Name: functional characterization of carboxylesterases in insecticide resistant house flies, musca domestica
Uploaded: 2018-08-23T14:30:00
Description: Watch this Scientific Journal Video about Functional Characterization of Carboxylesterases in Insecticide Resistant House Flies, Musca Domestica at JoVE.com

1. expressão e isolamento de proteínas do alvo com um sistema de expressão de células de inseto mediada por Baculovirus
<ol><li>Direcionalmente clone sem corte-terminados produtos PCR de proteínas do alvo de moscas domésticas.<ol>
<li>Projetar primers PCR de proteína verde fluorescente (GFP) e o gene MdαE7 casa voar com base em suas sequências e os requisitos especiais do vetor escolhido (tabela 1).</li>
		<li>Usar uma DNA-polimerase termoestável, correcção e primers da etapa 1.1.1 para rea...

<ol>
	<li>Scott, J. 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=Insecticide+resistance+in+house+flies+from+the+United+States:+Resistance+levels+and+frequency+of+pyrethroid+resistance+alleles.">Insecticide resistance in house flies from the United States: Resistance levels and frequency of pyrethroid resistance alleles.</a> Pesticide Biochemistry and Physiology. 107 (3), 377-384 (2013).</li><li>Li, 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+whole+transcriptomal+linkage+analysis+of+gene+co-regulation+in+insecticide+resistant+house+flies,+Musca+domestica.">A whole transcriptomal linkage analysis of gene co-regulation in insecticide resistant house flies, Musca domestica.</a> BMC Genomics. 14, 803 (2013).</li><li>Liu, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insecticide+resistance+in+mosquitoes:+impact,+mechanisms,+and+research+directions.">Insecticide resistance in mosquitoes: impact, mechanisms, and research directions.</a> Annual Review of Entomology. 60, 537-559 (2015).</li><li>Grigoraki, 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=Transcriptome+profiling+and+genetic+study+reveal+amplified+carboxylesterase+genes+implicated+in+temephos+resistance,+in+the+Asian+tiger+mosquito+Aedes+albopictus.">Transcriptome profiling and genetic study reveal amplified carboxylesterase genes implicated in temephos resistance, in the Asian tiger mosquito Aedes albopictus.</a> e0003771. 9, e0003771 (2015).</li><li>Grigoraki, 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=Carboxylesterase+gene+amplifications+associated+with+insecticide+resistance+in+Aedes+albopictus:+Geographical+distribution+and+evolutionary+origin.">Carboxylesterase gene amplifications associated with insecticide resistance in Aedes albopictus: Geographical distribution and evolutionary origin.</a> PLOS Neglected Tropical Diseases. 11, e0005533 (2017).</li><li>Wheelock, C., Shan, G., Ottea, 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+of+carboxylesterases+and+their+role+in+the+metabolism+of+insecticides.">Overview of carboxylesterases and their role in the metabolism of insecticides.</a> Journal of Pesticide Science. 30, 75-83 (2005).</li><li>Feng, X., Li, M., Liu, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Carboxylesterase+genes+in+pyrethroid+resistant+house+flies,+Musca+domestica.">Carboxylesterase genes in pyrethroid resistant house flies, Musca domestica.</a> Insect Biochemistry and Molecular Biology. 92, 30-39 (2018).</li><li>Mosmann, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+colorimetric+assay+for+cellular+growth+and+survival:+application+to+proliferation+and+cytotoxicity+assays.">Rapid colorimetric assay for cellular growth and survival: application to proliferation and cytotoxicity assays.</a> J Immunol Methods. 65 (1-2), 55-63 (1983).</li><li>Jarvis, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Baculovirus-insect+cell+expression+systems.">Baculovirus-insect cell expression systems.</a> Methods in Enzymology. 463, 191-222 (2009).</li><li>Berger, I., Fitzgerald, D. J., Richmond, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Baculovirus+expression+system+for+heterologous+multiprotein+complexes.">Baculovirus expression system for heterologous multiprotein complexes.</a> Nature Biotechnology. 22 (12), 1583 (2004).</li><li>Gong, Y., Li, T., Feng, Y., Liu, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+function+of+two+P450s,+CYP9M10+and+CYP6AA7,+in+the+permethrin+resistance+of+Culex+quinquefasciatus.">The function of two P450s, CYP9M10 and CYP6AA7, in the permethrin resistance of Culex quinquefasciatus.</a> Scientific Reports. 7 (1), 587 (2017).</li><li>Cao, C. W., Zhang, J., Gao, X. W., Liang, P., Guo, H. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Overexpression+of+carboxylesterase+gene+associated+with+organophosphorous+insecticide+resistance+in+cotton+aphids,+Aphis+gossypii+(Glover).">Overexpression of carboxylesterase gene associated with organophosphorous insecticide resistance in cotton aphids, Aphis gossypii (Glover).</a> Pesticide Biochemistry and Physiology. 90 (3), 175-180 (2008).</li><li>Zhang, L., Gao, X., Liang, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Beta-cypermethrin+resistance+associated+with+high+carboxylesterase+activities+in+a+strain+of+house+fly,+Musca+domestica+(Diptera:+Muscidae).">Beta-cypermethrin resistance associated with high carboxylesterase activities in a strain of house fly, Musca domestica (Diptera: Muscidae).</a> Pesticide Biochemistry and Physiology. 89, 65-72 (2007).</li><li>Van Meerloo, J., Kaspers, G. J., Cloos, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell+sensitivity+assays:+the+MTT+assay.">Cell sensitivity assays: the MTT assay.</a> Cancer cell culture. , 237-245 (2011).</li><li>Stockert, J. C., Bl&#225;zquez-Castro, A., Ca&#241;ete, M., Horobin, R. W., Villanueva, &. #. 1. 9. 3. ;. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MTT+assay+for+cell+viability:+Intracellular+localization+of+the+formazan+product+is+in+lipid+droplets.">MTT assay for cell viability: Intracellular localization of the formazan product is in lipid droplets.</a> Acta Histochemica. 114 (8), 785-796 (2012).</li><li>Strober, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Trypan+blue+exclusion+test+of+cell+viability.">Trypan blue exclusion test of cell viability.</a> Current Protocols in Immunology. , (2001).</li><li>Riss, T. L., Moravec, R. A., Niles, A. L., Duellman, S., Benink, H. A., Worzella, T. J., Minor, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell+viability+assays.">Cell viability assays.</a> Assay Guidance Manual. , (2013).</li><li>Wheelock, C. E., Shan, G., Ottea, 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+of+carboxylesterases+and+their+role+in+the+metabolism+of+insecticides.">Overview of carboxylesterases and their role in the metabolism of insecticides.</a> Journal of Pesticide Science. 30 (2), 75-83 (2005).</li><li>Li, X., Schuler, M. A., Berenbaum, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+mechanisms+of+metabolic+resistance+to+synthetic+and+natural+xenobiotics.">Molecular mechanisms of metabolic resistance to synthetic and natural xenobiotics.</a> Annual Review of Entomology. 52, 231-253 (2007).</li><li>Nakamura, Y., 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+in+vitro+metabolism+of+a+pyrethroid+insecticide,+permethrin,+and+its+hydrolysis+products+in+rats.">The in vitro metabolism of a pyrethroid insecticide, permethrin, and its hydrolysis products in rats.</a> Toxicology. 235 (3), 176-184 (2007).</li><li>Kruger, N. 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+Bradford+method+for+protein+quantitation.">The Bradford method for protein quantitation.</a> The protein protocols handbook. , 15-21 (2002).</li><li>Macauley-Patrick, S., Fazenda, M. L., McNeil, B., Harvey, L. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Heterologous+protein+production+using+the+Pichia+pastoris+expression+system.">Heterologous protein production using the Pichia pastoris expression system.</a> Yeast. 22 (4), 249-270 (2005).</li><li>Berger, I., Fitzgerald, D. J., Richmond, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Baculovirus+expression+system+for+heterologous+multiprotein+complexes.">Baculovirus expression system for heterologous multiprotein complexes.</a> Nature Biotechnology. 22 (12), 1583 (2004).</li><li>Terpe, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Overview+of+bacterial+expression+systems+for+heterologous+protein+production:+from+molecular+and+biochemical+fundamentals+to+commercial+systems.">Overview of bacterial expression systems for heterologous protein production: from molecular and biochemical fundamentals to commercial systems.</a> Applied Microbiology and Biotechnology. 72 (2), 211 (2006).</li><li>Bulter, T., 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=Functional+expression+of+a+fungal+laccase+in+Saccharomyces+cerevisiae+by+directed+evolution.">Functional expression of a fungal laccase in Saccharomyces cerevisiae by directed evolution.</a> Applied Microbiology and Biotechnology. 69 (2), 987-995 (2003).</li><li>Stepanenko, A. A., Dmitrenko, V. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pitfalls+of+the+MTT+assay:+Direct+and+off-target+effects+of+inhibitors+can+result+in+over/underestimation+of+cell+viability.">Pitfalls of the MTT assay: Direct and off-target effects of inhibitors can result in over/underestimation of cell viability.</a> Gene. 574 (2), 193-203 (2015).</li></ol>

Nas últimas décadas, sistemas de expressão heteróloga têm sido amplamente utilizados para expressar e isolar grandes quantidades de proteínas, permitindo assim a determinação bioquímica e funcional e caracterização de enzimas em vitro. Até à data, vários sistemas de modelo diferente, incluindo Escherichia colie Pichia pastoris, Sacccharomyces cerevisiae, Spodoptera frugiperda foram adaptados para a expressão da proteína recombinante e a escolha da sistema i...

Resistência de inseticida é atualmente um grande problema de casa fly controle mundial1,2. Os esforços para determinar o mecanismo de resistência de inseticida facilita o melhor entendimento desta questão e, assim, fornecer novas estratégias para efetivamente prevenir ou minimizar a propagação de resistência desenvolvimento3. Carboxylesterases, como uma das enzimas de desintoxicação principais, têm atraído muita atenção por seus papéis em sequestro e metabolizar inseticidas em vários insetos4,5,6. Nosso estudo anterior identificou vários carboxylesterases em moscas domésticas e seus níveis de expressão não foram apenas constitutivamente acima-está regulada na cepa resistente do ALHF, mas também podem ser induzido para maiores níveis em resposta aos tratamentos de permetrina7 . No entanto, as caracterizações funcionais destes genes carboxylesterase em metabolizar inseticidas continuam a ser explorado.
Desde o primeiro relatório no início da década de 19808, um sistema de expressão de gene estrangeira mediada por baculovirus tem sido amplamente empregado devido a sua eficiência de produção de alta proteína e proteína eukaryotic processamento recursos9. Este sistema binário é composto de dois elementos essenciais: o baculovirus recombinante construído entregando estrangeiros genes em células hospedeiras e a expressão em larga escala de proteínas interessadas por células infectadas por baculovirus recombinante. Nas últimas décadas, o sistema de expressão baculovirus mediada por células tem sido amplamente utilizado para produzir milhares de proteínas recombinantes, variando de enzimas citosólica a proteínas de membrana-limite no inseto e10células de mamífero. Nosso estudo anterior com êxito manifestou várias enzimas CYP450 em células de inseto Sf9 com este sistema de11. Neste estudo, temos construído um baculovirus recombinante-carboxylesterase para infectar células de inseto Sf9, explorou a tolerância de célula à permetrina diferentes tratamentos e em grande escala expressa carboxylesterase proteínas em vitro para funcional exploração. Em vez de investigar várias misturas de Isozima carboxylesterase de insetos homogenates adoptado pela anteriores estudos12,13, este sistema de expressão de células de inseto mediada por baculovirus permite a expressão específica e isolamento de proteínas específicas para melhor caracterização das suas propriedades bioquímicas e estruturais.
O ensaio baseado em sal de tetrazólio (MTT) é um método colorimétrico de alta produtividade, desenvolvido e otimizado para medir a viabilidade celular. Este ensaio baseia-se o mecanismo que apenas as células vivas são capazes de metabolizar o reagente MTT amarela a um precipitado de formazan cor roxo escuro, que pode ser analisado colorimetricamente depois dissolvido em solventes orgânicos14, 15. Mais precisos, mas demorados métodos, tais como a exclusão de Trypan azul e a timidina titulação ensaio16,17, vários foram desenvolvidos nos últimos anos. No entanto, o ensaio de MTT baseada em célula ainda atualmente é reconhecido como o método mais rápido e facilmente operado para detectar rapidamente a viabilidade celular. Aqui, usamos o ensaio de MTT para explorar a tolerância celular contra tratamentos insecticidas. A tolerância melhorada de células quando infectadas com baculovirus recombinante carboxylesterase fortemente suporta as funções metabólicas de carboxylesterases aos inseticidas, que por sua vez, sugere sua participação na resistência de inseticida.
Além disso, um ensaio metabólico em vitro foi também realizado neste estudo. Em comparação com ensaios de carboxylesterase geral que usam substratos comuns tais como acetato de α-napthyl (α-at) e β-naftil acetato (β-NA) para refletir a actividades hidrolíticas de carboxylesterases, o estudo metabólico em vitro é considerado como uma maneira exata para medir diretamente as atividades de carboxylesterases em direção a inseticidas18. Este método tem sido empregado com sucesso em vários tipos de insetos para caracterizar vários citocromo P450s em associação com inseticida resistência11,19,20. No entanto, este método ainda não foi aplicado em estudos carboxylesterase. Com a disponibilidade de carboxylesterase proteínas produzidas pelo sistema de expressão mediada por baculovirus, podemos realizar um em vitro estudo metabólico de carboxylesterases em direção a permetrina, que mais pode fornecer fortes evidências do envolvimento de carboxylesterases em conferir resistência piretroide em casa voa.

<table>
	<tbody>
		<tr>
			<td>Q5 High-Fidelity DNA Polymerase</td>
			<td>New England Biolabs inc.</td>
			<td>M0491L</td>
			<td></td>
		</tr>
		<tr>
			<td>QIAquick Gel Extraction Kit</td>
			<td>QIAGEN</td>
			<td>28704</td>
			<td></td>
		</tr>
		<tr>
			<td>pENTR/D-TOPO Cloning Kit, with One Shot TOP10 Chemically Competent E. coli</td>
			<td>Invitrogen by life technology</td>
			<td>K240020</td>
			<td>S.O.C medium and universal M13 sequence primers were included in this kit.</td>
		</tr>
		<tr>
			<td>PureLink HiPure Plasmid Miniprep Kit</td>
			<td>Invitrogen by life technology</td>
			<td>K210002</td>
			<td></td>
		</tr>
		<tr>
			<td>Gateway LR Clonase II Enzyme mix for BaculoDirectTM Kits</td>
			<td>Invitrogen by life technology</td>
			<td>11791-023</td>
			<td></td>
		</tr>
		<tr>
			<td>BaculoDirect C-Term Linear DNA Transfection Kit</td>
			<td>Invitrogen by life technology</td>
			<td>12562-019</td>
			<td>Cellfectin transfection reagent and ganciclovir were included in this kit</td>
		</tr>
		<tr>
			<td>pENTR-CAT plasmid</td>
			<td>Invitrogen by life technology</td>
			<td></td>
			<td>Included in BaculoDirect C-Term Linear DNA Transfection Kit, concentration: 0.5 ug/uL</td>
		</tr>
		<tr>
			<td>Heat inactivated Fetal Bovine Serum, Certified</td>
			<td>Gibco by Life Technologies</td>
			<td>10082-139</td>
			<td></td>
		</tr>
		<tr>
			<td>Sf9 cells in Sf-900 III SFM</td>
			<td>Gibco by Life Technologies</td>
			<td>12659017</td>
			<td></td>
		</tr>
		<tr>
			<td>Insect Cell-PE LB Insect Cell Protein Extraction &#38; Lysis Buffer</td>
			<td>G Biosciences by A Geno Technology Inc</td>
			<td>786-411</td>
			<td></td>
		</tr>
		<tr>
			<td>Sf-900 III SFM (1&#215;) Serum Free Medium Complete</td>
			<td>Gibco by Life Technologies</td>
			<td>12658-019</td>
			<td></td>
		</tr>
		<tr>
			<td>Grace&#39;s Insect Medium, unsupplemented</td>
			<td>Gibco by Life Technologies</td>
			<td>11595030</td>
			<td></td>
		</tr>
		<tr>
			<td>Permethrin (isomers) analytical standard</td>
			<td>SUPELCO by Solutions WithinTM</td>
			<td>442748</td>
			<td></td>
		</tr>
		<tr>
			<td>Methanol (analytical graded)</td>
			<td>Sigma-Aldrich</td>
			<td>67-56-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Acetonitrile (analytical graded)</td>
			<td>Sigma-Aldrich</td>
			<td>75-05-8</td>
			<td></td>
		</tr>
		<tr>
			<td>GHP Acrodisc 25 mm Syringe Filters with 0.45 &#956;m GHP Membrane (HPLC Certified)</td>
			<td>Pall Life Sciences</td>
			<td>21890388</td>
			<td></td>
		</tr>
		<tr>
			<td>Alliance Waters 2695 HPLC System</td>
			<td>Waters</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>T100 Thermal Cycle</td>
			<td>Bio-Rad Laboratories Inc.</td>
			<td>1861096</td>
			<td></td>
		</tr>
		<tr>
			<td>Nanodrop 2000/2000c Spectrophotometers</td>
			<td>ThermoFisher Scientific</td>
			<td>ND2000CLAPTOP</td>
			<td></td>
		</tr>
		<tr>
			<td>Cytation 5 Cell Imaging Multi-Mode Reader</td>
			<td>BioTek</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

functional characterization of carboxylesterases in insecticide resistant house flies, musca domestica

Mediada por Carboxylesterase metabolismo é pensado para jogar um papel importante na resistência de inseticida em vários tipos de insetos. Vários carboxylesterase de genes foram encontrados acima-está regulada em tensão de voar a casa resistente, Considerando que seus papéis em conferir resistência inseticida permaneceram para ser explorado. Aqui, nós projetamos um protocolo para a caracterização funcional de carboxylesterases. Três experimentos de exemplo são apresentados: (1) expressão e isolamento de proteínas carboxylesterase através de um inseto mediada por baculovirus Spodoptera frugiperda (Sf9) sistema de expressão de células; (2) um MTT baseada em célula (3-[4, 5-dimethykthiazol-2-yl] -2, 5-diphenyltetrazolium brometo) ensaio de citotoxicidade para medir a tolerância das células de inseto à permetrina diferentes tratamentos; e (3) em vitro estudos metabólicos para explorar os recursos metabólicos do carboxylesterases em direção a permetrina. O gene carboxylesterase MdαE7 foi clonada de uma casa resistente voar estirpe ALHF e usado para construir um baculovirus recombinante para Sf9 infecção de células. As realidades de célula contra permetrina diferentes tratamentos foram medidas com o ensaio de MTT. A tolerância de célula reforçada do grupo experimental (células de baculovirus infectado MdαE7-recombinante) comparado com os dos grupos controle (CAT-recombinante baculovirus infectados células e células de baculovirus infectados de GFP-recombinante) a permetrina tratamentos sugeriram que os recursos do MdαE7 em metabolizar inseticidas, protegendo assim as células de danos químicos. Além disso, carboxylesterase proteínas foram expressas em células de inseto Sf9 e isoladas para realizar um estudo metabólico em vitro . Nossos resultados indicaram uma significativa em vitro eficiência metabólica de MdαE7 em direção a permetrina, indicando diretamente o envolvimento do carboxylesterases em metabolizar inseticidas e assim conferir resistência inseticida em casa voa.

A viabilidade celular em direção a permetrina diferentes tratamentos (ensaio de MTT)
A citotoxidade de permetrina foi examinada em MdαE7-recombinante baculovirus infectado Sf9 células (grupo experimental) e CAT-recombinante baculovirus (fornecido pelo kit de baculovirus infectado) infectados células (grupos de controle). As tolerâncias de célula reforçada de permetrina em MdαE7 expressando células fortemente apoiar as fun...

Watch this Scientific Journal Video about Functional Characterization of Carboxylesterases in Insecticide Resistant House Flies, Musca Domestica at JoVE.com

Functional Characterization of Carboxylesterases in Insecticide Resistant House Flies, Musca Domestica

Aqui, apresentamos um protocolo para produzir casa voar carboxylesterase proteínas em vitro com um sistema de expressão baculovirus mediada por células de inseto e mais tarde funcionalmente caracterizar seus papéis em metabolisante permetrina, desse modo, conferindo piretroide resistência por estudos baseados em células MTT ensaio e in vitro metabólica.

Caracterização funcional de Carboxylesterases em casa resistente a inseticida moscas, Musca Domestica

Carboxylesterase-mediated metabolism is thought to play a major role in insecticide resistance in various insects. Several carboxylesterase genes were ...

This method can help the key questions in the field of insect toxicology, such as, if all express the metabolic detoxification genes are involved in insecticide resistance? The main advantage of this technique is that it allows to produce larger scales of proteins, and characterize the function of these proteins in metabolizing of insecticides in vitro. Demonstrating the procedures, will be Xuechun Feng, a grad student in my laboratory.Xuechen's PhD research is focused on the characterization of function of carboxyl esterase in parasite resistance of house flies, Musca domestica. To begin, mix one microliter of GFP entry plasma DNA, with five microliters of a commercially available C-term linear DNA in 250 microliter PCR tubes. Next, add two microliters of commercially available lambda recombination mix to each of the PCR tubes.Gently mix the tubes, and incubate them at 25 degrees Celsius overnight. Seed two milliliters of log phase growth insect SF9 cell culture evenly to the wells of a cell culture plate. Then allow the cells to attach for at least three hours at room temperature, in the hood.Using an inverted phase microscope at 250x, check the cell attachment. Then, remove the cell culture medium, and replace it with two milliliters of Grace's insect medium. After this, prepare transfection mixture A and B solutions according to the text protocol.Then gently mix transfection mixtures A and B together by tapping the tubes. Incubate the mixture at room temperature, in the hood, for 35 minutes. Next, add the mixture drop-wise, onto the seeded cells.Seal the wells with tape, and incubate the cells at 27 degrees Celsius, overnight. Replace the two milliliters of Grace's insect medium, with two milliliters of complete growth medium. Then, add 100 micromole Ganciclovir, to each well.Seal the wells with tape, and incubate the cells at 27 degrees Celsius for 72 hours. 72 hours post-infection, collect the medium from each well, and transfer it to 1.5 milliliter centrifuge tubes. Then centrifuge the tubes at 1500 times G, for five minutes at four degrees Celsius.Add one milliliter of complete growth medium to the well, and use a microscope with fluorescent light, to observe the infection signs of cells at the P1 baculovirus amplification stage. Transfer the supernatant into new 1.5 milliliter centrifuge tubes, and store them at four degrees Celsius, in dark conditions. After this, seed two milliliters of log phase growth insect SF9 cell culture, evenly, in the wells of a cell culture plate.Allow the cells to attach for at least three hours at room temperature, in the hood. Inoculate five microliters of P1 virus stock into the cell seeded wells, then, add 100 micromole Ganciclovir to each well. Seal the wells, and incubate the cells for 72 hours at 27 degrees Celsius.First, culture five milliliters of log phase growth insect SF9 cells, with complete growth medium, in T25 non-treated flasks. Then, add 25 microliters of P1 virus stock solution to infect the cell culture, for 48 hours, with gentle shaking, at 27 degrees Celsius. Using acetonitrile, prepare serial dilutions of 100 millimole permethrin.Then, seed 200 microliters of infected cell culture supplemented with 300 microliters of complete growth media, into a 24 well plate. Making sure that permethrin is fully dissolved in the acetonitrile, and evenly delivered into each well of the plate. After adding the permethrin, gently shake the plate to fully mix the permethrin in the medium.After this, seal the plate with tape, and incubate the plate at 27 degrees Celsius, for 48 hours, in dark conditions. Remove the cell culture medium from the plate without disturbing the bottom attached cell layer. Add 200 microliters of the MMT reagent to each well.Then, incubate the plate at 37 degrees Celsius for four hours, until dark purple formazan precipitants form in each well. Add 500 microliters of DMSO to each well, to fully dissolve the precipitants. Then transfer 200 microliters of the dissolved solution, to each well of a 96 well plate.Fully dissolving the precipitate into DMSO is crucial for the accuracy of the results. After adding the DMSO into samples in the plate, the samples will be washed using the pipette, for several times, until the precipitate has been fully dissolved. Finally, use a microplate reader to measure the absorbance values of the plate at 540 nanometers.At the P1 stage, the infection ratio is low. At the P2 stage, the infection ratio was significantly enhanced. At the P3 infection stage, almost all the cells showed symptoms of detachment from the cell culture plate, increases of cell diameter, as well as the cessation of cell growth.Based on the detected absorbance values, the Md alpha E7 expressing cells showed significantly higher viability, compared to the control CAT cells. While conducting this procedure, it is important to prevent cell contamination in all steps, by wiping the surface of stuffs, such as bottles and tubes, with 70 percentage ethanol before conducting the cell experiments. Following this procedure, some other methods, like the homology modeling and dark analysis, can be performed in order to answer additional questions, like the interactions between carboxyl esterase protein and permethrin ligand.This technique paved the way for the researchers in the insect toxicology, to explore the functional characterization of the genes and mechanisms in insecticide resistance of insects. Don't forget that working with insecticide can be very harmful, and precautions, such as gloves and lab coats, should always be taken while conducting these procedures.

Research

JoVE Journal

Biochemistry

Functional Characterization of Carboxylesterases in Insecticide Resistant House Flies, Musca Domestica

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Caracterização estrutural de polissacarídeos de parede celular Medeiros em plantas usando a ritmo

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Bioquímica

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Characterization of Glycoproteins with the Immunoglobulin Fold by X-Ray Crystallography and Biophysical Techniques

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Fluorescent Silver Staining of Proteins in Polyacrylamide Gels

Coloração fluorescente de prata das proteínas em gel de poliacrilamida

Silver staining is a colorimetric technique widely used to visualize protein bands in polyacrylamide gels following sodium dodecyl sulfate-polyacrylamide ...

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The goal of this protocol encompasses the design of chimeric proteins in which distinct regions of a protein are replaced by their corresponding sequences ...

Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles

Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles

Caracterização de transportadores de membrana por expressão heterologous em E. coli e produção de vesículas de membrana

Several methods have been developed to functionally characterize novel membrane transporters. Polyamines are ubiquitous in all organisms, but polyamine ...

SUMO-Binding Entities (SUBEs) as Tools for the Enrichment, Isolation, Identification, and Characterization of the SUMO Proteome in Liver Cancer

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Entidades vinculantes ao SUMO (SUBEs) como ferramentas para enriquecimento, isolamento, identificação e caracterização do Proteome SUMO em Câncer de Fígado

Post-translational modification is a key mechanism regulating protein homeostasis and function in eukaryotic cells. Among all ubiquitin-like proteins in ...

Functional Characterization of RING-Type E3 Ubiquitin Ligases In Vitro and In Planta

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Ubiquitination, as a posttranslational modification of proteins, plays an important regulatory role in homeostasis of eukaryotic cells. The covalent ...

Characterization of Amyloid Structures in Aging C. Elegans Using Fluorescence Lifetime Imaging

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Amyloid fibrils are associated with a number of neurodegenerative diseases such as Huntington&#39;s, Parkinson&#39;s, or Alzheimer&#39;s disease. These ...