LAB

Research

In the Hansen lab we do basic research in mosquito molecular biology, molecular physiology, and insect endocrinology.We use the yellow fever mosquito Aedes aegypti as a model invertebrate. We are interested in the molecular mechanisms by which cells and tissues sense nutrients and in response activate signal transduction pathways which regulate expression and/or deactivation of mosquito genes.

Specific research projects include: the characterization of the mosquito transportome (membrane receptors and channels) in the fat body before and after a blood meal and the role of forkhead box (Fox) transcription factors in the fat body. We are located at the second floor of Foster Hall.

Why we study mosquitoes?

Mosquitoes are vectors for some of the most devastating diseases known to humanity since its early history. During the 1950s and 1960s mosquito-borne diseases were thought to have been brought under control through reduction of mosquito populations by large-scale vector control programs and anti malarial drugs. However, a resurgence of the diseases began during the late 1970s and continues to this day due to a complex array of factors such as mosquito pesticide resistance, lack of effective vaccines, parasite resistance to drugs, and political mismanagement.
Today, malaria alone affects 200 to 300 Million people, every year and claims the lives of one to three million humans, especially young children in sub-Saharan Africa. It is estimated that there are worldwide more than 100 million cases of Dengue Fever every year along with several hundreds of thousand cases of the more severe form Dengue Hemorrhagic Fever. Dengue viruses are transmitted by the yellow fever mosquito Aedes aegypti. Today, Dengue is the most important mosquito-borne viral disease affecting humans with a global distribution comparable with malaria. Another example that demonstrates the deadly potential of newly-emerging mosquito-transmitted diseases is the rapid spread of West Nile Virus across the continental US.
The reproductive biology of mosquitoes is tightly linked to their ability to transmit disease pathogens due to the fact that mosquitoes need blood for egg production. Therefore, a detailed understanding of reproductive processes on a molecular level is indispensable in order to identify new ways to disrupt the process of disease transmission. Illumination of the molecular biology underlying mosquito reproduction will pave the way for the development of novel vector control strategies with the ultimate goal of eradicating mosquito-transmitted diseases.

Selected publications

Drake L.L., Boudko D.Y., Marinotti O., Carpenter V.K., Dawe A.L., and Hansen, I.A. The Aquaporin Gene Family of the Yellow Fever Mosquito, Aedes aegypti. PLoS ONE 5(12): e15578. doi:10.1371/journal.pone.0015578 (2010)

Shiao, S., Hansen, I.A., Raikhel, A.S., Effect of Larval Nutrition and Juvenile Hormone on the Target of Rapamycin Signaling and Multiple Blood Meals in Aedes aegypti. J Insect Physiol. 54(1), 231-9 (2008).

Roy, S.G., Hansen, I.A., Raikhel, A.S., Effect of insulin and 20-hydroxyecdysone in the fat body of the yellow fever mosquito, Aedes aegypti. Insect Biochem. Mol. Biol. 37(12), 1317-26 (2007).

Hansen, I.A., Sieglaff, D.H., Munro, J.B., Shiao, S., Lee, I.W., Heraty, J.M., Raikhel, A.S., Forkhead transcription factors regulate mosquito reproduction. Insect Biochem. Mol. Biol. 37, 985-97 (2007).

Attardo, G.M., Hansen, I.A., Shiao, S.H., and Raikhel, A.S. Identification of Two Cationic Amino Acid Transporters required for Nutritional Signaling during Mosquito Reproduction. J. Experimental Biol. 209, 3071-8 (2006).

Park, J.H., Attardo, G.M., Hansen, I.A., and Raikhel A.S. GATA factor translation is the final downstream step in the amino acid/TOR-mediated vitellogenin gene expression in the anautogenous mosquito Aedes aegypti. J. Biol. Chem. 281, 11167-76 (2006).

Hansen, I.A., Attardo, G.M., Roy, S.G. & Raikhel, A.S. Target of rapamycin (TOR)-dependent activation of S6 kinase is a central step in the transduction of nutritional signals during egg development in a mosquito. J. Biol. Chem. 280, 20565-72 (2005).

Hansen, I.A., Attardo, G.M., Park, J.H., Peng, Q. & Raikhel, A.S. Target of rapamycin-mediated amino acid signaling in mosquito anautogeny. Proc. Natl. Acad. Sci. U. S. A 101, 10626-10631 (2004).