Este trabalho foi apoiado por uma G. Harold &amp; Leila Y. Mathers Award para HL e uma subvenção NIH (R24 GM080527) para RESCEJ foi um NRSA Pós-Doutorado (NIH F32GM9037222) e está apoiada por uma Scientist Award Desenvolvimento Mentored Pesquisa da National Instituto do Envelhecimento (K01AG04435). Gostaríamos de agradecer aos revisores pelos comentários úteis.

1 Preparação de plasmídeo de DNA, agulhas e injeção Pratos <ol><li> Prepare o DNA de plasmídeo utilizando um kit de alta velocidade ou Maxi Midi e concentra-se o ADN para 2,5 mg / ml usando a precipitação com etanol. O sedimento de DNA deve ser dissolvido em água livre de nuclease desionizada. Armazenar o ADN em 10-20 mL alíquotas a -20 ° C. (Ver Quadro Suplementar 1 para uma lista de vetores disponíveis) </li><li> Faça um prato de injeção utilizando agarose para construir uma calha para a realização de embriões em uma placa de Petri de 100 x 15 mm. <ol><li> Coloque uma lâmina de microscópio de vidro de 75 x 50 em um 100 x 15 mm numa caixa de Petri com um ângulo. Despeje a cerca de 50 ml de 2% de agarose em forma derretida Hidra 24 para a placa de Petri. Alternativamente, despeje a agarose para o prato primeiro e flutuar um &quot;molde microinjeção Fish&quot; no topo. </li><li> Após o ágar ter solidificado, remover a lâmina de vidro, ou o molde. Se foi usada uma lâmina de vidro, corte o excesso de agarose com um bla navalhade formar uma parede. Despeje meio Hydra no prato e usá-lo imediatamente ou armazená-lo a 4 ° C até ser necessário. Nota: pratos de injecção pode ser reutilizado se for armazenado a 4 ° C entre as utilizações. </li></ol></li><li> Puxar agulhas capilares de vidro de borossilicato com um filamento no puxador de micropipeta usando as seguintes condições: 525 aquecer, puxar 75, a velocidade de 100, o tempo da loja 50. as agulhas, pressionando-os para uma estreita faixa de argila, em uma placa de Petri de tal modo que eles são mantida paralelamente ao fundo do prato. </li><li> Para preparar a solução para injecção, combinar 3 uL de solução de ADN de plasmídeo de 2,5 mg / mL com 2 mL de 10% de vermelho de fenol. Vortex a solução brevemente e em seguida girar durante 10 minutos à velocidade máxima numa microcentrífuga para remover quaisquer partículas que podem entupir a agulha. </li><li> Sob um microscópio de dissecação, o clipe de agulha alguns milímetros da ponta com uma pinça para criar uma pequena abertura. Nota: Existe uma certa flexibilidade no tamanho adequado do abertoing porque a pressão pode ser ajustada na etapa 3.3 para acomodar esta variação. </li><li> Colocar a placa de Petri de modo a que é segura a agulha na posição vertical, com a ponta para baixo. Coloque a agulha com cerca de 0,5 ml de solução de injecção por pipetagem do líquido para dentro da extremidade posterior da agulha. Permitir uma acção capilar para puxar a solução para dentro da ponta da agulha. </li></ol> 2 Preparação de embriões para Injeção <ol><li> Em uma base diária digitalizar a cultura tensão Hydra AEP para pólipos produtoras de ovos. Colete estes pólipos e retirá-las em um prato de cultura independente. Observe estes pólipos cada poucas horas durante o dia para monitorar o progresso de formação do ovo. Quando os ovos quebram através do ectoderma e sentar-se em um anel de células ectodérmicas retraídos eles estão prontos para a injeção 25. Colocar estes pólipos em um prato com vários hidra que têm testículos durante pelo menos 1 hora antes da injecção para permitir a fertilização. Hidra &lt;/ Em&gt; machos vai liberar esperma sem qualquer manipulação especial. </li><li> Se as fêmeas são encontrados na colónia AEP com ovos completamente formados, que são aproximadamente de 400 um de diâmetro de 25, ou de 1 a 8, embriões nos estágios de células, também recolher estes injectável. Injetar imediatamente embriões que começaram clivagem. Nota: Não é possível dizer a diferença entre os ovos totalmente formadas e zigotos unicelulares, portanto, estes devem ser incubadas com os homens antes da injeção. </li><li> Antes da injecção, remover a maior parte do tecido parental acima e abaixo do embrião utilizando um bisturi, com uma lâmina de # 15. Deixar apenas o embrião com um pequeno pedaço de coluna corpo ligado, para ser utilizada para manipular o embrião com uma pinça, se necessário. Nota: O tecido que é dissecado a partir do embrião irá regenerar e deve ser guardada para assegurar que permanecem fêmeas na colónia Hidra. </li><li> Utilizando uma pipeta de Pasteur, mover os embriões para o prato de injecção, dispondo-os em paralelo à parede docalha de agarose. </li></ol> 3. microinjecção de ADN do plasmídeo <ol><li> Monte o microinjetor em um suporte magnético que fica em uma chapa de ferro. Montar o suporte da injecção, que é a parte da microinjector que prende a agulha, em um micromanipulador joystick. Monte o manipulador joystick para a chapa de ferro, com um suporte magnético. Coloque esta todo o conjunto para cima no lado direito de um microscópio de dissecção e posiciona o porta-injecção de modo que seja visível no campo de observação. </li><li> Coloque o prato de injecção com embriões sob o microscópio de dissecação, orientada de tal modo que a parede vertical da calha de agarose é para a esquerda. Inserir a agulha no suporte de injecção e diminuir a ponta da agulha para o meio de Hidra no prato. </li><li> Lentamente, rodar o botão da seringa na direcção dos ponteiros do relógio até que o óleo mineral preenche a parte superior da agulha e um fluxo constante de solução de injecção é observado sai da agulha no hidrum meio. Se o fluxo é muito forte, diminuir a pressão, girando o botão para a esquerda. Praticar este passo para obter rotineiramente uma pressão adequada, o que depende do tamanho da abertura da agulha (ou seja, a forma como a agulha foi cortado no passo 1.5). Nota: Se a corrente é muito forte, o embrião não irá sobreviver a injeção. </li><li> Durante a visualização através de um microscópio de dissecação, movimentar o prato de injecção de modo a que o primeiro embrião está no centro do campo. Mover a agulha de modo que ela está a tocar que embrião. Usar o micromanipulador para perfurar o embrião com a agulha. Nota: A parede vertical da calha agarose vai manter o embrião do que está sendo deixado de lado pela agulha. </li><li> Permitir que a solução de injeção a fluir para o embrião 1 ou 2 segundos e, em seguida, remover a agulha rapidamente. Se o embrião tem mais de uma célula, injectar cada célula individual. Use uma pinça para reorientar o embrião para alinhar a célula seguinte, com a ponta da agulha. </li><li> Após o primeiro embryo é injectado, movimentar o prato de modo a que o lado do embrião está na posição de injecção e repetir o procedimento; continuar até que todos os embriões foram injectados. </li></ol> 4 A cultura ea eclosão dos embriões <ol><li> Mover todos os embriões injectados em um prato com algumas hidra que têm testículos (isto é para assegurar que todos os embriões são fertilizados). Incubar os embriões em um 18 ° C incubadora, enquanto eles continuam a embriogênese. </li><li> Uma vez que a fase de cutícula é atingido, mover cada embrião injectado para um poço individual de uma placa de 24 poços cheios com meio de hidra. </li><li> Incubar os embriões injectados durante 2 semanas no escuro a 18 ° C. </li><li> Após o período de incubação duas semanas, verifique cada embrião injetado sob o microscópio de dissecação. Observe quaisquer casos em que o embrião cutícula estágio se soltou do pequeno pedaço de tecido parental eo tecido dos pais tenha regenerado. Remover este pólipo regenerado imediatamente para que ele não é mistaken de um novo filhote. </li><li> Mova o prato de embriões injetados sob a luz do aquário à temperatura ambiente. Verifique as placas de cada dia e recolher filhotes. Novos filhotes será branco porque a cor-de-rosa típico de pólipos Hydra vem da Artemia eles comem. </li><li> Observe os filhotes debaixo de um microscópio de fluorescência para detectar a expressão do transgene. </li></ol>

<ol>
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N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pattern+of+epithelial+cell+cycling+in+hydra.">Pattern of epithelial cell cycling in hydra.</a> Dev Biol. 148, 602-611 (1991).</li><li>Dubel, S., Hoffmeister, S. A., Schaller, H. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differentiation+pathways+of+ectodermal+epithelial+cells+in+hydra.">Differentiation pathways of ectodermal epithelial cells in hydra.</a> Differentiation. 35, 181-189 (1987).</li><li>Khalturin, K., 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=Transgenic+stem+cells+in+Hydra+reveal+an+early+evolutionary+origin+for+key+elements+controlling+self-renewal+and+differentiation.">Transgenic stem cells in Hydra reveal an early evolutionary origin for key elements controlling self-renewal and differentiation.</a> Dev Biol. 309, 32-44 (2007).</li><li>Bosch, T., David, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stem+Cells+of+Hydra+magnipapillata+can+differentiate+into+somatic+cells+and+germ+line+cells.">Stem Cells of Hydra magnipapillata can differentiate into somatic cells and germ line cells.</a> Dev Biol. 121, 182-191 (1987).</li><li>David, C. N., Murphy, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+interstitial+stem+cells+in+hydra+by+cloning.">Characterization of interstitial stem cells in hydra by cloning.</a> Dev Biol. 58, 372-383 (1977).</li><li>Chapman, J. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+dynamic+genome+of+Hydra.">The dynamic genome of Hydra.</a> Nature. 464, 592-596 (2010).</li><li>Boehm, A. M., Bosch, T. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Migration+of+multipotent+interstitial+stem+cells+in+Hydra.">Migration of multipotent interstitial stem cells in Hydra.</a> Zoology (Jena). 115, 275-282 (2012).</li><li>Glauber, K. 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=A+small+molecule+screen+identifies+a+novel+compound+that+induces+a+homeotic+transformation+in+Hydra.">A small molecule screen identifies a novel compound that induces a homeotic transformation in Hydra.</a> Development. 140, 4788-4796 (2013).</li><li>Siebert, S., Anton-Erxleben, F., Bosch, T. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell+type+complexity+in+the+basal+metazoan+Hydra+is+maintained+by+both+stem+cell+based+mechanisms+and+transdifferentiation.">Cell type complexity in the basal metazoan Hydra is maintained by both stem cell based mechanisms and transdifferentiation.</a> Dev Biol. 313, 13-24 (2008).</li><li>Anton-Erxleben, F., Thomas, A., Wittlieb, J., Fraune, S., Bosch, T. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Plasticity+of+epithelial+cell+shape+in+response+to+upstream+signals:+a+whole-organism+study+using+transgenic+Hydra.">Plasticity of epithelial cell shape in response to upstream signals: a whole-organism study using transgenic Hydra.</a> Zoology (Jena). 112, 185-194 (2009).</li><li>Hemmrich, G., 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=Molecular+signatures+of+the+three+stem+cell+lineages+in+Hydra+and+the+emergence+of+stem+cell+function+at+the+base+of+multicellularity.">Molecular signatures of the three stem cell lineages in Hydra and the emergence of stem cell function at the base of multicellularity.</a> Mol Biol Evol. , (2012).</li><li>Juliano, C. 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=PIWI+proteins+and+PIWI-interacting+RNAs+function+in+Hydra+somatic+stem+cells.">PIWI proteins and PIWI-interacting RNAs function in Hydra somatic stem cells.</a> Proc Natl Acad Sci U S A. 111, 337-342 (2014).</li><li>Nishimiya-Fujisawa, C., Kobayashi, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Germline+stem+cells+and+sex+determination+in+Hydra.">Germline stem cells and sex determination in Hydra.</a> Int J Dev Biol. 56, 499-508 (2012).</li><li>Milde, S., 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=Characterization+of+taxonomically+restricted+genes+in+a+phylum-restricted+cell+type.">Characterization of taxonomically restricted genes in a phylum-restricted cell type.</a> Genome Biol. 10, 8 (2009).</li><li>Nakamura, Y., Tsiairis, C. D., Ozbek, S., Holstein, T. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Autoregulatory+and+repressive+inputs+localize+Hydra+Wnt3+to+the+head+organizer.">Autoregulatory and repressive inputs localize Hydra Wnt3 to the head organizer.</a> Proc Natl Acad Sci U S A. 108, 9137-9142 (2011).</li><li>Gee, L., 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=beta-catenin+plays+a+central+role+in+setting+up+the+head+organizer+in+hydra.">beta-catenin plays a central role in setting up the head organizer in hydra.</a> Dev Biol. 340, 116-124 (2010).</li><li>Fraune, S., 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=In+an+early+branching+metazoan,+bacterial+colonization+of+the+embryo+is+controlled+by+maternal+antimicrobial+peptides.">In an early branching metazoan, bacterial colonization of the embryo is controlled by maternal antimicrobial peptides.</a> Proc Natl Acad Sci U S A. 107, 18067-18072 (2010).</li><li>Bridge, D., 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=FoxO+and+stress+responses+in+the+cnidarian+Hydra+vulgaris.">FoxO and stress responses in the cnidarian Hydra vulgaris.</a> PLoS One. 5, e11686 (2010).</li><li>Boehm, 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=FoxO+is+a+critical+regulator+of+stem+cell+maintenance+in+immortal+Hydra.">FoxO is a critical regulator of stem cell maintenance in immortal Hydra.</a> Proc Natl Acad Sci U S A. 109, 19697-19702 (2012).</li><li>Franzenburg, S., 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=MyD88-deficient+Hydra+reveal+an+ancient+function+of+TLR+signaling+in+sensing+bacterial+colonizers.">MyD88-deficient Hydra reveal an ancient function of TLR signaling in sensing bacterial colonizers.</a> Proc Natl Acad Sci U S A. 109, 19374-19379 (2012).</li><li>Dana, C. E., Glauber, K. M., Chan, T. A., Bridge, D. M., Steele, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Incorporation+of+a+horizontally+transferred+gene+into+an+operon+during+cnidarian+evolution.">Incorporation of a horizontally transferred gene into an operon during cnidarian evolution.</a> PLoS One. 7, e31643 (2012).</li><li>Lenhoff, H. M., Lenhoff, H. 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> Hydra: Research Methods. , 29-34 (1983).</li><li>Miller, M. A., Technau, U., Smith, K. M., Steele, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Oocyte+development+in+Hydra+involves+selection+from+competent+precursor+cells.">Oocyte development in Hydra involves selection from competent precursor cells.</a> Dev Biol. 224, 326-338 (2000).</li><li>Lenhoff, H. M., Lenhoff, H. 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> Hydra: Research Methods. , 53-62 (1983).</li></ol>

The authors have nothing to disclose

Hydra rotineiramente reproduz de forma assexuada, mas requer estímulos ambientais para começar gametas produtores. Esses estímulos não são bem definidos para a maioria das espécies de Hydra e podem variar de estirpe para estirpe. Um obstáculo significativo para a produção de Hidra transgénico é a obtenção de embriões numa base regular porque pode ser difícil num ambiente laboratorial para induzir a tornar-se Hydra sexual. A estirpe AEP 25, no entanto, produz ...

Hydra foi usado para estudar a regeneração, formação de padrões, e as células-tronco para cerca de 250 anos 2 Hydra tem um plano corporal simples, que consiste de três linhagens de células:. Epitelial ectodérmica, endodérmica epitelial e intersticial. O corpo tubular é formado por o ectodérmico e linhagens epiteliais da endoderme, cada um dos quais é uma camada única de células. Todas as células epiteliais no corpo da coluna são mitótico. Quando as células epiteliais são deslocados para as extremidades 3, a cabeça (boca e tentáculos) na extremidade bucal ou do pé (disco basal) na extremidade aboral, eles prendem na fase G2 do ciclo celular e alterar o destino da célula 4. As células da linhagem intersticial residem dentro dos interstícios entre as células epiteliais. Esta linhagem é apoiada por células-tronco multipotentes que estão localizados na camada epitelial ectodérmica da coluna corpo 5. As células estaminais intersticiais dar origem a três cel somáticatipos l (nervos, células glandulares, e nematocytes) e as células germinativas 6,7. Como um membro do filo Cnidaria, o grupo irmão de todos os bilaterians, Hydra pode lançar luz sobre os processos biológicos fundamentais compartilhados entre os animais multicelulares. Até recentemente, esses esforços foram impedidos pela falta de métodos confiáveis ​​para a perturbação da função dos genes. No entanto, com o desenvolvimento de metodologia transgênico 1, somos agora capazes de tirar o máximo proveito de Hydra para obter uma melhor compreensão dos mecanismos básicos comuns a animais multicelulares, como a função de células-tronco, regeneração e padronização. Linhas Transgénicas Hydra são estabelecidos por injecção de plasmídeo de ADN em embriões, o que resulta na integração aleatória e expressão quimérico com uma frequência significativa de filhotes. Uma linha com expressão uniforme numa linhagem particular pode ser estabelecida por propagação vegetativa. A capacidade de propagar clonalmente transgenic Hidra linhas é uma vantagem sobre a maioria dos modelos de animais, que pode ser propagado somente por reprodução sexuada. Além disso, as células transgénicas podem ser facilmente rastreados in vivo, devido à transparência do animal e a ausência de proteínas fluorescentes endógenos 8. Nos sete anos desde as primeiras linhas Hydra transgênicas foram feitas 1, essas linhas foram usados ​​para uma variedade de aplicações. Expressão de proteínas fluorescentes em diferentes tipos de células tornou possível controlar o movimento celular, observar as alterações na forma da célula, e rastrear destinos celulares, tanto em condições de tipo selvagem e depois perturbação química 1,5,9-12. Além disso, a expressão de proteínas fluorescentes diferentes nas diversas linhagens de FACS permite o isolamento de populações de células específicas. Esta técnica tem sido utilizada para o seqüenciamento de mRNAs específicos de células-tronco e de linhagem específica pequenos RNAs 13,14. Enquanto o promotor deum dos dois genes da actina Hidra tem sido mais amplamente utilizado, a poucos tipos de células-promotores específicos foram identificados e utilizados para dirigir a expressão da GFP em Hydra 9,11,15,16 transgénico. No futuro, os promotores específicos do tipo de célula irá permitir a observação e recolha de qualquer tipo de célula específico. Além disso, uma abordagem transgénica foi utilizado com sucesso para definir os elementos reguladores que actuam em cis do promotor Wnt3 17. O desenvolvimento de métodos transgênicos em Hydra oferece uma abordagem robusta para testar a função dos genes pela expressão ectópica, superexpressão e knockdown. Os animais transgénicos que foram feitos expressar as proteínas marcadas com fluorescência, de modo a examinar tanto a função e localização celular de 18-20. Além disso, a expressão de ARN de gancho de cabelo na 3&#39;UTR de um transgene GFP leva a knockdown de genes alvo 21,22. Nessas abordagens GFP é necessário para identificare rastrear o tecido transgénico durante a criação da linha transgénica. No entanto, é provável que, em alguns casos, a molécula GFP iria interferir com a função da proteína etiquetada. Um estudo recente demonstra que os genes Hydra podem ser dispostas numa configuração operão, por exemplo, transcrições policistrónico são feitos, os quais são então separados por adição líder trans-splicing e traduzidos em separado 23. Ao colocar um gene que codifica uma proteína ou um gancho de cabelo de ARN na posição a montante de um operão e um gene de proteína fluorescente na posição de jusante, pode-se controlar o tecido transgénico sem ter que marcar o gene que codifica a proteína ou RNA hairpin. Este método tem sido utilizado para expressar um gancho de cabelo de ARN de um operão com DsRed2 configuração, a fim de alcançar gene knockdown 14.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">AEP Hydra Strain</td>
			<td style="width:112px;">NA</td>
			<td style="width:119px;">NA</td>
			<td style="width:576px;">Email: Celina Juliano at celina.juliano@yale.edu or Hiroshi Shimizu bubuchin2006@yahoo.co.jp</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">High Speed Maxi Kit</td>
			<td style="width:112px;">Qiagen</td>
			<td align="right" style="width:119px;">12662</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">100 x 15 mm Petri Dishes</td>
			<td style="width:112px;">BD Falcon</td>
			<td align="right" style="width:119px;">351029</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">75 x 50 mm Glass Microscope Slide</td>
			<td style="width:112px;">Sigma</td>
			<td>CLS294775X50</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Microinjection Fish Mold</td>
			<td style="width:112px;">IBI Scientific</td>
			<td style="width:119px;">FM-600</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Borosilicate Glass with Filament</td>
			<td style="width:112px;">Sutter Instrument</td>
			<td style="width:119px;">BF100-50-10</td>
			<td>O.D.: 1.0 mm, I.D.: 0.50 mm, 10 cm length</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Flaming/Brown Micropipette Puller</td>
			<td style="width:112px;">Sutter Instrument</td>
			<td style="width:119px;">P-97</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Phenol Red</td>
			<td style="width:112px;">Sigma</td>
			<td style="width:119px;">P3532</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Jewelers Forceps, Durmont #5</td>
			<td style="width:112px;">Sigma</td>
			<td>F6521</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Scalpel Blade #15</td>
			<td style="width:112px;">Fisher</td>
			<td style="width:119px;">50-822-421</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Mineral oil</td>
			<td style="width:112px;">Sigma</td>
			<td style="width:119px;">M8410-500ML</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Microinjector</td>
			<td style="width:112px;">Narishige</td>
			<td style="width:119px;">IM-9B</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Magnetic Stand</td>
			<td style="width:112px;">Narishige</td>
			<td style="width:119px;">GJ-1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Iron Plate</td>
			<td style="width:112px;">Narishige</td>
			<td style="width:119px;">IP</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Joystick Micromanipulator</td>
			<td style="width:112px;">Narishige</td>
			<td style="width:119px;">MN-151</td>
			<td></td>
		</tr>
	</tbody>
</table>

generation of transgenic hydra by embryo microinjection

As a member of the phylum Cnidaria, the sister group to all bilaterians, Hydra can shed light on fundamental biological processes shared among multicellular animals. Hydra is used as a model for the study of regeneration, pattern formation, and stem cells. However, research efforts have been hampered by lack of a reliable method for gene perturbations to study molecular function. The development of transgenic methods has revitalized the study of Hydra biology1. Transgenic Hydra allow for the tracking of live cells, sorting to yield pure cell populations for biochemical analysis, manipulation of gene function by knockdown and over-expression, and analysis of promoter function. Plasmid DNA injected into early stage embryos randomly integrates into the genome early in development. This results in hatchlings that express transgenes in patches of tissue in one or more of the three lineages (ectodermal epithelial, endodermal epithelial, or interstitial). The success rate of obtaining a hatchling with transgenic tissue is between 10% and 20%. Asexual propagation of the transgenic hatchling is used to establish a uniformly transgenic line in a particular lineage. Generating transgenic Hydra is surprisingly simple and robust, and here we describe a protocol that can be easily implemented at low cost.

Estabelecer linhas de Hydra transgênicos Alimentar filhotes transgênicas a cada 2-3 dias com náuplios de Artemia. Os filhotes, por vezes, não comer por um ou dois dias após a eclosão. Alguns novos filhotes nunca vai comer, e, portanto, não vai sobreviver. Se o filhote é transgénicos quer na ectodérmica (Figura 1A) ou o tecido epitelial endodérmica, permitir que o animal a germinar e recolher as gemas que têm a maioria dos tecidos transgénicos <str...

Watch this Scientific Journal Video about Generation of Transgenic Hydra by Embryo Microinjection at JoVE.com

Generation of Transgenic Hydra by Embryo Microinjection

Stably transgenic Hydra are made by microinjection of plasmid DNA into embryos followed by random genomic integration and asexual propagation to establish a uniform line. Transgenic Hydra are used to track cell movements, overexpress genes, study promoter function, or knock down gene expression using RNAi.

Geração de Transgênicos<em&gt; Hydra</em&gt; Por microinjeção de embriões

As a member of the phylum Cnidaria, the sister group to all bilaterians, Hydra can shed light on fundamental biological processes shared among ...

generation-of-transgenic-hydra-by-embryo-microinjection

Research

JoVE Journal

Biology

Generation of Transgenic Hydra by Embryo Microinjection

13.9K visualizações.  Yale University School of Medicine. Stably transgenic Hydra are made by microinjection of plasmid DNA into embryos followed by random genomic integration and asexual propagation to establish a uniform line. Transgenic Hydra are used to track cell movements, overexpress genes, study promoter function, or knock down gene expression using RNAi. 

Vídeo: Generation of Transgenic Hydra by Embryo Microinjection

Microinjection of A. aegypti Embryos to Obtain Transgenic Mosquitoes

In this video, Nijole Jasinskiene demonstrates the methodology employed to generate transgenic Aedes aegypti mosquitoes, which are vectors for dengue fever.  The techniques for correctly preparing microinjection needles, dessicating embryos, and performing microinjection are demonstrated.

In this video, Nijole Jasinskiene demonstrates the methodology employed to generate transgenic Aedes aegypti mosquitoes, which are vectors for dengue fever. The techniques for correctly preparing microinjection needles, dessicating embryos, and performing microinjection are demonstrated.

Microinjeção de embriões A. aegypti obter mosquitos transgênicos

In this video, Nijole Jasinskiene demonstrates the methodology employed to generate transgenic Aedes aegypti mosquitoes, which are vectors for dengue ...

Biologia

Generation of Stable Transgenic C. elegans Using Microinjection

Transgenic Caenorhabditis elegans can be readily created via microinjection of a DNA plasmid solution into the gonad 1. The plasmid DNA rearranges to form extrachromosomal concatamers that are stably inherited, though not with the same efficiency as actual chromosomes 2. A gene of interest is co-injected with an obvious phenotypic marker, such as rol-6 or GFP, to allow selection of transgenic animals under a dissecting microscope. The exogenous gene may be expressed from its native promoter for cellular localization studies. Alternatively, the transgene can be driven by a different tissue-specific promoter to assess the role of the gene product in that particular cell or tissue. This technique efficiently drives gene expression in all tissues of C. elegans except for the germline or early embryo 3. Creation of transgenic animals is widely utilized for a range of experimental paradigms. This video demonstrates the microinjection procedure to generate transgenic worms. Furthermore, selection and maintenance of stable transgenic C. elegans lines is described.

This video demonstrates the technique of microinjection into the gonad of C. elegans to create transgenic animals.

Geração de transgênicos Estável C. elegans Usando microinjeção

Transgenic Caenorhabditis elegans can be readily created via microinjection of a DNA plasmid solution into the gonad 1.  The plasmid DNA rearranges to ...

Microinjection Techniques for Studying Mitosis in the Drosophila melanogaster Syncytial Embryo

This protocol describes the use of the Drosophila melanogaster syncytial embryo for studying mitosis1. Drosophila has useful genetics with a sequenced genome, and it can be easily maintained and manipulated. Many mitotic mutants exist, and transgenic flies expressing functional fluorescently (e.g. GFP) - tagged mitotic proteins have been and are being generated. Targeted gene expression is possible using the GAL4/UAS system2. 

The Drosophila early embryo carries out multiple mitoses very rapidly (cell cycle duration, &asymp;10 min). It is well suited for imaging mitosis, because during cycles 10-13, nuclei divide rapidly and synchronously without intervening cytokinesis at the surface of the embryo in a single monolayer just underneath the cortex. These rapidly dividing nuclei probably use the same mitotic machinery as other cells, but they are optimized for speed; the checkpoint is generally believed to not be stringent, allowing the study of mitotic proteins whose absence would cause cell cycle arrest in cells with a strong checkpoint. Embryos expressing GFP labeled proteins or microinjected with fluorescently labeled proteins can be easily imaged to follow live dynamics (Fig. 1). In addition, embryos can be microinjected with function-blocking antibodies or inhibitors of specific proteins to study the effect of the loss or perturbation of their function3. These reagents can diffuse throughout the embryo, reaching many spindles to produce a gradient of concentration of inhibitor, which in turn results in a gradient of defects comparable to an allelic series of mutants. Ideally, if the target protein is fluorescently labeled, the gradient of inhibition can be directly visualized4. It is assumed that the strongest phenotype is comparable to the null phenotype, although it is hard to formally exclude the possibility that the antibodies may have dominant effects in rare instances, so rigorous controls and cautious interpretation must be applied. Further away from the injection site, protein function is only partially lost allowing other functions of the target protein to become evident.

Microinjection Techniques for Studying Mitosis in the Drosophila melanogaster Syncytial Embryo

This protocol describes the use of microinjection and high resolution imaging in the Drosophila melanogaster syncytial embryo to study mitosis.

Técnicas de microinjeção para estudar na Mitose Drosophila melanogaster Embrião Sincicial

This protocol describes the use of the Drosophila melanogaster syncytial embryo  for studying mitosis1.  Drosophila has useful genetics with a sequenced ...

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.

Produção de transgênicos Xenopus laevis Por Restrição Integração Mediada por Enzima e Transplante Nuclear

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 ...

Generation of Transgenic C. elegans by Biolistic Transformation

The number of laboratories using the free living nematode C. elegans is rapidly growing. The popularity of this biological model is attributed to a rapid generation time and short life span, easy and inexpensive maintenance, fully sequenced genome, and array of RNAi resources and mutant animals. Additionally, analysis of the C. elegans genome revealed a great similarity between worms and higher vertebrates, which suggests that research in worms could be an important adjunct to studies performed in whole mice or cultured cells. A powerful and important part of worm research is the ability to use transgenic animals to study gene localization and function. Transgenic animals can be created either via microinjection of the worm germline or through the use of biolistic bombardment. Bombardment is a newer technique and is less familiar to a number of labs. Here we describe a simple protocol to generate transgenic worms by biolistic bombardment with gold particles using the Bio-Rad PDS-1000 system. Compared with DNA microinjection into hermaphrodite germline, this protocol has the advantage of not requiring special skills from the operator with regards to identifying worm anatomy or performing microinjection. Further multiple transgenic lines are usually obtained from a single bombardment. Also in contrast to microinjection, biolistic bombardment produces transgenic animals with both extrachromosomal arrays and integrated transgenes. The ability to obtain integrated transgenic lines can avoid the use of mutagenic protocols to integrate foreign DNA. In conclusion, biolistic bombardment can be an attractive method for the generation of transgenic animals, especially for investigators not interested in investing the time and effort needed to become skilled at microinjection.

Generation of Transgenic C. elegans by Biolistic Transformation

Transgenic worms are commonly used in C. elegans research. Described is a simple, yet effective, protocol to introduce transgenes into worms using biolistic bombardment with DNA-coated gold particles. The effort involved and results of bombardment compare favorably with microinjection for the generation of transgenic animals.

Geração de transgênicos C. elegans Por biobalística Transformação

The number of laboratories using the free living nematode C. elegans is rapidly growing. The popularity of this biological model is attributed to a rapid ...

Analysis of mRNA Nuclear Export Kinetics in Mammalian Cells by Microinjection

In eukaryotes, messenger RNA (mRNA) is transcribed in the nucleus and must be exported into the cytoplasm to access the translation machinery. Although the nuclear export of mRNA has been studied extensively in Xenopus oocytes1 and genetically tractable organisms such as yeast2 and the Drosophila derived S2 cell line3, few studies had been conducted in mammalian cells. Furthermore the kinetics of mRNA export in mammalian somatic cells could only be inferred indirectly4,5. In order to measure the nuclear export kinetics of mRNA in mammalian tissue culture cells, we have developed an assay that employs the power of microinjection coupled with fluorescent in situ hybridization (FISH). These assays have been used to demonstrate that in mammalian cells, the majority of mRNAs are exported in a splicing dependent manner6,7, or in manner that requires specific RNA sequences such as the signal sequence coding region (SSCR) 6. In this assay, cells are microinjected with either in vitro synthesized mRNA or plasmid DNA containing the gene of interest. The microinjected cells are incubated for various time points then fixed and the sub-cellular localization of RNA is assessed using FISH. In contrast to transfection, where transcription occurs several hours after the addition of nucleic acids, microinjection of DNA or mRNA allows for rapid expression and allows for the generation of precise kinetic data.

Here we describe an assay that employs the power of microinjection coupled with fluorescent in situ hybridization in order to accurately measure the nuclear export kinetics of mRNA in mammalian somatic cells.

Análise de Cinética mRNA Nuclear Exportação em células de mamíferos por microinjeção

In eukaryotes, messenger RNA (mRNA) is transcribed in the nucleus and must be exported into the cytoplasm to access the translation machinery. Although ...

Analyzing the Function of Small GTPases by Microinjection of Plasmids into Polarized Epithelial Cells

Epithelial cells polarize their plasma membrane into biochemically and functionally distinct apical and basolateral domains where the apical domain faces the 'free' surfaces and the basolateral membrane is in contact with the substrate and neighboring cells. Both membrane domains are separated by tight junctions, which form a diffusion barrier. Apical-basolateral polarization can be recapitulated successfully in culture when epithelial cells such as Madin-Darby Canine Kidney (MDCK) cells are seeded at high density on polycarbonate filters and cultured for several days 1 2. Establishment and maintenance of cell polarity is regulated by an array of small GTPases of the Ras superfamily such as RalA, Cdc42, Rab8, Rab10 and Rab13 3 4 5 6 7. Like all GTPases these proteins cycle between an inactive GDP-bound state and an active GTP-bound state. Specific mutations in the nucleotide binding regions interfere with this cycling 8. For example, Rab13T22N is permanently locked in the GDP-form and thus dubbed 'dominant negative', whereas Rab13Q67L can no longer hydrolyze GTP and is thus locked in a 'dominant active' state 7. To analyze their function in cells both dominant negative and dominant active alleles of GTPases are typically expressed at high levels to interfere with the function of the endogenous proteins 9. An elegant way to achieve high levels of overexpression in a short amount of time is to introduce the plasmids encoding the relevant proteins directly into the nuclei of polarized cells grown on filter supports using microinjection technique. This is often combined with the co-injection of reporter plasmids that encode plasma membrane receptors that are specifically sorted to the apical or basolateral domain. A cargo frequently used to analyze cargo sorting to the basolateral domain is a temperature sensitive allele of the vesicular stomatitis virus glycoprotein (VSVGts045) 10. This protein cannot fold properly at 39&deg;C and will thus be retained in the endoplasmic reticulum (ER) while the regulatory protein of interest is assembled in the cytosol. A shift to 31&deg;C will then allow VSVGts045 to fold properly, leave the ER and travel to the plasma membrane 11. This chase is typically performed in the presence of cycloheximide to prevent further protein synthesis leading to cleaner results. Here we describe in detail the procedure of microinjecting plasmids into polarized cells and subsequent incubations including temperature shifts that allow a comprehensive analysis of regulatory proteins involved in basolateral sorting.

This article details the procedures involved in overexpression and analysis of small GTPases in polarized epithelial cells using microinjection technique.

Analisando a função de GTPases Pequenas pela microinjeção de Plasmids em Polarized Células Epiteliais

Epithelial cells polarize their plasma membrane into biochemically and functionally distinct apical and basolateral domains where the apical domain faces ...

Activation of Apoptosis by Cytoplasmic Microinjection of Cytochrome c

Apoptosis, or programmed cell death, is a conserved and highly regulated pathway by which cells die1. Apoptosis can be triggered when cells encounter a wide range of cytotoxic stresses. These insults initiate signaling cascades that ultimately cause the release of cytochrome c from the mitochondrial intermembrane space to the cytoplasm2. The release of cytochrome c from mitochondria is a key event that triggers the rapid activation of caspases, the key cellular proteases which ultimately execute cell death3-4.
The pathway of apoptosis is regulated at points upstream and downstream of cytochrome c release from mitochondria5. In order to study the post-mitochondrial regulation of caspase activation, many investigators have turned to direct cytoplasmic microinjection of holocytochrome c (heme-attached) protein into cells6-9. Cytochrome c is normally localized to the mitochondria where attachment of a heme group is necessary to enable it to activate apoptosis10-11. Therefore, to directly activate caspases, it is necessary to inject the holocytochrome c protein instead of its cDNA, because while the expression of cytochrome c from cDNA constructs will result in mitochondrial targeting and heme attachment, it will be sequestered from cytosolic caspases. Thus, the direct cytosolic microinjection of purified heme-attached cytochrome c protein is a useful tool to mimic mitochondrial cytochrome c release and apoptosis without the use of toxic insults which cause cellular and mitochondrial damage.
In this article, we describe a method for the microinjection of cytochrome c protein into cells, using mouse embryonic fibroblasts (MEFs) and primary sympathetic neurons as examples. While this protocol focuses on the injection of cytochrome c for investigations of apoptosis, the techniques shown here can also be easily adapted for microinjection of other proteins of interest.

Activation of Apoptosis by Cytoplasmic Microinjection of Cytochrome c

In this protocol, we describe the direct cytoplasmic microinjection of cytochrome c protein into fibroblasts and primary sympathetic neurons. This technique allows for the introduction of cytochrome c protein into the cytoplasm of cells and mimics the release of cytochrome c from mitochondria, which occurs during apoptosis.

Ativação da apoptose por microinjeção citoplasmática de citocromo C</em

Apoptosis, or programmed cell death, is a conserved and highly regulated pathway by which cells die1.  Apoptosis can be triggered when cells encounter a ...

Generation of Myospheres From hESCs by Epigenetic Reprogramming

Generation of a homogeneous and abundant population of skeletal muscle cells from human embryonic stem cells (hESCs) is a requirement for cell-based therapies and for a "disease in a dish" model of human neuromuscular diseases. Major hurdles, such as low abundance and heterogeneity of the population of interest, as well as a lack of protocols for the formation of three-dimensional contractile structures, have limited the applications of stem cells for neuromuscular disorders. We have designed a protocol that overcomes these limits by ectopic introduction of defined factors in hESCs - the muscle determination factor MyoD and SWI/SNF chromatin remodeling complex component BAF60C - that are able to reprogram hESCs into skeletal muscle cells. Here we describe the protocol established to generate hESC-derived myoblasts and promote their clustering into tridimensional miniaturized structures (myospheres) that functionally mimic miniaturized skeletal muscles7.

Here, we describe a protocol based on epigenetic reprogramming of human embryonic stem cells (hESCs) toward generating a homogeneous population of skeletal muscle progenitors that under permissive culture conditions form three-dimensional clusters of contractile myofibers (myospheres), which recapitulate biological features of human skeletal muscles.

Geração de Myospheres De hESCs por epigenética Reprogramação

Generation of a homogeneous and abundant population of skeletal muscle cells from human embryonic stem cells (hESCs) is a requirement for cell-based ...

Culturing Caenorhabditis elegans in Axenic Liquid Media and Creation of Transgenic Worms by Microparticle Bombardment

In this protocol, we present the required materials, and the procedure for making modified&#160;C. elegans&#160;Habituation and Reproduction media (mCeHR). Additionally, the steps for exposing and acclimatizing C. elegans grown on E. coli to axenic liquid media are described. Finally, downstream experiments that utilize axenic C. elegans illustrate the benefits of this procedure. The ability to analyze and determine C. elegans&#160;nutrient requirement was illustrated by growing N2 wild type worms in axenic liquid media with varying heme concentrations. This procedure can be replicated with other nutrients to determine the optimal concentration for worm growth and development or, to determine the toxicological effects of drug treatments. The effects of varied heme concentrations on the growth of wild type worms were determined through qualitative microscopic observation and by quantitating the number of worms that grew in each heme concentration. In addition, the effect of varied nutrient concentrations can be assayed by utilizing worms that express fluorescent sensors that respond to changes in the nutrient of interest. Furthermore, a large number of worms were easily produced for the generation of transgenic C. elegans using microparticle bombardment.

Culturing Caenorhabditis elegans in Axenic Liquid Media and Creation of Transgenic Worms by Microparticle Bombardment

C. elegans is usually grown on solid agar plates or in liquid cultures seeded with E. coli. To prevent bacterial byproducts from confounding toxicological and nutritional studies, we utilized an axenic liquid medium, CeHR, to grow and synchronize a large number of worms for a range of downstream applications.