RNAi mediada silenciamento de genes em mosquitos exige preparação prévia e purificação de dsRNAs específicos que visam o gene de interesse. Para a síntese de dsRNA, recomendamos o kit Megascript Ambion que faz uso de uma RNA polimerase T7 mediada por reação in vitro de transcrição. Para a purificação de dsRNA, recomendamos o kit Qiagen RNeasy. Amostras de dsRNA devem ser quantificados e ajustado a 3 mcg / mL em água. Outros materiais que você vai precisar incluir: com pontas finas pinças, lâmina de vidro, agulhas de vidro microcapilar, microinjetor (usamos Nanoject Drummond II), um microscópio de luz montada sobre um bloco de frio, uma coberta de vidro prato de Petri, toalhas de papel e um balde de gelo . Você também vai precisar de uma maneira de coletar mosquitos e recipiente adequado para eles, juntamente com uma fonte de alimento, tais como algodão embebido em sacarose 10%. <ol><li> Recolher os seus mosquitos. Usando um aspirador movido a bateria, coletar os mosquitos que deseja injetar. Conecte o bico com uma toalha de papel ou algodão de forma que nenhum mosquito pode escapar e remover o reservatório. Uma vez que as temperaturas frias anestesiar os mosquitos, enterre o reservatório em um balde de gelo e esperar 5-10 minutos para os mosquitos parar de se mover. Anestesiados também pode ser feito colocando o reservatório em uma sala fria ou geladeira ou usando CO 2. Durante esses 5-10 minutos, continue para a próxima etapa. </li><li> Prepare sua área de trabalho. Definir um bloco de superfície plana fria a 2 ° C e coloque uma lâmina de vidro sobre ela. Este é o lugar onde os mosquitos vai descansar enquanto você injetá-las. Coloque uma agulha de vidro para o microinjetor e usar sua pinça para quebrar a ponta da agulha para a largura desejada. É importante que a largura é grande o suficiente para permitir espaço suficiente para líquido para fluir através de uma taxa razoável, mas é estreito o suficiente para causar uma ferida mínimos durante a injeção. A ponta da agulha bom será estreito o suficiente para dobrar um pouco, mas não quebrar. Definir o seu equipamento de injeção para o volume de saída desejada (por RNAi, usamos 69 nL). Submergir a ponta de sua agulha em sua amostra e desenhar a sua amostra de líquido para dentro da agulha usando as instruções do fabricante. A amostra de líquido pode ser uma solução dsRNA, suspensão bacteriana, ou outros, o processo de injeção é a mesma para todos. Incorporar uma placa de Petri de vidro no balde de gelo para que o fundo do prato está completamente em contato com o gelo. Isto é onde você irá colocar os mosquitos até que você esteja pronto para injetá-las. </li><li> Prepare o seu mosquitos. Transferir 50-100 mosquitos do reservatório para a placa de Petri de vidro. Use sua pinça para thin-los em uma única camada, certificando-se a maioria tem contato com o fundo frio do prato para mantê-los anestesiados. Cobrir esses mosquitos com o prato tampa quando não estiver em uso. Retorno do reservatório para o balde de gelo para manter o resto dos mosquitos anestesiados. </li><li> Monte mosquitos em bloco frio. Use sua pinça de ponta fina para transferir os mosquitos um de cada vez do prato para o slide de vidro montada no bloco frio sob o microscópio de luz. Lidar com os mosquitos delicadamente, de preferência pelas pernas. Line up até 30 mosquitos lado a lado no slide, certificando-se que você pode começar a cada um com o microinjetor e certificando-se cada um faz o contato com a lâmina fria. Verifique se o seu mosquitos estão alinhados em ordem, para que enquanto você vai longitudinalmente você sabe que tem e que não tenham sido injetado. Deixe outros mosquitos abordados na placa de Petri refrigeradas. </li><li> Injetar o seu primeiro grupo de mosquitos. Segure o de ponta fina pinça com ponta em uma mão e segurar o microinjetor no outro lado como um lápis. Use a pinça para mover o mosquito que você precisa (segurá-los pelas pernas para evitar a lesão) e para manter o mosquito firme como você injetar. Isso funciona melhor se você usar a pinça para apoiar um dos lados do mosquito como você injetar a partir do outro lado. Insira cuidadosamente apenas a ponta da agulha para tórax mosquito. O melhor é injetar uma parte tensa ainda fina da cutícula para minimizar o prejuízo. Além disso, evitar injetar muito profundamente, você quer apenas a ponta de estar dentro do tórax; injeções causa mais profunda feridas maior que irá comprometer a sobrevivência. Uma vez que a ponta da agulha está na posição, pressione e solte o pedal do aparelho microinjetor que vai entregar o seu volume pré-definido de dsRNA. Espere um ou dois segundos e retire a agulha do mosquito. Se uma gota de líquido aparece fora do local da ferida, aguarde alguns segundos para que possa ser absorvida na ferida. Se ele não absorve dentro de alguns segundos, descartamos o mosquito e tente novamente. Continuar o processo de injeção para todos os mosquitos em sua lâmina de vidro. </li><li> Armazenar seus mosquitos. Quando terminar, coloque o seu mosquitos injetados dentro de recipientes rotulados (nós preferimos um pint copos de cera revestido de papelão cobertos pormalha de redes e presa com tiras de borracha e uma tampa de papelão). </li><li> Continue injeções até terminar. Continue para colocar mosquitos no slide, injetar e transferência para copos até que você tenha o tamanho da amostra que você deseja. Responsáveis ​​por algumas mortes iniciantes terão muitos mosquitos morrem a partir do trauma da injeção. Isto irá melhorar com a prática até quase 100% do seu mosquitos sobrevivem injeção. </li><li> Quando terminar, coloque um dobrado, papel toalha molhada sobre o cálice, juntamente com uma fonte de alimento e cobrir os copos com algo a reter a umidade, tais como plástico ou uma tampa de plástico Petri. Mosquitos injetados são propensas a secar assim que a umidade fornecida pela toalha molhada e retido pelo plástico irá ajudar a evitar isso. </li><li> Coloque seu mosquitos em uma câmara de ambiente controlado para a incubação. </li></ol> Nota: Eficiência de silenciamento do gene é altamente variável e depende de uma série de fatores, incluindo transcrição e proteínas turn-over, as taxas de absorção e eficiência dsRNA pelas células e órgãos. Descobrimos que o silenciamento começa tão cedo quanto uma injeção de pós dia, e pode durar até seis dias após a injecção. Utilização de métodos de detecção de transcrição e proteínas, tais como PCR quantitativo e Western blotting para validar silenciar. Nota: Há diversas variações em várias etapas da injeção mosquito e RNAi mediada técnica de silenciamento gênico. Algumas variações são descritas por: Boisson, et al (2006) e Blandin, et al (2002)...

<ol>
	<li>Boisson, ., 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> , (2006).</li><li>Blandin, ., 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> , (2002).</li></ol>

Eficiência do silenciamento do gene é altamente variável e depende de uma série de fatores, incluindo transcrição e proteínas turn-over, as taxas de absorção e eficiência dsRNA pelas células e órgãos. Descobrimos que o silenciamento começa tão cedo quanto uma injeção de pós dia e pode durar até seis dias após a injecção. Utilização de métodos de detecção de transcrição e proteínas, tais como PCR quantitativo e Western blotting para validar silenciar.

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		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>Megascript</td>
<td>kit</td>
<td>Ambion</td>
<td>&nbsp;</td>
<td>for dsRNA synthesis; T7 RNA polymerase-mediated in vitro transcription reaction</td>
</tr>
<tr>
<td>RNeasy</td>
<td>&nbsp;</td>
<td>Qiagen</td>
<td>&nbsp;</td>
<td>For dsRNA purification</td>
</tr>
<tr>
<td>dsRNA</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>should be quantified and adjusted to 3 &#x03BC;g/ &#x03BC;L in water</td>
</tr>
<tr>
<td>fine-tipped forceps</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>glass slide</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>glass microcapillary needles</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>microinjector</td>
<td>&nbsp;</td>
<td>Drummond</td>
<td>Nanoject II</td>
<td>&nbsp;</td>
<tr>
<td>light microscope</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>mounted above a cold block</td>
</tr>
<tr>
<td>Petri dish</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>covered, glass</td>
</tr>
<tr>
<td>paper towels</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>10% sucrose</td>
<td>food</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>A. gambiae</td>
<td>Animal</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>mosquitos</td>
</tr>		</tbody>
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		</div>

protocol for rnai assays in adult mosquitoes (a. gambiae)

Reversa abordagens genéticas têm-se revelado extremamente útil para determinar quais genes de resistência a patógenos underly vetor em mosquitos. Este protocolo de vídeo ilustra um método utilizado pelo laboratório Dimopoulos para injetar dsRNA em mosquitos Anopheles gambiae, que abrigam o parasita da malária. A técnica de manipular a configuração da injeção e injetar dsRNA no tórax é ilustrado.

Watch this Scientific Journal Video about Protocol for RNAi Assays in Adult Mosquitoes A. gambiae at JoVE.com

Protocol for RNAi Assays in Adult Mosquitoes A. gambiae

Protocolo para Ensaios RNAi em mosquitos adultos (A. gambiae)

Reverse genetic approaches have proven extremely useful for determining  which genes underly resistance to vector pathogens in mosquitoes.  This video ...

protocol-for-rnai-assays-in-adult-mosquitoes-a-gambiae

Research

JoVE Journal

Biology

Protocol for RNAi Assays in Adult Mosquitoes (A. gambiae)

12.6K visualizações.  Johns Hopkins University. Reversa abordagens genéticas têm-se revelado extremamente útil para determinar quais genes de resistência a patógenos underly vetor em mosquitos. Este protocolo de vídeo ilustra um método utilizado pelo laboratório Dimopoulos para injetar dsRNA em mosquitos Anopheles gambiae, que abrigam o parasita da malária. A técnica de manipular a configuração da injeção e injetar dsRNA no tórax é ilustrado.

Vídeo: Protocol for RNAi Assays in Adult Mosquitoes A. gambiae

Protocol for Dengue Infections in Mosquitoes (A. aegypti) and Infection Phenotype Determination

The purpose of this procedure is to infect the Aedes mosquito with dengue virus in a laboratory condition and examine the infection level and dynamic of the virus in the mosquito tissues. This protocol is routinely used for studying mosquito-virus interactions, especially for identification of novel host factors that are able to determine vector competence. The entire experiment must be conducted in a BSL2 laboratory. Similar to Plasmodium falciparum infections, proper attire including gloves and lab coat must be worn at all times. After the experiment, all the materials that came in contact with the virus need to be treated with 75% ethanol and bleached before proceeding with normal washing. All other materials need to be autoclaved before discarding them.

Protocol for Dengue Infections in Mosquitoes A. aegypti and Infection Phenotype Determination

Once a gene is identified as potentially refractory for the dengue virus, it must be evaluated for it's role in preventing viral infections within the mosquito. This protocol illustrates how the extent of dengue infections of mosquitoes can be assayed. The techniques for growing up the virus in culture, membrane feeding mosquitoes human blood, and assaying viral titers in the mosquito midgut are demonstrated.

Protocolo para infecções por dengue em mosquitos (A. aegypti) e Determinação Fenótipo Infecção

The purpose of this procedure is to infect the Aedes mosquito with dengue virus in a laboratory condition and examine the infection level and dynamic of ...

Biologia

Protocol for Mosquito Rearing (A. gambiae)

This protocol describes mosquito rearing in the insectary. The insectary rooms are maintained at 28&deg;C and ~80% humidity, with a 12 hr. day/night cycle. For this procedure, you'll need mosquito cages, 10% sterile sucrose solution, paper towels, beaker, whatman filter paper, glass feeders, human blood and serum, water bath, parafilm, distilled water, clean plastic trays, mosquito food (described below), mosquito net to cover the trays, vacuum, and a collection chamber to collect adults.

Protocol for Mosquito Rearing A. gambiae

This video illustrates the general techniques used to rear Anopheles gambiae in the laboratory. The methods for caring for laboratory mosquitoes are demonstrated through all stages of the organism's life cycle from larvae to pupae to blood-feeding adults.

Protocolo para a Criação Mosquito (A. gambiae)

This protocol describes mosquito rearing in the insectary. The insectary rooms are maintained at 28&deg;C and ~80% humidity, with a 12 hr. day/night ...

Protocol for Plasmodium falciparum Infections in Mosquitoes and Infection Phenotype Determination

Once a gene is identified as potentially refractory for malaria, it must be evaluated for its role in preventing Plasmodium infections within the mosquito.    This protocol illustrates how the extent of plasmodium infections of mosquitoes can be assayed.  The techniques for preparing the gametocyte culture, membrane feeding mosquitoes human blood, and assaying viral titers in the mosquito midgut are demonstrated.

Once a gene is identified as potentially refractory for malaria, it must be evaluated for its role in preventing Plasmodium infections within the mosquito. This protocol illustrates how the extent of plasmodium infections of mosquitoes can be assayed. The techniques for preparing the gametocyte culture, membrane feeding mosquitoes human blood, and assaying viral titers in the mosquito midgut are demonstrated.

Protocolo para Infecções Plasmodium falciparum em mosquitos e Infecção Determinação Fenótipo

Once a gene is identified as potentially refractory for malaria, it must be evaluated for its role in preventing Plasmodium infections within the ...

Building a Better Mosquito: Identifying the Genes Enabling Malaria and Dengue Fever Resistance in A. gambiae and A. aegypti Mosquitoes

In this interview, George Dimopoulos focuses on the physiological mechanisms used by mosquitoes to combat Plasmodium falciparum and dengue virus infections.   Explanation is given for how key refractory genes, those genes conferring resistance to vector pathogens, are identified in the mosquito and how this knowledge can be used to generate transgenic mosquitoes that are unable to carry the malaria parasite or dengue virus.

In this interview, George Dimopoulos focuses on the physiological mechanisms used by mosquitoes to combat Plasmodium falciparum and dengue virus infections. Explanation is given for how key refractory genes, those genes conferring resistance to vector pathogens, are identified in the mosquito and how this knowledge can be used to generate transgenic mosquitoes that are unable to carry the malaria parasite or dengue virus.

Construção de uma melhor Mosquito: identificar os genes habilitação Malária e Dengue Febre Resistência em A. gambiae e A. aegypti mosquitos

In this interview, George Dimopoulos focuses on the physiological mechanisms used by mosquitoes to combat Plasmodium falciparum and dengue virus ...

MISSION esiRNA for RNAi Screening in Mammalian Cells

RNA interference (RNAi) is a basic cellular mechanism for the control of gene expression. RNAi is induced by short double-stranded RNAs also known as small interfering RNAs (siRNAs). The short double-stranded RNAs originate from longer double stranded precursors by the activity of Dicer, a protein of the RNase III family of endonucleases. The resulting fragments are components of the RNA-induced silencing complex (RISC), directing it to the cognate target mRNA. RISC cleaves the target mRNA thereby reducing the expression of the encoded protein1,2,3. RNAi has become a powerful and widely used experimental method for loss of gene function studies in mammalian cells utilizing small interfering RNAs.
Currently two main methods are available for the production of small interfering RNAs. One method involves chemical synthesis, whereas an alternative method employs endonucleolytic cleavage of target specific long double-stranded RNAs by RNase III in vitro. Thereby, a diverse pool of siRNA-like oligonucleotides is produced which is also known as endoribonuclease-prepared siRNA or esiRNA. A comparison of efficacy of chemically derived siRNAs and esiRNAs shows that both triggers are potent in target-gene silencing. Differences can, however, be seen when comparing specificity. Many single chemically synthesized siRNAs produce prominent off-target effects, whereas the complex mixture inherent in esiRNAs leads to a more specific knockdown10.
In this study, we present the design of genome-scale MISSION esiRNA libraries and its utilization for RNAi screening exemplified by a DNA-content screen for the identification of genes involved in cell cycle progression. We show how to optimize the transfection protocol and the assay for screening in high throughput. We also demonstrate how large data-sets can be evaluated statistically and present methods to validate primary hits. Finally, we give potential starting points for further functional characterizations of validated hits.

Here we use a human esiRNA library in a high-throughput screen for genes involved in cell division. We demonstrate how to set up and conduct an esiRNA screens, as well as how to analyze and validate the results.

EsiRNA MISSÃO para a seleção RNAi em células de mamíferos

RNA interference (RNAi) is a basic cellular mechanism for the control of gene expression. RNAi is induced by short double-stranded RNAs also known as ...

Bacterial Delivery of RNAi Effectors: Transkingdom RNAi

RNA interference (RNAi) represents a high effective mechanism for specific inhibition of mRNA expression. Besides its potential as a powerful laboratory tool, the RNAi pathway appears to be promising for therapeutic utilization. For development of RNA interference (RNAi)-based therapies, delivery of RNAi-mediating agents to target cells is one of the major obstacles. A novel strategy to overcome this hurdle is transkingdom RNAi (tkRNAi). This technology uses non-pathogenic bacteria, e.g. Escherichia coli, to produce and deliver therapeutic short hairpin RNA (shRNA) into target cells to induce RNAi. A first-generation tkRNAi-mediating vector, TRIP, contains the bacteriophage T7 promoter for expression regulation of a therapeutic shRNA of interest. Furthermore, TRIP has the Inv locus from Yersinia pseudotuberculosis that encodes invasin, which permits natural noninvasive bacteria to enter &beta;1-integrin-positive mammalian cells and the HlyA gene from Listeria monocytogenes, which produces listeriolysin O. This enzyme allows the therapeutic shRNA to escape from entry vesicles within the cytoplasm of the target cell. TRIP constructs are introduced into a competent non-pathogenic Escherichia coli strain, which encodes T7 RNA polymerase necessary for the T7 promoter-driven synthesis of shRNAs. A well-characterized cancer-associated target molecule for different RNAi strategies is ABCB1 (MDR1/P-glycoprotein, MDR1/P-gp). This ABC-transporter acts as a drug extrusion pump and mediates the "classical" ABCB1-mediated multidrug resistance (MDR) phenotype of human cancer cells which is characterized by a specific cross resistance pattern. Different ABCB1-expressing MDR cancer cells were treated with anti-ABCB1 shRNA expression vector bearing E. coli. This procedure resulted in activation of the RNAi pathways within the cancer cells and a considerable down regulation of the ABCB1 encoding mRNA as well as the corresponding drug extrusion pump. Accordingly, drug accumulation was enhanced in the pristine drug-resistant cancer cells and the MDR phenotype was reversed. By means of this model the data provide the proof-of-concept that tkRNAi is suitable for modulation of cancer-associated factors, e.g. ABCB1, in human cancer cells.

For development of RNA interference (RNAi)-based therapies, a novel strategy was developed, transkingdom RNAi (tkRNAi). This technology uses non-pathogenic bacteria to produce and deliver therapeutic short hairpin RNA (shRNA) into target cells. Here, tkRNAi was successfully applied for reversal of classical ABCB1-mediated multidrug resistance (MDR) of cancer cells.

Entrega bacteriana de RNAi Effectors: Transkingdom RNAi

RNA interference (RNAi) represents a high effective mechanism for specific inhibition of mRNA expression. Besides its potential as a powerful laboratory ...

RNAi-mediated Gene Knockdown and In Vivo Diuresis Assay in Adult Female Aedes aegypti Mosquitoes

This video protocol demonstrates an effective technique to knockdown a particular gene in an insect and conduct a novel bioassay to measure excretion rate. This method can be used to obtain a better understanding of the process of diuresis in insects and is especially useful in the study of diuresis in blood-feeding arthropods that are able to take up huge amounts of liquid in a single blood meal. 
This RNAi-mediated gene knockdown combined with an in vivo diuresis assay was developed by the Hansen lab to study the effects of RNAi-mediated knockdown of aquaporin genes on Aedes aegypti mosquito diuresis1. 
The protocol is setup in two parts: the first demonstration illustrates how to construct a simple mosquito injection device and how to prepare and inject dsRNA into the thorax of mosquitoes for RNAi-mediated gene knockdown. The second demonstration illustrates how to determine excretion rates in mosquitoes using an in vivo bioassay.

RNAi-mediated Gene Knockdown and In Vivo Diuresis Assay in Adult Female Aedes aegypti Mosquitoes

In this protocol we combine RNAi-mediated gene silencing with an in vivo diuresis assay to study the effects knockdown of genes of interest has on mosquito fluid excretion.

RNAi mediada knockdown do gene e<em&gt; In Vivo</em&gt; Ensaio diurese no Feminino Adulto<em&gt; Aedes aegypti</em&gt; Os mosquitos

This video protocol demonstrates an effective technique to knockdown a particular gene in an insect and conduct a novel bioassay to measure excretion ...

Endurance Training Protocol and Longitudinal Performance Assays for Drosophila melanogaster

One of the most pressing problems facing modern medical researchers is the surging levels of obesity, with the consequent increase in associated disorders such as diabetes and cardiovascular disease 1-3. An important topic of research into these associated health problems involves the role of endurance exercise as a beneficial intervention.
Exercise training is an inexpensive, non-invasive intervention with several beneficial results, including reduction in excess body fat 4, increased insulin sensitivity in skeletal muscle 5, increased anti-inflammatory and antioxidative responses 6, and improved contractile capacity in cardiomyocytes 7. Low intensity exercise is known to increase mitochondrial activity and biogenesis in humans 8 and mice, with the transcriptional coactivator PGC1-&alpha; as an important intermediate 9,10. 
Despite the importance of exercise as a tool for combating several important age-related diseases, extensive longitudinal genetic studies have been impeded by the lack of an endurance training protocol for a short-lived genetic model species. The variety of genetic tools available for use with Drosophila, together with its short lifespan and inexpensive maintenance, make it an appealing model for further study of these genetic mechanisms. With this in mind we have developed a novel apparatus, known as the Power Tower, for large scale exercise-training in Drosophila melanogaster 11. The Power Tower utilizes the flies' instinctive negative geotaxis behavior to repetitively induce rapid climbing. Each time the machine lifts, then drops, the platform of flies, the flies are induced to climb. Flies continue to respond as long as the machine is in operation or until they become too fatigued to respond. Thus, the researcher can use this machine to provide simultaneous training to large numbers of age-matched and genetically identical flies. Additionally, we describe associated assays useful to track longitudinal progress of fly cohorts during training.

Endurance Training Protocol and Longitudinal Performance Assays for Drosophila melanogaster

We describe the first endurance training protocol for an important genetic model species, Drosophila melanogaster, and outline several assays to chart improvements in mobility following training.

Protocolo de treinamento de resistência e Ensaios de desempenho longitudinal para Drosophila melanogaster

One of the most pressing problems facing modern medical researchers is the surging levels of obesity, with the consequent increase in associated disorders ...

A Multi-detection Assay for Malaria Transmitting Mosquitoes

The Anopheles gambiae species complex includes the major malaria transmitting mosquitoes in Africa. Because these species are of such medical importance, several traits are typically characterized using molecular assays to aid in epidemiological studies. These traits include species identification, insecticide resistance, parasite infection status, and host preference. Since populations of the Anopheles gambiae complex are morphologically indistinguishable, a polymerase chain reaction (PCR) is traditionally used to identify species. Once the species is known, several downstream assays are routinely performed to elucidate further characteristics. For instance, mutations known as KDR in a para gene confer resistance against DDT and pyrethroid insecticides. Additionally, enzyme-linked immunosorbent assays (ELISAs) or Plasmodium parasite DNA detection PCR assays are used to detect parasites present in mosquito tissues. Lastly, a combination of PCR and restriction enzyme digests can be used to elucidate host preference (e.g., human vs. animal blood) by screening the mosquito bloodmeal for host-specific DNA. We have developed a multi-detection assay (MDA) that combines all of the aforementioned assays into a single multiplex reaction genotyping 33SNPs for 96 or 384 samples at a time. Because the MDA includes multiple markers for species, Plasmodium detection, and host blood identification, the likelihood of generating false positives or negatives is greatly reduced from previous assays that include only one marker per trait. This robust and simple assay can detect these key mosquito traits cost-effectively and in a fraction of the time of existing assays.

Malaria transmitting mosquitoes have a number of epidemiologically important characteristics that can only be detected using molecular techniques. Utilizing a MALDI-TOF based SNP genotyping platform, we developed an assay for simultaneously detecting multiple key traits (species, insecticide resistance, parasite infection and host choice) of malaria vectors.

Um ensaio para detecção multi-malária mosquitos transmissores

The Anopheles gambiae species complex includes the major malaria transmitting mosquitoes in Africa. Because these species are of such medical importance, ...

RNAi Trigger Delivery into Anopheles gambiae Pupae

RNA interference (RNAi), a naturally occurring phenomenon in eukaryotic organisms, is an extremely valuable tool that can be utilized in the laboratory for functional genomic studies. The ability to knockdown individual genes selectively via this reverse genetic technique has allowed many researchers to rapidly uncover the biological roles of numerous genes within many organisms, by evaluation of loss-of-function phenotypes. In the major human malaria vector Anopheles gambiae, the predominant method used to reduce the function of targeted genes involves injection of double-stranded (dsRNA) into the hemocoel of the adult mosquito. While this method has been successful, gene knockdown in adults excludes the functional assessment of genes that are expressed and potentially play roles during pre-adult stages, as well as genes that are expressed in limited numbers of cells in adult mosquitoes. We describe a method for the injection of Serine Protease Inhibitor 2 (SRPN2) dsRNA during the early pupal stage and validate SRPN2 protein knockdown by observing decreased target protein levels and the formation of melanotic pseudo-tumors in SRPN2 knockdown adult mosquitoes. This evident phenotype has been described previously for adult stage knockdown of SRPN2 function, and we have recapitulated this adult phenotype by SRPN2 knockdown initiated during pupal development. When used in conjunction with a dye-labeled dsRNA solution, this technique enables easy visualization by simple light microscopy of injection quality and distribution of dsRNA in the hemocoel.

RNAi Trigger Delivery into Anopheles gambiae Pupae

RNA interference (RNAi) is an extremely valuable tool for uncovering gene function. However, the ability to target genes using RNAi during pre-adult stages is limited in the major human malaria vector Anopheles gambiae. We describe an RNAi protocol to reduce gene function via direct injection during pupal development.

RNAi gatilho para o interior<em&gt; Anopheles gambiae</em&gt; As pupas

RNA interference (RNAi), a naturally occurring phenomenon in eukaryotic organisms, is an extremely valuable tool that can be utilized in the laboratory ...