Agradecemos a membros de nossos laboratórios para discussões frutíferas e assistência técnica. Esta apresentação de vídeo foi apoiado pelo Reitor de Pesquisa e do Departamento de Patobiologia Veterinária, Centro de Ciências da Saúde Veterinária, Oklahoma State University. A pesquisa foi financiada pelo Ministério de Ciencia e Innovación, Espanha (projeto BFU2008-01244/BMC), o projeto CSIC intramural PA1002451 de JF, o Walter R. Sitlington cadeira dotada de Pesquisa Animal Food para KMK, 2009 CVHS RAC concessão, EOAs animais Fundos de Saúde e USDA, National Research Grant Initiative Competitiva, n º 2007-04613.

1. Geração de dsRNA. <ol><li> Sintetizar primers contendo seqüências de promotor T7 para transcrição in vitro ea síntese de dsRNA (por exemplo, para Dermacentor variabilis subolesin usar primers D8AAT75: 5&#39;-TAATACGACTCACTATAGGGTACTGACTGGGATCCCCTGCACAGT-3 &#39;e D8DVT73: 5&#39;-TAATACGACTCACTATAGGGTACTCGAGCTTGGTGGAAAGGACG-3&#39;). </li><li> Amplificar gene-alvo por RT-PCR utilizando 10 pmol de cada primer oligonucleotídeo e ng 1-10 de RNA total de carrapatos. </li><li> Purificar o produto da PCR. </li><li> Sintetizar dsRNA com 8 mL do produto da PCR purificada. </li><li> Quantificar dsRNA por espectrometria. </li></ol> 2. Injeção de Carrapatos com dsRNA. 2.1. Preparação de carrapatos injectável. <ol><li> Primeiro, lave a carrapatos em uma série de soluções, agitando-os em cada solução em um tubo de centrífuga de 50 mL descartáveis, decantação a solução através de uma tela fina malha de arame sobre a parte superior do tubo para manter os carrapatos. A seqüência das soluções para os carrapatos de lavagem é a água da torneira, peróxido de hidrogênio 3%, duas lavagens de água destilada, o etanol 70% e duas lavagens mais com água destilada. </li><li> Blot-seque a carrapatos em toalhas de papel. </li><li> Contar os carrapatos em grupos de 20 a 50, dependendo do experimento, coloque os carrapatos de cada grupo em um copo de plástico 1,25 onças com uma tampa bem ajustada e etiqueta com o número do grupo experimental. </li></ol> 2.2. Tick ​​equipe de injeção. A equipe de RNAi consiste em três pessoas: (1) uma pessoa que posições cada instante em fita adesiva dupla afixada a uma folha de cera dental vermelho, (2) uma pessoa que injeta os carrapatos e (3) uma pessoa que monitora os carrapatos após injeção, respira de CO 2 na carrapatos para ativá-las e conta os carrapatos que vivem em copos marcados com o número do grupo experimental. Todos os membros da equipe devem usar luvas descartáveis. 2.3. Colocação de carrapatos injectável. <ol><li> Captura de um carrapato com pinças Dumont fina e colocá-lo lado ventral em fita adesiva dupla aposta num 3 &quot;x 6&quot; folha de cera dental vermelho. Os carrapatos estão intimamente posicionados juntos em grupos de 5 carrapatos. </li><li> Coloque uma pequena tira de fita adesiva sobre o aparelho bucal de todos os cinco carrapatos, a fim de diminuir as deles, mas deixando a maior parte do corpo exposto para que o processo de injeção pode ser observado pelo carrapato injetor (Figura 1). </li></ol> 2.4. Injeção de carrapatos. <ol><li> Os carrapatos serão injetados no quadrante inferior direito da superfície ventral do exoesqueleto. </li><li> Primeiro, faça um furo no exoesqueleto usando uma seringa de insulina Monoject equipado com um ½ &quot;, agulha de calibre 29 (Figura 2a). </li><li> Injetar carrapatos imediatamente com 0,2-0,5 mL de solução de dsRNA (5 x 10 10 - 5 x 10 11 moléculas por mL), utilizando uma custom-made seringa Hamilton com uma polegada de 1, 33 agulha com um ponto de 45 ° chanfrado (Figura 2b) . A agulha deve ser colocada bem na cavidade carrapato para assegurar a colocação e retenção do dsRNA. Algum fluido é provável que escapar do local da injeção (Figura 2c). Cuidados devem ser tomados para não mais de injetar os carrapatos, o que causaria perda de hemolinfa e pode causar a morte do carrapato. </li><li> Limpe a seringa Hamilton depois de completar as injeções em cada grupo experimental. antes de usar para outro grupo experimental. Encha a seringa primeira de um copo contendo peróxido de hidrogênio 3% e, em seguida, expelir em um recipiente de resíduos, e repita 15 vezes. Encha a seringa de um copo contendo água estéril e, em seguida, expelir em um recipiente de resíduos, e repita 15 vezes. Tome cuidado para não dobrar o êmbolo da seringa de Hamilton, porque, se dobrado, o êmbolo não irá mover-se suavemente e responder ao toque suave necessária para injeção de carrapatos. </li></ol> 2.5. Tratamento de carrapatos após a injeção. <ol><li> Pegar o carrapato injetado imediatamente a partir da fita adesiva dupla com a pinça fina e colocá-lo em um recipiente de recuperação de plástico (cerca de 6 &quot;x 6&quot; e cercado com fita adesiva para evitar o escape dos carrapatos). Os carrapatos serão brevemente inativos após a injeção, mas deverá em breve começar a engatinhar ao redor do prato. </li><li> Respiração CO 2 para os carrapatos imediatamente após colocá-los no recipiente de recuperação para ajudar a ativar os carrapatos. Uma vez que os carrapatos estão rastejando e ativa, a ferida vai curar injeção rapidamente e eles provavelmente irão sobreviver. </li><li> Contar os ticks de acordo com o número em cada grupo experimental e os coloque em um copo de plástico rotulados com uma tampa bem equipado. Carrapatos substituição deve ser injetado para substituir qualquer que qualquer morreu antes de injetar o próximo grupo experimental. </li></ol> 2.6. Tick ​​exploração. <ol><li> Coloque os carrapatos em uma câmara de umidade (12h de luz: 12 hr fotoperíodo escuro, a 22-25 ° C e 95% em relação humidity) e segure por um dia. </li><li> Carrapatos lugar no carrapato-alimentação células, uma por grupo experimental, colada a uma ovelha e permitir-lhes para se alimentar com um número igual de uninjected carrapatos masculina ou feminina (o que o sexo não foi injetado). Carrapatos fêmeas que se alimentam de reposição, aqueles que são retirados da ovelha após 10 dias de alimentação, ou quando as fêmeas controle têm deixado o anfitrião são coletados e pesados. </li><li> Coloque os carrapatos em caixas de cartão, e segure a câmara de umidade até a conclusão de oviposição. Avaliar oviposição pela ponderação das massa de ovos produzidos por todos os carrapatos no grupo. </li></ol> 2.7. Análise do fenótipo tick após RNAi. <ol><li> Avaliar carrapato fenótipo após a alimentação, determinando o número de carrapatos que sobreviveram, peso carrapato, oviposição e fertilidade dos ovos. No entanto, outras análises podem ser realizadas, dependendo do gene-alvo e objetivos do estudo. </li></ol> 3. Análise para confirmar o silenciamento do gene por RT-PCR. <ol><li> Dissecar as glândulas salivares e tripas de carrapatos individuais de grupos de controle de injeção e dsRNA injetado após a alimentação. </li><li> Extrato de RNA total de amostras de tecido individual. </li><li> Analisar as transcrições gene alvo nos tecidos individuais por real-time RT-PCR e normalizar os níveis de RNA contra o 16S rRNA tick usando o método genNorm (método ddCT implementada pelo Bio-Rad iQ5 Standard Edition, versão 2.0). </li><li> Executar curvas de dissociação no final da reação para garantir que apenas um amplicon é formada e que a desnaturar amplicons consistentemente na faixa de temperatura mesmo para cada amostra. </li><li> Comparar os níveis de mRNA (valores normalizados Ct) entre o controle com injeção e dsRNA injetado carrapatos usando o Student `s t-test (P = 0,05). </li></ol> 4. Resultados representativos: O protocolo aqui descrito tem sido utilizado em nosso laboratório para RNAi em muitas diferentes espécies de carrapatos ixodídeos (Tabela 1). A quantidade de dsRNA injetado no carrapatos varia com o tamanho do carrapato; espécies maiores carrapato pode acomodar um grande volume. Carrapatos controle negativo deve ser injectado com um dsRNA não relacionados. DsRNAs diversas, tais como subolesin 14-19,22-25,27-32,34 e beta-actina 20,21 pode ser usado como controle positivo. Note que é importante lavar a seringa entre os tratamentos para evitar soluções de mistura dsRNA. Se o protocolo for feito corretamente, menos de 5% de mortalidade deve ser obtido a partir do procedimento de injeção após 24 horas. Um fenótipo típico após knockdown do gene em carrapatos é mostrado na Figura 3, com um painel de carrapatos injetados com piscinas de dsRNA, a fim de tela para assinalar antígenos protetores. <table border="1"><tbody><tr><td> Tick ​​espécies </td><td> dsRNA injetado </td><td> Referências </td></tr><tr><td> Scapularis Ixodes </td><td> biblioteca de cDNA, subolesin, actina, nucleotidase, NF-kB, akirin </td><td> 21, 22, 29, 30 </td></tr><tr><td> Dermacentor variabilis </td><td> subolesin, GST, ubiquitina, vATPase, selenoproteínas M e W2a, tronco hematopoiéticas / progenitoras proteína-like, actina subunidade 26S Proteassoma, ferritin1, varisin, akirin </td><td> 15, 19, 22, 24, 26, 30-32 </td></tr><tr><td> Dermacentor marginatus </td><td> subolesin </td><td> 22 </td></tr><tr><td> Amblyomma americanum </td><td> biblioteca de cDNA, subolesin, akirin </td><td> 17, 22, 30 </td></tr><tr><td> Amblyomma hebraeum </td><td> subolesin, voraxin </td><td> 28 </td></tr><tr><td> Rhipicephalus sanguineus </td><td> Rs86, subolesin </td><td> 22, 23 </td></tr><tr><td> Rhipicephalus microplus </td><td> GST, ubiquitina, selenoproteína, Bm86, Bm91, subolesin, GI, GIII, EF1a, flagelliform proteína de seda, von Willebrand fator </td><td> 16, 18, 25, 27 </td></tr><tr><td> Annulatus Rhipicephalus </td><td> ubiquitina, subolesin, EF1a, GIII </td><td> 16 </td></tr></tbody></table> Tabela 1. Tick espécies em que o protocolo de RNAi tem sido utilizado. <img src="/files/ftp_upload/2474/2474fig1.jpg" alt="Figura 1" /> Figura 1. Colocação de carrapatos, o lado ventral para cima, sobre fita adesiva dupla adere a uma folha de cera dental vermelho. Os carrapatos são colocados em grupos de 5, após o qual uma pequena tira de fita adesiva é colocada sobre o aparelho bucal, a fim de proteger ainda mais os carrapatos, permitindo que o injector para observar o corpo do carrapato durante a injeção. <img src="/files/ftp_upload/2474/2474fig2.jpg" alt="Figura 2" /> Figura 2. O procedimento de injeção inclui (a) perfuração no quadrante inferior direito do exoesqueleto do carrapato com uma insulina de syringe com uma agulha calibre 29, a fim de criar um local da injeção, (b) a injeção imediata do dsRNA neste site, utilizando uma seringa Hamilton com uma agulha de calibre 33, que (c) muito provavelmente vai resultar em algum vazamento de hemolinfa carrapato / fluidos. <img src="/files/ftp_upload/2474/2474fig3.jpg" alt="Figura 3" /> Figura 3. Um painel de carrapato seis grupos em que RNAi foi utilizado para triagem de antígenos carrapato Amblyomma americanum protetora em. As mudanças fenotípicas em carrapatos pode ser visto quando comparado com o positivo subolesin RNAi controle eo controle dsRNA negativas não relacionadas. Neste experimento o efeito do RNAi na mortalidade carrapato, pesos e oviposição de cada grupo foram analisados ​​estatisticamente.

<ol>
	<li>de la Fuente, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Overview:+Ticks+as+vectors+of+pathogens+that+cause+disease+in+humans+and+animals.">Overview: Ticks as vectors of pathogens that cause disease in humans and animals.</a> Front. Biosci. 13, 6938-6946 (2008).</li><li>Peter, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=mosquito+control-Lessons+from+the+past,+solutions+for+the+future.">mosquito control-Lessons from the past, solutions for the future.</a> Vet. Parasitol. 132, 205-215 (2005).</li><li>Barker, S. C., Murrell, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Systematics+and+evolution+of+ticks+with+a+list+of+valid+genus+and+species+names.">Systematics and evolution of ticks with a list of valid genus and species names.</a> Parasitol. 129, S15-S36 (2004).</li><li>Willadsen, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tick+control:+Thoughts+on+a+research+agenda.">Tick control: Thoughts on a research agenda.</a> Vet. Parasitol. 138, 161-168 (2006).</li><li>de la Fuente, J., Kocan, K. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Strategies+for+development+of+vaccines+for+control+of+ixodid+tick+species.">Strategies for development of vaccines for control of ixodid tick species.</a> Parasite Immunol. 28, 275-283 (2006).</li><li>Fire, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Potent+and+specific+genetic+interference+by+double-stranded+RNA+in+Caenorhabditis+elegans.">Potent and specific genetic interference by double-stranded RNA in Caenorhabditis elegans.</a> Nature. 391, 806-811 (1998).</li><li>Cerutti, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=RNA+interference:+traveling+in+the+cell+and+gaining+functions.">RNA interference: traveling in the cell and gaining functions.</a> Trends Genet. 19, 39-46 (2003).</li><li>Kavi, H. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=RNA+silencing+in+Drosophila.">RNA silencing in Drosophila.</a> FEBS Lett. 579, 5940-5949 (2005).</li><li>Mello, C. C., Conte, D. J. r. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Revealing+the+world+of+RNA+interference.">Revealing the world of RNA interference.</a> Nature. 431, 338-342 (2004).</li><li>Zhou, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=RNA+interference+and+potential+applications.">RNA interference and potential applications.</a> Curr. Top. Med. Chem. 6, 901-911 (2006).</li><li>Ramakrishnan, V. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Application+of+RNA+interference+in+tick+salivary+gland+research.">Application of RNA interference in tick salivary gland research.</a> J. Biomol. Tech. 16, 297-305 (2005).</li><li>Aljamali, M. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=RNA+interference:+applicability+in+tick+research.">RNA interference: applicability in tick research.</a> Exp. Appl. Acarol. 28, 89-96 (2002).</li><li>Aljamali, M. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=RNA+interference+in+ticks:+a+study+using+histamine+binding+protein+dsRNA+in+the+female+tick+Amblyomma+americanum.">RNA interference in ticks: a study using histamine binding protein dsRNA in the female tick Amblyomma americanum.</a> Insect. Mol. Biol. 12, 299-305 (2003).</li><li>de la Fuente, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=RNA+interference+for+the+study+and+genetic+manipulation+of+ticks.">RNA interference for the study and genetic manipulation of ticks.</a> Trends Parasitol. 23, 427-433 (2007).</li><li>de la Fuente, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+genomic+studies+of+tick+cells+in+response+to+infection+with+the+cattle+pathogen,+Anaplasma+marginale.">Functional genomic studies of tick cells in response to infection with the cattle pathogen, Anaplasma marginale.</a> Genomics. 90, 712-722 (2007).</li><li>Almaz&#228;N, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+and+characterization+of+Rhipicephalus+(Boophilus)+microplus+candidate+protective+antigens+for+the+control+of+cattle+tick+infestations.">Identification and characterization of Rhipicephalus (Boophilus) microplus candidate protective antigens for the control of cattle tick infestations.</a> Parasitol. Res. 106, 471-479 (2010).</li><li>de la Fuente, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+protective+antigens+by+RNA+interference+for+control+of+the+lone+star+tick,+Amblyomma+americanum.">Identification of protective antigens by RNA interference for control of the lone star tick, Amblyomma americanum.</a> Vaccine. 28, 1786-1795 (2010).</li><li>Zivkovic, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+expression+of+genes+in+salivary+glands+of+male+Rhipicephalus+(Boophilus)+microplus+in+response+to+infection+with+Anaplasma+marginale.">Differential expression of genes in salivary glands of male Rhipicephalus (Boophilus) microplus in response to infection with Anaplasma marginale.</a> BMC Genomics. 11, 186-186 (2010).</li><li>de la Fuente, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reduction+of+tick+infections+with+Anaplasma+marginale+and+A.+phagocytophilum+by+targeting+the+tick+protective+antigen+subolesin.">Reduction of tick infections with Anaplasma marginale and A. phagocytophilum by targeting the tick protective antigen subolesin.</a> Parasitol. Res. 100, 85-91 (2006).</li><li>Narasimhan, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Disruption+of+Ixodes+scapularis+anticoagulation+by+using+RNA+interference.">Disruption of Ixodes scapularis anticoagulation by using RNA interference.</a> Proc. Natl. Acad. Sci U.S.A. 101, 1141-1146 (2004).</li><li>de la Fuente, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=RNA+interference+screening+in+ticks+for+identification+of+protective+antigens.">RNA interference screening in ticks for identification of protective antigens.</a> Parasitol. Res. 96, 137-141 (2005).</li><li>de la Fuente, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+tick+protective+antigen,+4D8,+is+a+conserved+protein+involved+in+modulation+of+tick+blood+ingestion+and+reproduction.">The tick protective antigen, 4D8, is a conserved protein involved in modulation of tick blood ingestion and reproduction.</a> Vaccine. 24, 4082-4095 (2006).</li><li>de la Fuente, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synergistic+effect+of+silencing+the+expression+of+tick+protective+antigens+4D8+and+Rs86+in+Rhipicephalus+sanguineus+by+RNA+interference.">Synergistic effect of silencing the expression of tick protective antigens 4D8 and Rs86 in Rhipicephalus sanguineus by RNA interference.</a> Parasitol. Res. 99, 108-113 (2006).</li><li>de la Fuente, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Autocidal+control+of+ticks+by+silencing+of+a+single+gene+by+RNA+interference.">Autocidal control of ticks by silencing of a single gene by RNA interference.</a> Biochem. Biophys. Res. Commun. 344, 332-338 (2006).</li><li>Nijhof, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bm86,+Bm91+and+subolesin,+in+the+silencing+of+the+tick+protective+antigens.">Bm86, Bm91 and subolesin, in the silencing of the tick protective antigens.</a> Int. J. Parasitol. 37, 653-662 (2007).</li><li>Kocan, K. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Silencing+of+the+defensin,+varisin,+in+male+Dermacentor+variabilis+by+RNA+interference+results+in+reduced+Anaplasma+marginale+infections.">Silencing of the defensin, varisin, in male Dermacentor variabilis by RNA interference results in reduced Anaplasma marginale infections.</a> Exp. Appl. Acarol. 46, 17-28 (2008).</li><li>de la Fuente, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evidence+of+the+role+of+tick+subolesin+in+gene+expression.">Evidence of the role of tick subolesin in gene expression.</a> BMC Genomics. 9, 372-372 (2008).</li><li>Smith, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+impact+of+RNA+interference+of+the+subolesin+and+voraxin+genes+in+male+Amblyomma+hebraeum+(Acari:+Ixodidae)+on+female+engorgement+and+oviposition.">The impact of RNA interference of the subolesin and voraxin genes in male Amblyomma hebraeum (Acari: Ixodidae) on female engorgement and oviposition.</a> Exp. Appl. Acarol. 47, 71-86 (2009).</li><li>Galindo, R. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tick+subolesin+is+an+ortholog+of+the+akirins+described+in+insects+and+vertebrates.">Tick subolesin is an ortholog of the akirins described in insects and vertebrates.</a> Dev. Comp. Immunol. 33, 612-617 (2009).</li><li>Canales, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Conservation+and+immunogenicity+of+the+mosquito+ortholog+of+the+tick+protective+antigen,+subolesin.">Conservation and immunogenicity of the mosquito ortholog of the tick protective antigen, subolesin.</a> Parasitol. Res. 105, 97-111 (2009).</li><li>Kocan, K. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Silencing+of+genes+involved+in+Anaplasma+marginale-tick+interactions+affects+the+pathogen+developmental+cycle+in+Dermacentor+variabilis.">Silencing of genes involved in Anaplasma marginale-tick interactions affects the pathogen developmental cycle in Dermacentor variabilis.</a> BMC Dev. Biol. 9, 42-42 (2009).</li><li>Zivkovic, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Subolesin+expression+in+response+to+pathogen+infection+in+ticks.">Subolesin expression in response to pathogen infection in ticks.</a> BMC Immunol. 11, 7-7 (2010).</li><li>Karim, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+genomics+tool:+gene+silencing+in+Ixodes+scapularis+eggs+and+nymphs+by+electroporated+dsRNA.">Functional genomics tool: gene silencing in Ixodes scapularis eggs and nymphs by electroporated dsRNA.</a> BMC Biotechnol. 10, 1-1 (2010).</li><li>Kocan, K. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transovarial+silencing+of+the+subolesin+gene+in+three-host+ixodid+tick+species+after+injection+of+replete+females+with+subolesin+dsRNA.">Transovarial silencing of the subolesin gene in three-host ixodid tick species after injection of replete females with subolesin dsRNA.</a> Parasitol. Res. 100, 1411-1415 (2007).</li><li>de la Fuente, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeting+the+tick-pathogen+interface+for+novel+control+strategies.">Targeting the tick-pathogen interface for novel control strategies.</a> Front. Biosci. 13, 6947-6956 (2008).</li><li>Kurscheid, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evidence+of+a+tick+RNAi+pathway+by+comparative+genomics+and+reverse+genetics+screen+of+targets+with+known+loss-of-function+phenotypes+in+Drosophila.">Evidence of a tick RNAi pathway by comparative genomics and reverse genetics screen of targets with known loss-of-function phenotypes in Drosophila.</a> BMC Mol. Biol. 10, 26-26 (2009).</li></ol>

Não há conflitos de interesse declarados.

Embora outros métodos têm sido descritos para RNAi em carrapatos 14, 33, a injeção de dsRNA aqui descrito é o mais utilizado em ambos os jejum (Tabela 1) e carrapatos alimentados 16,25,34. RNAi tem se mostrado uma ferramenta valiosa para o estudo da função dos genes carrapato, a caracterização da interface carrapato-patógeno e ao rastreio e caracterização de antígenos de carrapatos de proteção 14,35. Em particular, RNAi se tornou a ferramenta mais valiosa para análises funcionais em carrapatos 35. Metodologicamente, RNAi provavelmente evoluir para métodos mais eficientes que podem permitir knockdown do gene em um grande número de indivíduos. O mecanismo de dsRNA induzida por RNAi em carrapatos deve ser refinado para contribuir para uma melhor compreensão e utilização desta abordagem genética nesta espécie 35,36. A extensão de fora do alvo os efeitos da RNAi em carrapatos também é uma questão importante que precisa ser totalmente dirigida 14,27. Finalmente, RNAi provavelmente irá fornecer contribuições ao estudo abrangente da regulação de genes e carrapato biologia de sistemas e do carrapato-patógeno interface e pode ter um impacto sobre o desenvolvimento de vacinas para controlar a infestação de carrapatos e de transmissão de patógenos por carrapatos.

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">	
		
		<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>Access RT-PCR system</td>
<td>&nbsp;</td>
<td>Promega</td>
<td>A1250</td>
<td>&nbsp;</td>
<tr>
<td>Purelink PCR purification kit</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>K3100-02</td>
<td>&nbsp;</td>
<tr>
<td>Megascript RNAi kit</td>
<td>&nbsp;</td>
<td>Ambion</td>
<td>AM1626M</td>
<td>&nbsp;</td>
<tr>
<td>Red dental wax</td>
<td>&nbsp;</td>
<td>Electron Microscopy Sciences</td>
<td>72674</td>
<td>&nbsp;</td>
<tr>
<td>Plastic cups, 1.25 oz and lids</td>
<td>&nbsp;</td>
<td>Solo Cup Company, Urbana Ill.</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Fine forceps</td>
<td>&nbsp;</td>
<td>Electron Microscopy Sciences</td>
<td>Various</td>
<td>&nbsp;</td>
<tr>
<td>Insulin syringe</td>
<td>&nbsp;</td>
<td>Monoject</td>
<td>&nbsp;</td>
<td>Fitted with a &frac12;&#x201D;, 29 gauge needle</td>
</tr>
<tr>
<td>Hamilton syringe</td>
<td>&nbsp;</td>
<td>Hamilton</td>
<td>701SN,33/.375&#x201D;/45DGR</td>
<td>Custom made</td>
</tr>
<tr>
<td>TriReagent</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>93289</td>
<td>&nbsp;</td>
<tr>
<td>iScript One-Step RT-PCR Kit with SYBR Green</td>
<td>&nbsp;</td>
<td>Bio-Rad</td>
<td>170-8892</td>
<td>&nbsp;</td>
<tr>
<td>Real-time PCR detection system</td>
<td>&nbsp;</td>
<td>Bio-Rad</td>
<td>Several</td>
<td>Please refer to <a href="http://www.bio-rad.com/">http://www.bio-rad.com/</a></td>
</tr>		</tbody>
		</table>
		</div>

rna interference in ticks

Carrapatos são ectoparasitas hematófagos obrigatórios de animais selvagens e domésticos e seres humanos, e são considerados em todo o mundo segundo a mosquitos como vetores de doenças humanas 1 e os vetores mais importantes que afetam pecuária em todo o mundo 2. Carrapatos são classificados na subclasse Acari, Parasitiformes ordem, subordem Ixodida e são distribuídas em todo o mundo a partir do Ártico para as regiões tropical 3. Apesar dos esforços para controlar a infestação de carrapatos, estes ectoparasitas continuar a ser um problema sério para a saúde humana e animal 4,5. Interferência de RNA (RNAi) 6 é uma abordagem inversa à base de ácido nucléico genética que envolve a interrupção da expressão do gene, a fim de determinar a função do gene ou o seu efeito em uma via metabólica. Pequenos RNAs de interferência (siRNAs) são as moléculas efetoras da via RNAi que é iniciado pelo double-stranded RNA (dsRNA) e resulta em um potente seqüência específica de degradação de mRNAs citoplasmáticos contendo a mesma seqüência como o gatilho dsRNA 7-9. Pós-transcricional mecanismos de silenciamento de genes iniciado por dsRNA foram descobertas em todos os eucariotos estudados até agora, e RNAi foi rapidamente desenvolvido em uma variedade de organismos como uma ferramenta para estudos de genômica funcional e outras aplicações 10. RNAi tem se tornado a mais utilizada técnica de silenciamento de genes em carrapatos e outros organismos em que as abordagens alternativas para a manipulação genética não estão disponíveis ou são pouco confiáveis ​​5,11. A caracterização genética de carrapatos tem sido limitado até que a recente aplicação de RNAi 12,13. No pouco tempo que RNAi tem sido disponível, ele provou ser um instrumento valioso para estudar a função do gene carrapato, a caracterização da interface carrapato-patógeno e ao rastreio e caracterização de antígenos de carrapatos de proteção 14. Aqui, um método para RNAi através da injeção de dsRNA em carrapatos em jejum é descrito. É provável que o conhecimento adquirido a partir desta abordagem experimental contribuirá significativamente para a compreensão dos sistemas biológicos básicos e ao desenvolvimento de vacinas para controlar a infestação de carrapato e prevenir a transmissão de patógenos por carrapatos 15-19.

Watch this Scientific Journal Video about RNA Interference in Ticks at JoVE.com

RNA Interference in Ticks

Um método para a interferência de RNA (RNAi) pela injeção de dsRNA em carrapatos em jejum é descrito. RNAi é a mais utilizada técnica de silenciamento de genes em carrapatos onde o uso de outros métodos de manipulação genética tem sido limitado.

RNA de interferência em Carrapatos

Ticks are obligate hematophagous ectoparasites of wild and domestic animals and humans, and are considered to be second worldwide to mosquitoes as vectors ...

Research

JoVE Journal

Immunology and Infection

18.0K visualizações.  Oklahoma State University. Um método para a interferência de RNA (RNAi) pela injeção de dsRNA em carrapatos em jejum é descrito. RNAi é a mais utilizada técnica de silenciamento de genes em carrapatos onde o uso de outros métodos de manipulação genética tem sido limitado.

Vídeo: RNA Interference in Ticks

Development of Cell-type specific anti-HIV gp120 aptamers for siRNA delivery

The global epidemic of infection by HIV has created an urgent need for new classes of antiretroviral agents. The potent ability of small interfering (si)RNAs to inhibit the expression of complementary RNA transcripts is being exploited as a new class of therapeutics for a variety of diseases including HIV. Many previous reports have shown that novel RNAi-based anti-HIV/AIDS therapeutic strategies have considerable promise; however, a key obstacle to the successful therapeutic application and clinical translation of siRNAs is efficient delivery. Particularly, considering the safety and efficacy of RNAi-based therapeutics, it is highly desirable to develop a targeted intracellular siRNA delivery approach to specific cell populations or tissues. The HIV-1 gp120 protein, a glycoprotein envelope on the surface of HIV-1, plays an important role in viral entry into CD4 cells. The interaction of gp120 and CD4 that triggers HIV-1 entry and initiates cell fusion has been validated as a clinically relevant anti-viral strategy for drug discovery. 
Herein, we firstly discuss the selection and identification of 2'-F modified anti-HIV gp120 RNA aptamers. Using a conventional nitrocellulose filter SELEX method, several new aptamers with nanomolar affinity were isolated from a 50 random nt RNA library. In order to successfully obtain bound species with higher affinity, the selection stringency is carefully controlled by adjusting the conditions. The selected aptamers can specifically bind and be rapidly internalized into cells expressing the HIV-1 envelope protein. Additionally, the aptamers alone can neutralize HIV-1 infectivity. Based upon the best aptamer A-1, we also create a novel dual inhibitory function anti-gp120 aptamer-siRNA chimera in which both the aptamer and the siRNA portions have potent anti-HIV activities. Further, we utilize the gp120 aptamer-siRNA chimeras for cell-type specific delivery of the siRNA into HIV-1 infected cells. This dual function chimera shows considerable potential for combining various nucleic acid therapeutic agents (aptamer and siRNA) in suppressing HIV-1 infection, making the aptamer-siRNA chimeras attractive therapeutic candidates for patients failing highly active antiretroviral therapy (HAART).

Several 2&#x2019;-Fluoro RNA aptamers against HIV-1Ba-L gp120 with nanomole affinity are isolated from a RNA library by in vitro SELEX procedure. A new dual inhibitory function anti-gp120 aptamer-siRNA chimera is created and shows considerable promise for systemic anti-HIV therapy.

Desenvolvimento de células de tipo específico anti-HIV gp120 aptâmeros para entrega siRNA

The global epidemic of infection by HIV has created an urgent need for new classes of antiretroviral agents. The potent ability of small interfering ...

Imunologia e Infecção

Saliva, Salivary Gland, and Hemolymph Collection from Ixodes scapularis Ticks

Ticks are found worldwide and afflict humans with many tick-borne illnesses. Ticks are vectors for pathogens that cause Lyme disease and tick-borne relapsing fever (Borrelia spp.), Rocky Mountain Spotted fever (Rickettsia rickettsii), ehrlichiosis (Ehrlichia chaffeensis and E. equi), anaplasmosis (Anaplasma phagocytophilum), encephalitis (tick-borne encephalitis virus), babesiosis (Babesia spp.), Colorado tick fever (Coltivirus), and tularemia (Francisella tularensis) 1-8. To be properly transmitted into the host these infectious agents differentially regulate gene expression, interact with tick proteins, and migrate through the tick 3,9-13. For example, the Lyme disease agent, Borrelia burgdorferi, adapts through differential gene expression to the feast and famine stages of the tick's enzootic cycle 14,15. Furthermore, as an Ixodes tick consumes a bloodmeal Borrelia replicate and migrate from the midgut into the hemocoel, where they travel to the salivary glands and are transmitted into the host with the expelled saliva 9,16-19.
As a tick feeds the host typically responds with a strong hemostatic and innate immune response 11,13,20-22. Despite these host responses, I. scapularis can feed for several days because tick saliva contains proteins that are immunomodulatory, lytic agents, anticoagulants, and fibrinolysins to aid the tick feeding 3,11,20,21,23. The immunomodulatory activities possessed by tick saliva or salivary gland extract (SGE) facilitate transmission, proliferation, and dissemination of numerous tick-borne pathogens 3,20,24-27. To further understand how tick-borne infectious agents cause disease it is essential to dissect actively feeding ticks and collect tick saliva. This video protocol demonstrates dissection techniques for the collection of hemolymph and the removal of salivary glands from actively feeding I. scapularis nymphs after 48 and 72 hours post mouse placement. We also demonstrate saliva collection from an adult female I. scapularis tick.

Saliva, Salivary Gland, and Hemolymph Collection from Ixodes scapularis Ticks

The collection of infected tick hemolymph, salivary glands, and saliva is important to study how tick-borne pathogens cause disease. In this protocol we demonstrate how to collect hemolymph and salivary glands from feeding Ixodes scapularis nymphs. We also demonstrate saliva collection from female I. scapularis adults.

A saliva, glândula salivar, e Coleta de hemolinfa de carrapatos Ixodes scapularis

Ticks are found worldwide and afflict humans with many tick-borne illnesses. Ticks are vectors for pathogens that cause Lyme disease and tick-borne ...

Feeding of Ticks on Animals for Transmission and Xenodiagnosis in Lyme Disease Research

Transmission of the etiologic agent of Lyme disease, Borrelia burgdorferi, occurs by the attachment and blood feeding of Ixodes species ticks on mammalian hosts. In nature, this zoonotic bacterial pathogen may use a variety of reservoir hosts, but the white-footed mouse (Peromyscus leucopus) is the primary reservoir for larval and nymphal ticks in North America. Humans are incidental hosts most frequently infected with B. burgdorferi by the bite of ticks in the nymphal stage. B. burgdorferi adapts to its hosts throughout the enzootic cycle, so the ability to explore the functions of these spirochetes and their effects on mammalian hosts requires the use of tick feeding. In addition, the technique of xenodiagnosis (using the natural vector for detection and recovery of an infectious agent) has been useful in studies of cryptic infection. In order to obtain nymphal ticks that harbor B. burgdorferi, ticks are fed live spirochetes in culture through capillary tubes. Two animal models, mice and nonhuman primates, are most commonly used for Lyme disease studies involving tick feeding. We demonstrate the methods by which these ticks can be fed upon, and recovered from animals for either infection or xenodiagnosis.

Lyme disease is the most commonly-reported vector-borne disease in North America. The causative agent, Borrelia burgdorferi is a spirochete bacterium transmitted by Ixodid ticks. Transmission and detection of infection in animal models is optimized by the use of tick feeding, which we describe here.

Alimentação dos Carrapatos em Animais de Transmissão e Xenodiagnóstico em Lyme Disease Research

Transmission of the etiologic agent of Lyme disease, Borrelia burgdorferi, occurs by the  attachment and blood feeding of Ixodes species ticks on ...

Using RNA-interference to Investigate the Innate Immune Response in Mouse Macrophages

Macrophages are key phagocytic innate immune cells. When macrophages encounter a pathogen, they produce antimicrobial proteins and compounds to kill the pathogen, produce various cytokines and chemokines to recruit and stimulate other immune cells, and present antigens to stimulate the adaptive immune response. Thus, being able to efficiently manipulate macrophages with techniques such as RNA-interference (RNAi) is critical to our ability to investigate this important innate immune cell. However, macrophages can be technically challenging to transfect and can exhibit inefficient RNAi-induced gene knockdown. In this protocol, we describe methods to efficiently transfect two mouse macrophage cell lines (RAW264.7 and J774A.1) with siRNA using the Amaxa Nucleofector 96-well Shuttle System and describe procedures to maximize the effect of siRNA on gene knockdown. Moreover, the described methods are adapted to work in 96-well format, allowing for medium and high-throughput studies. To demonstrate the utility of this approach, we describe experiments that utilize RNAi to inhibit genes that regulate lipopolysaccharide (LPS)-induced cytokine production.

In this protocol, we describe methods to efficiently transfect murine macrophage cell lines with siRNAs using the Amaxa Nucleofector 96-well Shuttle System, stimulate the macrophages with lipopolysaccharide, and monitor the effects on inflammatory cytokine production.

Usando RNA-interferência para investigar a imunitário inatas de resposta em macrófagos

Macrophages are key phagocytic innate immune cells.  When macrophages encounter a pathogen, they produce antimicrobial proteins and compounds to kill the ...

Nucleocapsid Annealing-Mediated Electrophoresis (NAME) Assay Allows the Rapid Identification of HIV-1 Nucleocapsid Inhibitors

RNA or DNA folded in stable tridimensional folding are interesting targets in the development of antitumor or antiviral drugs. In the case of HIV-1, viral proteins involved in the regulation of the virus activity recognize several nucleic acids. The nucleocapsid protein NCp7 (NC) is a key protein regulating several processes during virus replication. NC is in fact a chaperone destabilizing the secondary structures of RNA and DNA and facilitating their annealing. The inactivation of NC is a new approach and an interesting target for anti-HIV therapy. The Nucleocapsid Annealing-Mediated Electrophoresis (NAME) assay was developed to identify molecules able to inhibit the melting and annealing of RNA and DNA folded in thermodynamically stable tridimensional conformations, such as hairpin structures of TAR and cTAR elements of HIV, by the nucleocapsid protein of HIV-1. The new assay employs either the recombinant or the synthetic protein, and oligonucleotides without the need of their previous labeling. The analysis of the results is achieved by standard polyacrylamide gel electrophoresis (PAGE) followed by conventional nucleic acid staining. The protocol reported in this work describes how to perform the NAME assay with the full-length protein or its truncated version lacking the basic N-terminal domain, both competent as nucleic acids chaperones, and how to assess the inhibition of NC chaperone activity by a threading intercalator. Moreover, NAME can be performed in two different modes, useful to obtain indications on the putative mechanism of action of the identified NC inhibitors.

Nucleocapsid Annealing-Mediated Electrophoresis NAME Assay Allows the Rapid Identification of HIV-1 Nucleocapsid Inhibitors

This protocol describes NAME, an assay that allows the rapid identification of molecules able to inhibit in vitro the chaperone activities of HIV-1 nucleocapsid protein.

Nucleocápside Annealing-Mediated Eletroforese (NAME) ensaio permite a identificação rápida de HIV-1 Nucleocápside Inibidores

RNA or DNA folded in stable tridimensional folding are interesting targets in the development of antitumor or antiviral drugs. In the case of HIV-1, viral ...

Applying an Inducible Expression System to Study Interference of Bacterial Virulence Factors with Intracellular Signaling

The technique presented here allows one to analyze at which step a target protein, or alternatively a small molecule, interacts with the components of a signaling pathway. The method is based, on the one hand, on the inducible expression of a specific protein to initiate a signaling event at a defined and predetermined step in the selected signaling cascade. Concomitant expression, on the other hand, of the gene of interest then allows the investigator to evaluate if the activity of the expressed target protein is located upstream or downstream of the initiated signaling event, depending on the readout of the signaling pathway that is obtained. Here, the apoptotic cascade was selected as a defined signaling pathway to demonstrate protocol functionality. Pathogenic bacteria, such as Coxiella burnetii, translocate effector proteins that interfere with host cell death induction in the host cell to ensure bacterial survival in the cell and to promote their dissemination in the organism. The C. burnetii effector protein CaeB effectively inhibits host cell death after induction of apoptosis with UV-light or with staurosporine. To narrow down at which step CaeB interferes with the propagation of the apoptotic signal, selected proteins with well-characterized pro-apoptotic activity were expressed transiently in a doxycycline-inducible manner. If CaeB acts upstream of these proteins, apoptosis will proceed unhindered. If CaeB acts downstream, cell death will be inhibited. The test proteins selected were Bax, which acts at the level of the mitochondria, and caspase 3, which is the major executioner protease. CaeB interferes with cell death induced by Bax expression, but not by caspase 3 expression. CaeB, thus, interacts with the apoptotic cascade between these two proteins.

The method described here is used to induce the apoptotic signaling cascade at defined steps in order to dissect the activity of an anti-apoptotic bacterial effector protein. This method can also be used for inducible expression of pro-apoptotic or toxic proteins, or for dissecting interference with other signaling pathways.

Aplicando um sistema de expressão induzível para estudar interferência de fatores de virulência bacteriana com Sinalização Intracelular

The technique presented here allows one to analyze at which step a target protein, or alternatively a small molecule, interacts with the components of a ...

RNA Purification from Intracellularly Grown Listeria monocytogenes in Macrophage Cells

Analysis of the transcriptome of bacterial pathogens during mammalian infection is a valuable tool for studying genes and factors that mediate infection. However, isolating bacterial RNA from infected cells or tissues is a challenging task, since mammalian RNA mostly dominates the lysates of infected cells. Here we describe an optimized method for RNA isolation of Listeria monocytogenes bacteria growing within bone marrow derived macrophage cells. Upon infection, cells are mildly lysed and rapidly filtered to discard most of the host proteins and RNA, while retaining intact bacteria. Next, bacterial RNA is isolated using hot phenol-SDS extraction followed by DNase treatment. The extracted RNA is suitable for gene transcription analysis by multiple techniques. This method is successfully employed in our studies of Listeria monocytogenes gene regulation during infection of macrophage cells 1-4. The protocol can be easily modified to study other bacterial pathogens and cell types.

RNA Purification from Intracellularly Grown Listeria monocytogenes in Macrophage Cells

Here we describe a method for bacterial RNA isolation from Listeria monocytogenes bacteria growing inside murine macrophages. This technique can be used with other intracellular pathogens and mammalian host cells.

A purificação a partir de ARN intracelularmente Grown<em&gt; Listeria monocytogenes</em&gt; Em macrófagos

Analysis of the transcriptome of bacterial pathogens during mammalian infection is a valuable tool for studying genes and factors that mediate infection. ...

Small RNA Transfection in Primary Human Th17 Cells by Next Generation Electroporation

CD4+ T cells can differentiate into several subsets of effector T helper cells depending on the surrounding cytokine milieu. Th17 cells can be generated from na&#239;ve CD4+ T cells in vitro by activating them in the presence of the polarizing cytokines IL-1&#946;, IL-6, IL-23, and TGF&#946;. Th17 cells orchestrate immunity against extracellular bacteria and fungi, but their aberrant activity has also been associated with several autoimmune and inflammatory diseases. Th17 cells are identified by the chemokine receptor CCR6 and defined by their master transcription factor, ROR&#947;t, and characteristic effector cytokine, IL-17A. Optimized culture conditions for Th17 cell differentiation facilitate mechanistic studies of human T cell biology in a controlled environment. They also provide a setting for studying the importance of specific genes and gene expression programs through RNA interference or the introduction of microRNA (miRNA) mimics or inhibitors. This protocol provides an easy to use, reproducible, and highly efficient method for transient transfection of differentiating primary human Th17 cells with small RNAs using a next generation electroporation device.

Next generation electroporation is an efficient method for transfecting human Th17 cells with small RNAs to alter gene expression and cell behavior.

RNA pequeno Transfecção em células primárias Th17 humano por Next Generation electroporação

CD4+ T cells can differentiate into several subsets of effector T helper cells depending on the surrounding cytokine milieu. Th17 cells can be generated ...

Identification of Coding and Non-coding RNA Classes Expressed in Swine Whole Blood

The advent of innovative and increasingly powerful next generation sequencing techniques has opened new avenues into the ability to examine the underlying gene expression related to biological processes of interest. These innovations not only allow researchers to observe expression from the mRNA sequences that code for genes that effect cellular function, but also the non-coding RNA (ncRNA) molecules that remain untranslated, but still have regulatory functions. Although researchers have the ability to observe both mRNA and ncRNA expression, it has been customary for a study to focus on one or the other. However, when studies are interested in both mRNA and ncRNA expression, many times they use separate samples to examine either coding or non-coding RNAs due to the difference in library preparations. This can lead to the need for more samples which can increase time, consumables, and animal stress. Additionally, it may cause researchers to decide to prepare samples for only one analysis, usually the mRNA, limiting the number of biological questions that can be investigated. However, ncRNAs span multiple classes with regulatory roles that effect mRNA expression. Because ncRNA are important to fundamental biologic processes and disorder of these processes in during infection, they may, therefore, make attractive targets for therapeutics. This manuscript demonstrates a modified protocol for the generation mRNA and non-coding RNA expression libraries, including viral RNA, from a single sample of whole blood. Optimization of this protocol, improved RNA purity, increased ligation for recovery of methylated RNAs, and omitted&#160;size selection, to allow capture of more RNA species.

Here, we present a protocol optimized for the processing of coding (mRNA) and non-coding&#160;(ncRNA) globin reduced RNA-seq libraries from a single whole blood sample.

Identificação de codificação e Classes de RNA não-codificante expressa em suínos, sangue total

The advent of innovative and increasingly powerful next generation sequencing techniques has opened new avenues into the ability to examine the underlying ...

Confocal Imaging of Double-Stranded RNA and Pattern Recognition Receptors in Negative-Sense RNA Virus Infection

Double-stranded (ds) RNA is produced as a replicative intermediate during RNA virus infection. Recognition of dsRNA by host pattern recognition receptors (PRRs) such as the retinoic acid (RIG-I) like receptors (RLRs) RIG-I and melanoma differentiation-associated protein 5 (MDA-5) leads to the induction of the innate immune response. The formation and intracellular distribution of dsRNA in positive-sense RNA virus infection has been well characterized by microscopy. Many negative-sense RNA viruses, including some arenaviruses, trigger the innate immune response during infection. However, negative-sense RNA viruses were thought to produce low levels of dsRNA, which hinders the imaging study of PRR recognition of viral dsRNA. Additionally, infection experiments with highly pathogenic arenaviruses must be performed in high containment biosafety level facilities (BSL-4). The interaction between viral RNA and PRRs for highly pathogenic RNA virus is largely unknown due to the additional technical challenges that researchers need to face in the BSL-4 facilities. Recently, a monoclonal antibody (Mab) (clone 9D5) originally used for pan-enterovirus detection has been found to specifically detect dsRNA with a higher sensitivity than the traditional J2 or K1 anti-dsRNA antibodies. Herein, by utilizing the 9D5 antibody, we describe a confocal microscopy protocol that has been used successfully to visualize dsRNA, viral protein and PRR simultaneously in individual cells infected by arenavirus. The protocol is also suitable for imaging studies of dsRNA and PRR distribution in pathogenic arenavirus infected cells in BSL4 facilities.

Double-stranded RNA produced during RNA virus replication can be recognized by pattern recognition receptors to induce an innate immune response. For negative-sense RNA viruses, the interaction between the low-level dsRNA and PRRs remains unclear. We have developed a confocal microscopy method to visualize arenavirus dsRNA and PRR in individual cells.

Imagem latente confocal de RNA Double-Stranded e receptores de reconhecimento padrão na infecção pelo vírus de RNA de sentido negativo

Double-stranded (ds) RNA is produced as a replicative intermediate during RNA virus infection. Recognition of dsRNA by host pattern recognition receptors ...