Grantee Research Project Results
Estrogen-Regulated Gene Expression in Largemouth Bass (Micropterus salmoides)EPA Grant Number: U915643
Title: Estrogen-Regulated Gene Expression in Largemouth Bass (Micropterus salmoides)
Investigators: Bowman, Christopher J.
Institution: University of Florida
EPA Project Officer: Fields, Nigel
Project Period: September 1, 1999 through September 1, 2001
Project Amount: $84,768
RFA: STAR Graduate Fellowships (1999)
Research Category: Academic Fellowships , Fellowship - Toxicology , Health Effects
The overall objective of this research project is to characterize differential effects on the primary and delayed-primary molecular response to different types of estrogenlike chemicals. Specifically, I would like to profile the gene induction of the estrogen receptor (ER) and vitellogenin (Vtg) to estradiol (E2), ethinylestradiol (EE2), and methoxychlor (MXC) with respect to dose and time.The hypothesis is that E2, EE2, and MXC will exhibit different characteristic transactivational primary- and delayed-primary responses because of the ligand-dependent variation on mRNA stability and half-life.Approach:
The hypothesis will be tested in vitro and in vivo. I will need to clone and sequence cDNA fragments to the ER and Vtg genes in largemouth bass (LMB). The in vitro approach encompasses the development, characterization, and validation of a LMB primary hepatocyte model. Once this tool is developed, I plan to characterize dose and time response for Vtg and ER mRNA induced by E2, EE2, and MXC. This will be followed by Vtg protein analysis. Similar experiments examining dose and time response also will be conducted in vivo to compare cell-specific responses to that as seen in the whole animal. These comparisons will be made at the mRNA level of the ER and Vtg genes, followed by Vtg protein accumulation. I also will study the transcription rates and mRNA stability of Vtg mRNAs with different chemical exposures in the primary-hepatocyte culture system.Supplemental Keywords:
fellowship, largemouth bass, LMB, estrogen receptor, ER, vitellogenin, Vtg, mRNA, primary hepatocytes.