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Reverse Yeast Two-hybrid System to Identify Mammalian Nuclear Receptor Residues that Interact with Ligands and/or Antagonists
Published on: November 15, 2013
Steroid and thyroid hormone receptors in mitochondria
Anna-Maria G Psarra1, Constantine E Sekeris
1Biomedical Research Foundation, Academy of Athens, Center for Basic Research, Athens, Greece.
IUBMB Life
|March 18, 2008
Summary
Mitochondria host receptors for steroid and thyroid hormones, influencing gene transcription and cell survival. These mitochondrial receptors directly regulate mitochondrial DNA and coordinate with nuclear actions for cellular control.
Area of Science:
- Cell Biology
- Molecular Endocrinology
- Mitochondrial Biology
Background:
- Nuclear receptors for steroid and thyroid hormones are well-established regulators of cellular processes.
- Emerging evidence suggests the presence and function of these receptors within mitochondria.
Purpose of the Study:
- To investigate the presence and function of nuclear receptors within mitochondria.
- To elucidate the role of mitochondrial receptors in cellular energy production and apoptosis.
Main Methods:
- Western blotting
- Immunofluorescence labeling
- Confocal microscopy
- Immunogold electron microscopy
Main Results:
- Receptors for glucocorticoids, estrogens, androgens, and thyroid hormones were detected in mitochondria across various cell types.
- Mitochondrial receptors directly influence mitochondrial transcription and OXPHOS (oxidative phosphorylation) gene expression.
- These receptors play a role in cell survival and apoptosis through both genomic and nongenomic pathways.
Conclusions:
- Mitochondria contain a functional complement of nuclear receptors that regulate mitochondrial gene expression and cellular fate.
- Mitochondrial receptors coordinate with nuclear receptors to orchestrate cellular responses to hormonal signals.
- The discovery of nuclear receptors and transcription factors in mitochondria highlights their central role in integrating cellular signals.
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