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Updated: May 24, 2026
12:05
Production of Disulfide-stabilized Transmembrane Peptide Complexes for Structural Studies
Published on: March 6, 2013
Structural and functional evolution of the translocator protein (18 kDa)
J Fan1, P Lindemann, M G J Feuilloley
1Research Institute of the McGill University Health Centre, Montreal, Quebec H3G 1A4, Canada.
Current Molecular Medicine
|February 28, 2012
Summary
Translocator protein (TSPO) genes are ancient and found across life. A newly identified TSPO paralog suggests specialized roles in metabolism and mitochondrial function, expanding our understanding of this conserved protein family.
Area of Science:
- Biochemistry
- Evolutionary Biology
- Cellular Biology
Background:
- Translocator proteins (TSPO) are evolutionarily conserved proteins found in various organisms, from bacteria to humans.
- Human TSPO is crucial for cholesterol transport into mitochondria, a key step in steroidogenesis, and is upregulated in cancer and injury.
- The hypothesis suggests TSPO plays roles in apoptosis and mitochondrial integrity.
Purpose of the Study:
- To review the evolutionary origins of Tspo genes across different domains of life (Bacteria, Archaea, Eukarya).
- To provide a comprehensive overview of the divergent functions of the TSPO gene family.
- To highlight the specialized functions of a newly identified TSPO paralog.
Main Methods:
- Literature review of existing studies on TSPO homologs in mammals, bacteria, and plants.
- Analysis of evolutionary gene duplication events leading to TSPO paralogs.
- Examination of tissue-, cell-, and organelle-specific functions of TSPO family members.
Main Results:
- TSPO family members regulate specialized functions related to oxygen-mediated metabolism.
- A novel TSPO paralog, identified in humans and mice, arose from an ancient gene duplication.
- This paralog exhibits specialized tissue-, cell-, and organelle-specific functions.
Conclusions:
- The TSPO gene family has a deep evolutionary history and diverse functional roles.
- The discovery of a new paralog underscores the specialized functions within the TSPO family.
- TSPO proteins are integral to oxygen-mediated metabolic processes across diverse life forms.
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