The long term goals of my research program are to find novel functions for both estrogens and estrogen response proteins, and then to identify the molecular mechanisms mediating these functions. This research will lead to a better understanding of estrogens' developmental, physiological, and biochemical roles in humans, and additionally will add to our general understanding of how estrogenic chemicals in the environment can impinge upon women's health. To pursue these research goals, we 'knocked out' the estrogen receptor (ER) gene in mice via homologous recombination and asked the following question: Would an ER- minus mouse, which lacked the classic full length ER protein, respond to any known estrogen, estrogen metabolite, or exogenous (natural or synthetic) estrogen analog? If ER-minus mice did respond, then we would know that at least one estrogen response protein other than ER exists. The working hypothesis was that several non-ER response proteins exist and that in transgenic ER-minus mice we would see a response to some estrogens, such as the environmental estrogen, methoxychlor. We have found in ER-minus mice a uterine lactoferrin mRNA response to methoxychlor and kepone, but not to estradiol. We propose that the putative methoxychlor receptor will elicit additional responses distinct from estradiol and the classic ER protein. We now hypothesize that: A) methoxychlor and other biologically important estrogens work, at least in part, through their own unique non-classical, estrogen response (NCER) proteins; and B) NCER """"""""receptors"""""""" can be readily characterized in the ER-minus mouse background. Using this mouse model system we propose to characterize the methoxychlor response and the putative methoxychlor receptor. Specifically, we propose to:
Aim #1 : Characterize lactoferrin mRNA responses to methoxychlor, kepone, and o7p'DDT in ER-minus mice;
Aim #2 : Characterize the putative methoxychlor receptor in uteri from ER-minus mice;
and Aim #3 : Compare the specificity of the responses to methoxychlor with those of estradiol, kepone, and o7p'DDT in ER-minus mice.Characterization of the putative methoxychlor, an important environmental endocrine disrupter.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Research Project (R01)
Project #
5R01ES008272-03
Application #
2749698
Study Section
Special Emphasis Panel (ZES1-CKS-B (M1))
Program Officer
Heindel, Jerrold
Project Start
1996-08-01
Project End
2000-07-31
Budget Start
1998-08-01
Budget End
2000-07-31
Support Year
3
Fiscal Year
1998
Total Cost
Indirect Cost
Name
University of Missouri-Columbia
Department
Biochemistry
Type
Schools of Medicine
DUNS #
112205955
City
Columbia
State
MO
Country
United States
Zip Code
65211
Philips, Brian J; Ansell, Pete J; Newton, Leslie G et al. (2004) Estrogen receptor-independent catechol estrogen binding activity: protein binding studies in wild-type, Estrogen receptor-alpha KO, and aromatase KO mice tissues. Biochemistry 43:6698-708
Ansell, P J; Espinosa-Nicholas, C; Curran, E M et al. (2004) In vitro and in vivo regulation of antioxidant response element-dependent gene expression by estrogens. Endocrinology 145:311-7
Day, J K; Besch-Williford, C; McMann, T R et al. (2001) Dietary genistein increased DMBA-induced mammary adenocarcinoma in wild-type, but not ER alpha KO, mice. Nutr Cancer 39:226-32
Cooke, P S; Heine, P A; Taylor, J A et al. (2001) The role of estrogen and estrogen receptor-alpha in male adipose tissue. Mol Cell Endocrinol 178:147-54
Rosenfeld, C S; Wagner, J S; Roberts, R M et al. (2001) Intraovarian actions of oestrogen. Reproduction 122:215-26
Rosenfeld, C S; Roberts, R M; Lubahn, D B (2001) Estrogen receptor- and aromatase-deficient mice provide insight into the roles of estrogen within the ovary and uterus. Mol Reprod Dev 59:336-46
Yellayi, S; Teuscher, C; Woods, J A et al. (2000) Normal development of thymus in male and female mice requires estrogen/estrogen receptor-alpha signaling pathway. Endocrine 12:207-13
Rosenfeld, C S; Cooke, P S; Welsh Jr, T H et al. (2000) The differential fate of mesonephric tubular-derived efferent ductules in estrogen receptor-alpha knockout versus wild-type female mice. Endocrinology 141:3792-8
Heine, P A; Taylor, J A; Iwamoto, G A et al. (2000) Increased adipose tissue in male and female estrogen receptor-alpha knockout mice. Proc Natl Acad Sci U S A 97:12729-34
Ghosh, D; Taylor, J A; Green, J A et al. (1999) Methoxychlor stimulates estrogen-responsive messenger ribonucleic acids in mouse uterus through a non-estrogen receptor (non-ER) alpha and non-ER beta mechanism. Endocrinology 140:3526-33

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