Browsing by Subject "Culicidae"

Now showing 1 - 4 of 4
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    Advances in oral RNAi for disease vector mosquito research and control
    (Elsevier, 2020) Wiltshire, Rachel M.; Duman-Scheel, Molly; Medical and Molecular Genetics, School of Medicine
    Mosquito vectors in the genera Anopheles, Aedes, and Culex transmit a variety of medically important pathogens. Current vector control tools are reaching the limits of their effectiveness, necessitating the introduction of innovative vector control technologies. RNAi, which facilitates functional characterization of mosquito genes in the laboratory, could one day be applied as a new method of vector control. Recent advances in the oral administration of microbial-based systems for delivery of species-specific interfering RNA pesticides to mosquitoes may facilitate translation of this technology to the field. Oral RNAi-based pesticides represent a new class of biorational pesticides that could combat increased global incidence of insecticide resistance and which could one day become critical components of integrated human disease vector mosquito control programs.
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    Oral RNAi for Gene Silencing in Mosquitoes: From the Bench to the Field
    (Cold Spring Harbor Laboratory Press, 2022-07-12) Mysore, Keshava; Hapairai, Limb; Realey, Jacob S.; Sun, Longhua; Roethele, Joseph B.; Duman-Scheel, Molly; Medical and Molecular Genetics, School of Medicine
    RNA interference (RNAi) has played a key role in the field of insect functional genomics, a discipline that has enhanced the study of developmental, evolutionary, physiological, and molecular biological phenomena in a wide variety of insects, including disease vector mosquitoes. Here we introduce a recently optimized RNAi procedure in which adult mosquitoes are fed with a colored sugar bait containing small interfering RNA (siRNA). This procedure effectively and economically leads to gene silencing, is technically straightforward, and has been successfully used to characterize a number of genes in adult mosquitoes. We also discuss how, in addition to laboratory applications, this oral RNAi procedure might one day be used in the field for controlling insect pests.
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    The Plasmodium eukaryotic initiation factor-2α kinase IK2 controls the latency of sporozoites in the mosquito salivary glands
    (Rockefeller University Press, 2010) Zhang, Min; Fennell, Clare; Ranford-Cartwright, Lisa; Sakthivel, Ramanavelan; Gueirard, Pascale; Meister, Stephan; Caspi, Anat; Doerig, Christian; Nussenzweig, Ruth S.; Tuteja, Renu; Sullivan, William J., Jr.; Roos, David S.; Fontoura, Beatriz M. A.; Ménard, Robert; Winzeler, Elizabeth A.; Nussenzweig, Victor; Pharmacology and Toxicology, School of Medicine
    Sporozoites, the invasive form of malaria parasites transmitted by mosquitoes, are quiescent while in the insect salivary glands. Sporozoites only differentiate inside of the hepatocytes of the mammalian host. We show that sporozoite latency is an active process controlled by a eukaryotic initiation factor-2alpha (eIF2alpha) kinase (IK2) and a phosphatase. IK2 activity is dominant in salivary gland sporozoites, leading to an inhibition of translation and accumulation of stalled mRNAs into granules. When sporozoites are injected into the mammalian host, an eIF2alpha phosphatase removes the PO4 from eIF2alpha-P, and the repression of translation is alleviated to permit their transformation into liver stages. In IK2 knockout sporozoites, eIF2alpha is not phosphorylated and the parasites transform prematurely into liver stages and lose their infectivity. Thus, to complete their life cycle, Plasmodium sporozoites exploit the mechanism that regulates stress responses in eukaryotic cells.