Estrogens are important for the maintenance of bone mineral density and the prevention of osteoporosis, a disease that affects more than 10 million people in the United States. While we have known about the importance of 17?-estradiol (E2) in bone for decades, we still do not know most of the genes regulated by E2 or how estrogen receptor 1 (ER1) regulates these genes in a tissue specific manner. The goal of this application is to further develop our functional and mechanistic understanding of how estrogen regulates genes to control osteoblast-specific function. We have identified GATA4 as a key pioneer factor for ER1. GATA4 is found at the same enhancers as ER1 in osteoblast cell lines and is required for ER1 recruitment to these enhancers. We hypothesize that GATA4 interacts with a distinct complex of proteins at ER1 binding sites to control osteoblast differentiation.
Aim 1 will determine how GATA4 controls tissue-specific transcription induced by estrogen. Finally Aim 3 will extend these studies to analyze GATA4 in vivo by creating an osteoblast-specific knockout of GATA4.
Aim 2 will determine the mechanism by which GATA4 functions in osteoblast differentiation and mineralization. Together these experiments will for the first time describe how novel osteoblast transcription factor (GATA4) regulates estrogen biology in bone.

Public Health Relevance

Osteoporosis is a significant public health concern that affects over 10 million people in the United States and, with the aging population, this number is likely to increase in the next few decades. Estrogens are important in the development of bone and maintenance of bone mineral density in mice and humans. The goal of this application is to further develop our functional and mechanistic understanding of how estrogen regulates bone cells by its interaction with another transcription factor GATA4.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
High Priority, Short Term Project Award (R56)
Project #
1R56DK090231-01
Application #
8145771
Study Section
Molecular and Cellular Endocrinology Study Section (MCE)
Program Officer
Malozowski, Saul N
Project Start
2010-09-30
Project End
2011-08-31
Budget Start
2010-09-30
Budget End
2011-08-31
Support Year
1
Fiscal Year
2010
Total Cost
$192,500
Indirect Cost
Name
University of California Los Angeles
Department
Orthopedics
Type
Schools of Medicine
DUNS #
092530369
City
Los Angeles
State
CA
Country
United States
Zip Code
90095
Güemes, Miriam; Garcia, Alejandro J; Rigueur, Diana et al. (2014) GATA4 is essential for bone mineralization via ER? and TGF?/BMP pathways. J Bone Miner Res 29:2676-87
Wend, Korinna; Wend, Peter; Drew, Brian G et al. (2013) ER? regulates lipid metabolism in bone through ATGL and perilipin. J Cell Biochem 114:1306-14
Wend, Peter; Runke, Stephanie; Wend, Korinna et al. (2013) WNT10B/?-catenin signalling induces HMGA2 and proliferation in metastatic triple-negative breast cancer. EMBO Mol Med 5:264-79
Garcia, Alejandro J; Tom, Colton; Guemes, Miriam et al. (2013) ER? signaling regulates MMP3 expression to induce FasL cleavage and osteoclast apoptosis. J Bone Miner Res 28:283-90
Wend, P; Wend, K; Krum, S A et al. (2012) The role of WNT10B in physiology and disease. Acta Physiol (Oxf) 204:34-51
Miranda-Carboni, Gustavo A; Guemes, Miriam; Bailey, Shannon et al. (2011) GATA4 regulates estrogen receptor-alpha-mediated osteoblast transcription. Mol Endocrinol 25:1126-36
Krum, Susan A (2011) Direct transcriptional targets of sex steroid hormones in bone. J Cell Biochem 112:401-8