The goal of this three-year proposal is to clarify how the insect steroid hormone 20-hydroxyecdysone (20E) interacts with cell cycle machinery in mosquito (Aedes albopictus C7-10 cells.
A first Aim i s to identify which phases of the mitotic cell cycle: G1, S, G2 or M, are affected by 20E, and whether the effect is stimulatory or inhibitory. These analyses will draw upon elegant studies with estrogen-responsive mammalian cells, in which hormone treatment predominantly affects the G1 phase of the cycle, where proteins known as the D1 cyclins relay information from the external environment to the intrinsic cell cycle machinery. Preliminary studies have shown that C7-10 cells respond to 20E: 20E-inducible proteins have been identified, and the cells express transcripts encoding the ecdysone receptor proteins EcR and USP. Available data suggest that in the presence of 20E, C7-10 mosquito cells complete the cycle in progress before the 20E response is detectable.
A second Aim i s to complete ongoing analyses of the EcR and USP isoforms expressed by these C7-10 cells and to further investigate the time course of appearance of 20E inducible proteins in the context of cell- cycle specific patterns of protein expression. The goal is to identify a component(s) of the cell cycle machinery that is involved in the early response to 20E. A third goal is to characterize a 40 kDa DNA binding protein that interacts with Drosophila DNA containing a known 20E response element. These studies will be based on an understanding of C7-10 cell cycle parameters and synchronization procedures that have been established in the PI's laboratory, as well as standard molecular biology techniques. Results of this study will provide novel insights into the effects of 20E on cell growth and proliferation, which are directly relevant to efforts to control vector-borne disease by genetic manipulation of insect vectors.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI043971-03
Application #
6328789
Study Section
Special Emphasis Panel (ZRG5-TMP (01))
Program Officer
Aultman, Kathryn S
Project Start
1998-12-01
Project End
2002-11-30
Budget Start
2000-12-01
Budget End
2002-11-30
Support Year
3
Fiscal Year
2001
Total Cost
$162,912
Indirect Cost
Name
University of Minnesota Twin Cities
Department
Zoology
Type
Schools of Earth Sciences/Natur
DUNS #
168559177
City
Minneapolis
State
MN
Country
United States
Zip Code
55455
Gerenday, Anna; Fallon, Ann M (2011) Increased levels of the cell cycle inhibitor protein, dacapo, accompany 20-hydroxyecdysone-induced G1 arrest in a mosquito cell line. Arch Insect Biochem Physiol 78:61-73
Fallon, Ann M; Gerenday, Anna (2010) Ecdysone and the cell cycle: investigations in a mosquito cell line. J Insect Physiol 56:1396-401
Ma, L; Gerenday, A; Coley, K M et al. (2006) Co-immunoprecipitation of putative proteins that interact with mosquito proliferating cell nuclear antigen. Insect Mol Biol 15:197-205
Jayachandran, G; Fallon, A M (2004) The mosquito ribonucleotide reductase R2 gene: ultraviolet light induces expression of a novel R2 variant with an internal amino acid deletion. Insect Mol Biol 13:231-9
Jayachandran, Gitanjali; Fallon, Ann M (2003) Ribosomal protein P0 from Aedes albopictus mosquito cells: cDNA cloning and analysis of expression. Genetica 119:1-10
Eccleston, E D; Gerenday, Anna; Fallon, Ann M (2002) Leveraging genomic databases: from an Aedes albopictus mosquito cell line to the malaria vector Anopheles gambiae via the Drosophila genome project. Insect Mol Biol 11:187-95
Schwientek, Melinda Sue; Higgins, LeeAnn; Fallon, Ann Marie (2002) Cultured Aedes albopictus mosquito cells accumulate elongation factor-1 alpha (EF-1 alpha) during serum starvation. Insect Biochem Mol Biol 32:1055-63
Jayachandran, G; Fallon, A M (2001) Antisense expression of the 20-hydroxyecdysone receptor (EcR) in transfected mosquito cells uncovers a new EcR isoform that varies at the C-terminal end. In Vitro Cell Dev Biol Anim 37:522-9
Jayachandran, G; Fallon, A M (2000) Evidence for expression of EcR and USP components of the 20-hydroxyecdysone receptor by a mosquito cell line. Arch Insect Biochem Physiol 43:87-96