We would like to thank Abbie Spinner at the California National Primate Research Center for her assistance with flow cytometry. This study was supported by funding from the National Institute of Allergy and Infectious Diseases (NIAID) National Institutes of Health (NIH) AI073745, AI080799, and AI078183.

<ol>
<li>Prior to starting the protocol, it is important to determine that the mosquito cells used in the experiment are healthy and at ~80% confluence if adherent (Figure 1). Overgrown or unhealthy cells will result in low transfection efficiency and will give inconsistent results.</li>
<li>Warm up all media prior to use in a 28&deg;C water bath for 30 minutes. 
	<ol class="lalpha">
<li>A. stephensi MSQ43 cells require E5 medium: MEM, Earle's w/ glutamine, 5% heat inactivated FCS, 0.2% D-glucose, 1% penicillin-streptomycin antibio...

<ol>
	<li>Corby-Harris, V. D. A., Watkins de Jong, L., Pakpour, N., Antonova, Y., Ziegler, R., Ramberg, F., Lewis, E. E., Brown, J. M., Luckhart, S. L., Riehle, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+strategy+for+controlling+malaria+transmission+in+the+mosquito+Anopheles+stephensi.">A novel strategy for controlling malaria transmission in the mosquito Anopheles stephensi.</a> PLOS Pathogens. , (2010).</li><li>Braasch, D. A., Corey, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Locked+nucleic+acid+(LNA):+fine-tuning+the+recognition+of+DNA+and+RNA.">Locked nucleic acid (LNA): fine-tuning the recognition of DNA and RNA.</a> Chem Biol. 8, 1-7 (2001).</li><li>Andrieu-Soler, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stable+transmission+of+targeted+gene+modification+using+single-stranded+oligonucleotides+with+flanking+LNAs.">Stable transmission of targeted gene modification using single-stranded oligonucleotides with flanking LNAs.</a> Nucleic Acids Res. 33, 3733-3742 (2005).</li><li>Parekh-Olmedo, H., Drury, M., Kmiec, E. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeted+nucleotide+exchange+in+Saccharomyces+cerevisiae+directed+by+short+oligonucleotides+containing+locked+nucleic+acids.">Targeted nucleotide exchange in Saccharomyces cerevisiae directed by short oligonucleotides containing locked nucleic acids.</a> Chem Biol. 9, 1073-1084 (2002).</li><li>Rhee, W. J., Santangelo, P. J., Jo, H., Bao, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Target+accessibility+and+signal+specificity+in+live-cell+detection+of+BMP-4+mRNA+using+molecular+beacons.">Target accessibility and signal specificity in live-cell detection of BMP-4 mRNA using molecular beacons.</a> Nucleic Acids Res. 36, e30-e30 (2008).</li><li>Marras, S. A., Kramer, F. R., Tyagi, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genotyping+SNPs+with+molecular+beacons.">Genotyping SNPs with molecular beacons.</a> Methods Mol Biol. 212, 111-128 (2003).</li><li>Tyagi, S., Bratu, D. P., Kramer, F. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multicolor+molecular+beacons+for+allele+discrimination.">Multicolor molecular beacons for allele discrimination.</a> Nat Biotechnol. 16, 49-53 (1998).</li><li>Blandin, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dissecting+the+genetic+basis+of+resistance+to+malaria+parasites+in+Anopheles+gambiae.">Dissecting the genetic basis of resistance to malaria parasites in Anopheles gambiae.</a> Science. 326, 147-150 (2009).</li><li>Niare, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+loci+affecting+resistance+to+human+malaria+parasites+in+a+West+African+mosquito+vector+population.">Genetic loci affecting resistance to human malaria parasites in a West African mosquito vector population.</a> Science. 298, 213-216 (2002).</li><li>Riehle, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Natural+malaria+infection+in+Anopheles+gambiae+is+regulated+by+a+single+genomic+control+region.">Natural malaria infection in Anopheles gambiae is regulated by a single genomic control region.</a> Science. 312, 577-579 (2006).</li></ol>

Here we present an in vitro method and evidence for targeted conversion of a single nucleotide in an episomal gene target following transfection of LNA-ONs into A. stephensi and A. gambiae cells. LNA-ON-mediated gene conversion requires induction of a site-specific DNA repair response; our data indicate that mosquito cells can support this mechanism for site-specific mutagenesis. While the method presented here is based on conversion of an episomal target, our data suggest that LNA-ON-mediated ...

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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>Effectene transfection reagent</td>
<td>&nbsp;</td>
<td>Qiagen</td>
<td>301425</td>
<td>&nbsp;</td>
<tr>
<td>GFP control plasmid (pcDNA6.2-GW/EmGFP-miR-neg)</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>K4935-00</td>
<td>&nbsp;</td>
<tr>
<td>BFP plasmid (pcDNA5/FRT/TO)</td>
<td>&nbsp;</td>
<td>Gift from Dr. Concordet3</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>LNA-ONs </td>
<td>&nbsp;</td>
<td>Gift from Dr. Concordet3</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>MEM, Earle's w/ glutamine</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>11095</td>
<td>&nbsp;</td>
<tr>
<td>Fetal calf serum (FCS)</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>16000</td>
<td>&nbsp;</td>
<tr>
<td>Schneider&#x2019;s Drosophila medium</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>11730</td>
<td>&nbsp;</td>
<tr>
<td>Non-essential amino acids</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>11140</td>
<td>&nbsp;</td>
<tr>
<td>10% D-glucose</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>G5767</td>
<td>&nbsp;</td>
<tr>
<td>Penicillin-streptomycin antibiotic</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>15140</td>
<td>&nbsp;</td>
<tr>
<td>6-well culture plates</td>
<td>&nbsp;</td>
<td>Corning</td>
<td>3516</td>
<td>&nbsp;</td>		</tbody>
		</table>
		</div>

transfection and mutagenesis of target genes in mosquito cells by locked nucleic acid-modified oligonucleotides

Plasmodium parasites, the causative agent of malaria, are transmitted through the bites of infected Anopheles mosquitoes resulting in over 250 million new infections each year. Despite decades of research, there is still no vaccine against malaria, highlighting the need for novel control strategies. One innovative approach is the use of genetically modified mosquitoes to effectively control malaria parasite transmission. Deliberate alterations of cell signaling pathways in the mosquito, via targeted mutagenesis, have been found to regulate parasite development 1. From these studies, we can begin to identify potential gene targets for transformation. Targeted mutagenesis has traditionally relied upon the homologous recombination between a target gene and a large DNA molecule. However, the construction and use of such complex DNA molecules for generation of stably transformed cell lines is costly, time consuming and often inefficient. Therefore, a strategy using locked nucleic acid-modified oligonucleotides (LNA-ONs) provides a useful alternative for introducing artificial single nucleotide substitutions into episomal and chromosomal DNA gene targets (reviewed in 2). LNA-ON-mediated targeted mutagenesis has been used to introduce point mutations into genes of interest in cultured cells of both yeast and mice 3,4. We show here that LNA-ONs can be used to introduce a single nucleotide change in a transfected episomal target that results in a switch from blue fluorescent protein (BFP) expression to green fluorescent protein (GFP) expression in both Anopheles gambiae and Anopheles stephensi cells. This conversion demonstrates for the first time that effective mutagenesis of target genes in mosquito cells can be mediated by LNA-ONs and suggests that this technique may be applicable to mutagenesis of chromosomal targets in vitro and in vivo.

Watch this Scientific Journal Video about Transfection and Mutagenesis of Target Genes in Mosquito Cells by Locked Nucleic Acid-modified Oligonucleotides at JoVE.com

Transfection and Mutagenesis of Target Genes in Mosquito Cells by Locked Nucleic Acid-modified Oligonucleotides

Oligonucleotides can be used to site specifically substitute a single nucleotide of transfected target genes in both Anopheles gambiae and Anopheles stephensi cells.

Plasmodium parasites, the causative agent of malaria, are transmitted through the bites of infected Anopheles mosquitoes resulting in over 250 million new ...

transfection-mutagenesis-target-genes-mosquito-cells-locked-nucleic

Research

JoVE Journal

Immunology and Infection

10.3K 조회수.  University of California, Davis. Oligonucleotides은 특히 모두 transfected 대상 유전자의 단일 염기 대체 사이트로 사용할 수 있습니다 아노 펠 레스 gambiae과 아노 펠 레스 stephensi 세포.