Heme oxygenase (HO) catalyzes the oxidative cleavage of heme to biliverdin with production of CO and release of the chelated Fe3+. Although much is known about the function, multiplicity and regulation of the mammalian and algal heme oxygenase systems, practically no attention has been given to the heme oxygenases in insects. I proposed to study for the first time heme oxygenase in an invertebrate animal. The long term goal of the proposed research project is to fill a gap in our knowledge of heme metabolism in blood feeding insects. The results obtained will define the role of heme oxygenase in iron re-utilization and homeostasis in mosquitoes. They will provide a tool to study the fate of heme in hematophagous insect vectors of disease, and may lead to the design of novel and effective ways to control insects of medical importance.
The specific aims of the project are: 1. To clone and characterize HO cDNA(s) from the mosquito A. aegypti. Using D. melanogaster HO molecular probes (cDNA, antibodies) we will screen for similar HO cDNAs in A. aegypti. These will be sequenced and the structure of the deduced protein(s) will be determined. 2. To express, purify and characterize A. aegypti heme oxygenase protein(s). Using a heterologous expression system, A. aegypti heme oxygenase(s) will be partially characterized and compared to other heme oxygenases. The recombination protein will be used for production of polyclonal antibodies. 3. To determine the expression pattern of A. aegypti heme oxygenase(s) during the development, in different organs, and after blood feeding Using northern and western blotting techniques, the expression of A. aegypti HO mRNA(s) and protein(s) will be studied at different developmental stages and in female mosquitoes before and after a blood meal. The organ specific expression will be studied in larvae and in female mosquitoes at various stages before and after blood feeding.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM058918-05
Application #
6707492
Study Section
Special Emphasis Panel (ZRG1-TMP (01))
Program Officer
Ikeda, Richard A
Project Start
2000-04-01
Project End
2006-03-31
Budget Start
2004-04-01
Budget End
2006-03-31
Support Year
5
Fiscal Year
2004
Total Cost
$189,375
Indirect Cost
Name
University of Arizona
Department
Biochemistry
Type
Schools of Arts and Sciences
DUNS #
806345617
City
Tucson
State
AZ
Country
United States
Zip Code
85721
Dunkov, Boris; Georgieva, Teodora (2006) Insect iron binding proteins: insights from the genomes. Insect Biochem Mol Biol 36:300-9
Missirlis, Fanis; Holmberg, Sara; Georgieva, Teodora et al. (2006) Characterization of mitochondrial ferritin in Drosophila. Proc Natl Acad Sci U S A 103:5893-8
Paiva-Silva, Gabriela O; Cruz-Oliveira, Christine; Nakayasu, Ernesto S et al. (2006) A heme-degradation pathway in a blood-sucking insect. Proc Natl Acad Sci U S A 103:8030-5
Harizanova, N; Georgieva, T; Dunkov, B C et al. (2005) Aedes aegypti transferrin. Gene structure, expression pattern, and regulation. Insect Mol Biol 14:79-88
Georgieva, T; Dunkov, B C; Dimov, S et al. (2002) Drosophila melanogaster ferritin: cDNA encoding a light chain homologue, temporal and tissue specific expression of both subunit types. Insect Biochem Mol Biol 32:295-302
Dunkov, Boris C; Georgieva, Teodora; Yoshiga, Toyoshi et al. (2002) Aedes aegypti ferritin heavy chain homologue: feeding of iron or blood influences message levels, lengths and subunit abundance. J Insect Sci 2:7