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Translocator protein (18 kDa): an update on its function in steroidogenesis
V Papadopoulos1,2, J Fan2, B Zirkin3
1Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA.
Journal of Neuroendocrinology
|July 2, 2017
Summary
Translocator protein (TSPO) is a vital mitochondrial protein involved in cholesterol transport and steroidogenesis. Recent genetic studies in mice challenge its established role, highlighting ongoing research into its complex functions.
Area of Science:
- Mitochondrial biology
- Biochemistry
- Pharmacology
Background:
- Translocator protein (18 kDa) (TSPO) is a key mitochondrial protein.
- TSPO participates in cholesterol transport, steroidogenesis, heme synthesis, and apoptosis.
- Its role in steroidogenesis has been generally accepted until recent genetic studies.
Purpose of the Study:
- To review the structure, function, and pharmacology of TSPO.
- To discuss recent findings from genetic animal models that have created controversy.
- To evaluate TSPO as a pharmacological target for diseases involving mitochondrial activity.
Main Methods:
- Review of existing literature on TSPO structure and function.
- Analysis of data from genetic depletion studies in mice.
- Examination of TSPO's association with protein complexes in steroidogenic cells.
Main Results:
- TSPO is localized to the outer mitochondrial membrane and participates in a multiprotein complex.
- Genetic depletion studies have challenged the established role of TSPO in steroid and heme synthesis.
- TSPO stimulation shows therapeutic potential for anxiety and hypogonadism.
Conclusions:
- TSPO remains a significant mitochondrial protein with diverse functions.
- Recent genetic evidence necessitates a re-evaluation of TSPO's precise role in steroidogenesis.
- TSPO is a promising pharmacological target for conditions linked to increased mitochondrial activity.
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