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Updated: Jul 16, 2026
10:36
Systems Biology of Metabolic Regulation by Estrogen Receptor Signaling in Breast Cancer
Published on: March 17, 2016
Mitochondrial estrogen receptors--new insights into specific functions
1Johns Hopkins University, Bloomberg School of Public Health, Baltimore, MD 21205, USA. jyager@jhsph.edu
Trends in Endocrinology and Metabolism: TEM
|February 28, 2007
Summary
Estrogen receptors (ERs) in mitochondria and cell membranes inhibit apoptosis via distinct pathways. Mitochondrial ER signaling activates manganese superoxide dismutase, crucial for cell survival.
Area of Science:
- Cell Biology
- Endocrinology
- Molecular Biology
Background:
- Estrogen receptors (ERs) are known to exist in cellular membranes and the nucleus.
- The presence and function of ER alpha and ERbeta within mitochondria are less understood.
- Estrogen signaling influences cellular processes, including apoptosis, but the specific roles of mitochondrial ERs remain unclear.
Purpose of the Study:
- To investigate the role of mitochondrial estrogen receptors (ERs) in cellular responses to 17beta-estradiol.
- To elucidate the signaling pathways mediated by membrane and mitochondrial ERs in the inhibition of apoptosis.
- To determine the specific mechanisms by which mitochondrial ERs contribute to cell survival.
Main Methods:
- Investigating estrogen receptor localization in cellular membranes and mitochondria.
- Analyzing the effects of 17beta-estradiol on apoptosis.
- Mapping signaling pathways involving protein kinases and manganese superoxide dismutase.
Main Results:
- Estrogen receptor alpha and ERbeta are confirmed to be present in mitochondria.
- 17beta-estradiol inhibits early apoptosis through both membrane and mitochondrial ER signaling.
- Mitochondrial ER signaling directly or indirectly activates manganese superoxide dismutase, contributing to apoptosis inhibition.
Conclusions:
- Mitochondrial ERs play a significant role in estrogen-mediated cellular responses, particularly in preventing apoptosis.
- Distinct signaling pathways are utilized by membrane ERs (protein kinases) and mitochondrial ERs (manganese superoxide dismutase activation).
- Mitochondrial ER signaling is a key component in the cytoprotective effects of estrogen.
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