement. Effacer ruban de plastique recouvrant la coquille protège l&#39;embryon et aide à retenir l&#39;hydratation pendant le reste de la période d&#39;incubation. Cette méthode a été utilisée à partir de deux jours d&#39;incubation et a permis la survie à travers les âges mûrs embryonnaire.

Watch this Scientific Journal Video about Windowing Chicken Eggs for Developmental Studies at JoVE.com

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Windowing Chicken Eggs for Developmental Studies

La facilité d&#39;accès de l&#39;embryon a permis de cartographier les expériences destinées cellulaires en utilisant plusieurs méthodes, y compris les poussins de caille chimères et d&#39;étiquetage de teinture focale. Dans cet article, nous démontrons une méthode de préparation d&#39;oeuf qui a été optimisé pour les temps de survie longue.

Oeufs Poulet fenêtrage d&#39;études du développement

The study of development has been greatly aided by the use of the chick embryo as an experimental model.  The ease of accessibility of the embryo has ...

windowing-chicken-eggs-for-developmental-studies

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Biology

27.7K vues.  University of California, Irvine (UCI). La facilité d'accès de l'embryon a permis de cartographier les expériences destinées cellulaires en utilisant plusieurs méthodes, y compris les poussins de caille chimères et d'étiquetage de teinture focale. Dans cet article, nous démontrons une méthode de préparation d'oeuf qui a été optimisé pour les temps de survie longue.

Vidéo: Windowing Chicken Eggs for Developmental Studies

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.

Obtention des oeufs de Xenopus laevis femelles

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, ...

Recherche

Biologie

Xenotransplantation of Human Stem Cells into the Chicken Embryo

The chicken embryo is a classical animal model for studying normal embryonic and fetal development and for xenotransplantation experiments to study the behavior of cells in a standardized in vivo environment. The main advantages of the chicken embryo include low cost, high accessibility, ease of surgical manipulation and lack of a fully developed immune system. Xenotransplantation into chicken embryos can provide valuable information about cell proliferation, differentiation and behavior, the responses of cells to signals in defined embryonic tissue niches, and tumorigenic potential. Transplanting cells into chicken embryos can also be a step towards transplantation experiments in other animal models. Recently the chicken embryo has been used to evaluate the neurogenic potential of human stem and progenitor cells following implantation into neural anlage1-6. In this video we document the entire procedure for transplanting human stem cells into the developing central nervous system of the chicken embryo. The procedure starts with incubation of fertilized eggs until embryos of the desired age have developed. The eggshell is then opened, and the embryo contrasted by injecting dye between the embryo and the yolk. Small lesions are made in the neural tube using microsurgery, creating a regenerative site for cell deposition that promotes subsequent integration into the host tissue. We demonstrate injections of human stem cells into such lesions made in the part of the neural tube that forms the hindbrain and the spinal cord, and into the lumen of the part of the neural tube that forms the brain. Systemic injections into extraembryonic veins and arteries are also demonstrated as an alternative way to deliver cells to vascularized tissues including the central nervous system. Finally we show how to remove the embryo from the egg after several days of further development and how to dissect the spinal cord free for subsequent physiological, histological or biochemical analyses.

In this paper we present a method for transplanting human stem cells into various regions of the central nervous system of the chicken embryo. This provides an in vivo model for assessing the proliferation and differentiation of various types of human stem cells in embryonic tissue environments.

La xénotransplantation de cellules souches humaines dans l&#39;embryon de poulet

The chicken embryo is a classical animal model for studying normal embryonic and fetal development and for xenotransplantation experiments to study the ...

Mutagenesis and Functional Analysis of Ion Channels Heterologously Expressed in Mammalian Cells

We will demonstrate how to study the functional effects of introducing a point mutation in an ion channel. We study G protein-gated inwardly rectifying potassium (referred to as GIRK) channels, which are important for regulating the excitability of neurons. There are four different mammalian GIRK channel subunits (GIRK1-GIRK4) - we focus on GIRK2 because it forms a homotetramer. Stimulation of different types of G protein-coupled receptors (GPCRs), such as the muscarinic receptor (M2R), leads to activation of GIRK channels. Alcohol also directly activates GIRK channels. We will show how to mutate one amino acid by specifically changing one or more nucleotides in the cDNA for the GIRK channel. This mutated cDNA sequence will be amplified in bacteria, purified, and the presence of the point mutation will be confirmed by DNA sequencing. The cDNAs for the mutated and wild-type GIRK channels will be transfected into human embryonic kidney HEK293T cells cultured in vitro. Lastly, whole-cell patch-clamp electrophysiology will be used to study the macroscopic potassium currents through the ectopically expressed wild-type or mutated GIRK channels. In this experiment, we will examine the effect of a L257W mutation in GIRK2 channels on M2R-dependent and alcohol-dependent activation.

We will demonstrate how to study the effect of a single point mutation on the function of an ion channel.

Mutagenèse et analyse fonctionnelle des canaux ioniques hétérologue exprimée dans les cellules de mammifères

We will demonstrate how to study the functional effects of introducing a point mutation in an ion channel. We study G protein-gated inwardly rectifying ...

Gene Transfer into Older Chicken Embryos by ex ovo Electroporation

The chicken embryo provides an excellent model system for studying gene function and regulation during embryonic development. In ovo electroporation is a powerful method to over-express exogenous genes or down-regulate endogenous genes in vivo in chicken embryos1. Different structures such as DNA plasmids encoding genes2-4, small interfering RNA (siRNA) plasmids5, small synthetic RNA oligos6, and morpholino antisense oligonucleotides7 can be easily transfected into chicken embryos by electroporation. However, the application of in ovo electroporation is limited to embryos at early incubation stages (younger than stage HH20 - according to Hamburg and Hamilton)8 and there are some disadvantages for its application in embryos at later stages (older than stage HH22 - approximately 3.5 days of development). For example, the vitelline membrane at later stages is usually stuck to the shall membrane and opening a window in the shell causes rupture of the vessels, resulting in death of the embryos; older embryos are covered by vitelline and allantoic vessels, where it is difficult to access and manipulate the embryos; older embryos move vigorously and is difficult to control the orientation through a relatively small window in the shell.
In this protocol we demonstrate an ex ovo electroporation method for gene transfer into chicken embryos at late stages (older than stage HH22). For ex ovo electroporation, embryos are cultured in Petri dishes9 and the vitelline and allantoic vessels are widely spread. Under these conditions, the older chicken embryos are easily accessed and manipulated. Therefore, this method overcomes the disadvantages of in ovo electroporation applied to the older chicken embryos. Using this method, plasmids can be easily transfected into different parts of the older chicken embryos10-12.

Gene Transfer into Older Chicken Embryos by ex ovo Electroporation

A method of gene transfer into chicken embryos at later incubation stages (older than Hamburger and Hamilton stage (HH) 22) is described. This method overcomes disadvantages of in ovo electroporation applied to older chicken embryos and is a useful technique to study gene function and regulation at older developmental stages.

Transfert de gènes dans des embryons de poulet âgés par<em&gt; Ex ovo</em&gt; Électroporation

The chicken embryo provides an  excellent model system for studying gene function and regulation during  embryonic development. In ovo electroporation is ...

Separation of Spermatogenic Cell Types Using STA-PUT Velocity Sedimentation

Mammalian spermatogenesis is a complex differentiation process that occurs in several stages in the seminiferous tubules of the testes. Currently, there is no reliable cell culture system allowing for spermatogenic differentiation in vitro, and most biological studies of spermatogenic cells require tissue harvest from animal models like the mouse and rat. Because the testis contains numerous cell types - both non-spermatogenic (Leydig, Sertoli, myeloid, and epithelial cells) and spermatogenic (spermatogonia, spermatocytes, round spermatids, condensing spermatids and spermatozoa) - studies of the biological mechanisms involved in spermatogenesis require the isolation and enrichment of these different cell types. The STA-PUT method allows for the separation of a heterogeneous population of cells - in this case, from the testes - through a linear BSA gradient. Individual cell types sediment with different sedimentation velocity according to cell size, and fractions enriched for different cell types can be collected and utilized in further analyses. While the STA-PUT method does not result in highly pure fractions of cell types, e.g. as can be obtained with certain cell sorting methods, it does provide a much higher yield of total cells in each fraction (~1 x 108 cells/spermatogenic cell type from a starting population of 7-8 x 108 cells). This high yield method requires only specialized glassware and can be performed in any cold room or large refrigerator, making it an ideal method for labs that have limited access to specialized equipment like a fluorescence activated cell sorter (FACS) or elutriator.

The STA-PUT method allows for the separation of different populations of spermatogenic cells based on size and density.

Séparation des types cellulaires de la spermatogenèse Utilisation STA-PUT vitesse de sédimentation

Mammalian spermatogenesis is a complex  differentiation process that occurs in several stages in the seminiferous  tubules of the testes. Currently, there ...

A Guide to Modern Quantitative Fluorescent Western Blotting with Troubleshooting Strategies

The late 1970s saw the first publicly reported use of the western blot, a technique for assessing the presence and relative abundance of specific proteins within complex biological samples. Since then, western blotting methodology has become a common component of the molecular biologists experimental repertoire. A cursory search of PubMed using the term &#8220;western blot&#8221; suggests that in excess of two hundred and twenty thousand published manuscripts have made use of this technique by the year 2014. Importantly, the last ten years have seen technical imaging advances coupled with the development of sensitive fluorescent labels which have improved sensitivity and yielded even greater ranges of linear detection. The result is a now truly Quantifiable Fluorescence based Western Blot (QFWB) that allows biologists to carry out comparative expression analysis with greater sensitivity and accuracy than ever before. Many &#8220;optimized&#8221; western blotting methodologies exist and are utilized in different laboratories. These often prove difficult to implement due to the requirement of subtle but undocumented procedural amendments. This protocol provides a comprehensive description of an established and robust QFWB method, complete with troubleshooting strategies.

The advancement of western blotting using fluorescence has allowed detection of subtle changes in protein expression enabling quantitative analyses. Here we describe a robust methodology for detection of a range of proteins across a variety of species and tissue types. A strategy to overcome common technical problems is also provided.

Un Guide to Modern quantitative fluorescente Western blot avec des stratégies de dépannage

The late 1970s saw the first publicly reported use of the western blot, a technique for assessing the presence and relative abundance of specific proteins ...

Tracking and Quantifying Developmental Processes in C. elegans Using Open-source Tools

Quantitatively capturing developmental processes is crucial to derive mechanistic models and key to identify and describe mutant phenotypes. Here protocols are presented for preparing embryos and adult C. elegans animals for short- and long-term time-lapse microscopy and methods for tracking and quantification of developmental processes. The methods presented are all based on C. elegans strains available from the Caenorhabditis Genetics Center and on open-source software that can be easily implemented in any laboratory independently of the microscopy system used. A reconstruction of a 3D cell-shape model using the modelling software IMOD, manual tracking of fluorescently-labeled subcellular structures using the multi-purpose image analysis program Endrov, and an analysis of cortical contractile flow using PIVlab (Time-Resolved Digital Particle Image Velocimetry Tool for MATLAB) are shown. It is discussed how these methods can also be deployed to quantitatively capture other developmental processes in different models, e.g., cell tracking and lineage tracing, tracking of vesicle flow.

Tracking and Quantifying Developmental Processes in C. elegans Using Open-source Tools

Here it is shown how to track and quantify developmental processes in C. elegans. The methods presented are based on open-source tools that can be easily implemented. It is demonstrated how to reconstruct 3D cell-shape models, how to manually track subcellular structures, and how to analyze cortical contractile flow.

Suivi et quantification des processus de développement des<em&gt; C. elegans</em&gt; Utilisation des outils open-source

Quantitatively capturing developmental processes is crucial to derive mechanistic models and key to identify and describe mutant phenotypes. Here ...

Laser-assisted Lentiviral Gene Delivery to Mouse Fertilized Eggs

Lentiviruses are efficient vectors for gene delivery to mammalian cells. Following transduction, the lentiviral genome is stably incorporated into the host chromosome and is passed on to progeny. Thus, they are ideal vectors for creation of stable cell lines, in vivo delivery of indicators, and transduction of single cell fertilized eggs to create transgenic animals. However, mouse fertilized eggs and early stage embryos are protected by the zona pellucida, a glycoprotein matrix that forms a barrier against lentiviral gene delivery. Lentiviruses are too large to penetrate the zona and are typically delivered by microinjection of viral particles into the perivitelline cavity, the space between the zona and the embryonic cells. The requirement for highly skilled technologists and specialized equipment has minimized the use of lentiviruses for gene delivery to mouse embryos. This article describes a protocol for permeabilizing the mouse fertilized eggs by perforating the zona with a laser. Laser-perforation does not result in any damage to embryos and allows lentiviruses to gain access to embryonic cells for gene delivery. Transduced embryos can develop into blastocyst in vitro, and if implanted in pseudopregnant mice, develop into transgenic pups. The laser used in this protocol is effective and easy to use. Genes delivered by lentiviruses stably incorporate into mouse embryonic cells and are germline transmittable. This is an alternative method for creation of transgenic mice that requires no micromanipulation and microinjection of fertilized eggs.

Mouse fertilized eggs and early stage embryos are protected by the zona pellucida, a glycoprotein matrix that forms a barrier against gene delivery. This article describes a protocol for perforating the zona with a laser to transduce embryonic cells with lentiviral vectors and to create transgenic mice.

Oeufs fécondés de livraison assistée par laser des gènes gène aux souris

Lentiviruses are efficient vectors for gene delivery to mammalian cells. Following transduction, the lentiviral genome is stably incorporated into the ...

Measuring Photophysiology of Attached Stage of Colacium sp. by a Cuvette-Type Fast Repetition Rate Fluorometer

Fast repetition rate fluorometer (FRRf) is a beneficial method for measuring photosystem II (PSII) photophysiology and primary productivity. Although FRRf can measure PSII absorption cross-section (&#963;PSII), maximum photochemical efficiency (Fv/Fm), effective photochemical efficiency (Fq&#8242;/Fm&#8242;), and non-photochemical quenching (NPQNSV) for various eukaryotic algae and cyanobacteria, almost all FRRf studies to date have focused on phytoplankton. Here, the protocol describes how to measure PSII photophysiology of an epizoic alga Colacium sp.&#160;Ehrenberg 1834 (Euglenophyta), in its attached stage (attached to zooplankton), using cuvette-type FRRf. First, we estimated the effects of substrate zooplankton (Scapholeberis mucronata O.F. M&#252;ller 1776, Cladocera, Daphniidae) on baseline fluorescence and &#963;PSII, Fv/Fm, Fq&#8242;/Fm&#8242;, and NPQNSV of planktonic Colacium sp. To validate this methodology, we recorded photophysiology measurements of attached Colacium sp. on S. mucronata and compared these results with its planktonic stage. Representative results showed how the protocol could determine the effects of calcium (Ca) and manganese (Mn) on Colacium sp. photophysiology and identify the various effects of Mn enrichment between attached and planktonic stages. Finally, we discuss the adaptability of this protocol to other periphytic algae.

Measuring Photophysiology of Attached Stage of Colacium sp. by a Cuvette-Type Fast Repetition Rate Fluorometer

Fast repetition rate fluorometer (FRRf) is a beneficial method for measuring photosystem II photophysiology and primary productivity. Here we describe a protocol to measure PSII photophysiology of epizoic alga, Colacium sp. on substrate zooplankton using cuvette-type FRRf.

Mesure de la photophysiologie du stade attaché de Colacium sp. par un fluoromètre à taux de répétition rapide de type cuvette

Fast repetition rate fluorometer (FRRf) is a beneficial method for measuring photosystem II (PSII) photophysiology and primary productivity. Although FRRf ...

Avancement des techniques ARNi chez Trichogramma dendrolimi pour l’analyse de la fonction des gènes

RNA Interference in the Egg Parasitoid, Trichogramma dendrolimi Matsumura

The egg parasitoids, Trichogramma spp, are recognized as efficient biological control agents against various lepidopteran pests in agriculture and forests. The immature stages of Trichogramma offspring develop within the host egg, exhibiting remarkable diminutiveness (approximately 0.5 mm in adult length). RNA-interference (RNAi) methodology has emerged as a crucial tool for elucidating gene functions in numerous organisms. However, manipulating RNAi in certain small parasitoid species, such as Trichogramma, has generally posed significant challenges. In this study, we present an efficient RNAi method in Trichogramma denrolimi. The outlined procedure encompasses the acquisition and isolation of individual T. dendrolimi specimens from host eggs, the design and synthesis of double-stranded RNA (dsRNA), the in vitro transplantation and cultivation of T. dendrolimi pupae, the micro-injection of dsRNA, and the subsequent assessment of target gene knockdown through RT-qPCR analysis. This study furnishes a comprehensive, visually detailed procedure for conducting RNAi experiments in T. dendrolimi, thereby enabling researchers to investigate the gene regulation in this species. Furthermore, this methodology is adaptable for RNAi studies or micro-injections in other Trichogramma species with minor adjustments, rendering it a valuable reference for conducting RNAi experiments in other endoparasitic species.

Pleins feux sur l’auteur : Étude de la parthénogenèse thélytokous induite par Wolbachia et du développement d’une boîte à outils génétique par interférence ARN

The manipulation of RNA interference (RNAi) presents a formidable challenge in many parasitoid species with diminutive size, such as Trichogramma wasps. This study delineated an efficient RNAi method in Trichogramma denrolimi. The present methodology provides a robust model for investigating gene regulation in Trichogramma wasps.