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Translocator protein/peripheral benzodiazepine receptor is not required for steroid hormone biosynthesis.

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TLDR
The results show that TSPO function is not essential for steroid hormone biosynthesis and challenge the prevailing dogma that claims an essential role for T SPO in steroid hormone synthesis and force reexamination of functional interpretations made for this protein.
Abstract
Molecular events that regulate cellular biosynthesis of steroid hormones have been a topic of intense research for more than half a century. It has been established that transport of cholesterol into the mitochondria forms the rate-limiting step in steroid hormone production. In current models, both the steroidogenic acute regulatory protein (StAR) and the translocator protein (TSPO) have been implicated to have a concerted and indispensable effort in this cholesterol transport. Deletion of StAR in mice resulted in a critical failure of steroid hormone production, but deletion of TSPO in mice was found to be embryonic lethal. As a result, the role of TSPO in cholesterol transport has been established only using pharmacologic and genetic tools in vitro. To allow us to explore in more detail the function of TSPO in cell type-specific experimental manipulations in vivo, we generated mice carrying TSPO floxed alleles (TSPOfl/fl). In this study we made conditional knockout mice (TSPOcΔ/Δ) with TSPO deletion in testicular Leydig cells by crossing with an anti-Mullerian hormone receptor type II cre/+ mouse line. Genetic ablation of TSPO in steroidogenic Leydig cells in mice did not affect testosterone production, gametogenesis, and reproduction. Expression of StAR, cytochrome P450 side chain cleavage enzyme, 3β-hydroxysteroid dehydrogenase/Δ5-Δ4 isomerase type I, and TSPO2 in TSPOcΔ/Δ testis was unaffected. These results challenge the prevailing dogma that claims an essential role for TSPO in steroid hormone biosynthesis and force reexamination of functional interpretations made for this protein. This is the first study examining conditional TSPO gene deletion in mice. The results show that TSPO function is not essential for steroid hormone biosynthesis.

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The Next Generation of Platinum Drugs: Targeted Pt(II) Agents, Nanoparticle Delivery, and Pt(IV) Prodrugs

TL;DR: Recently, there has been a surge of activity, based on a great deal of mechanistic information, aimed at developing nonclassical platinum complexes that operate via mechanisms of action distinct from those of the approved drugs as mentioned in this paper.
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The Mitochondrial Permeability Transition Pore: Channel Formation by F-ATP Synthase, Integration in Signal Transduction, and Role in Pathophysiology

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Glutathione and mitochondria.

TL;DR: As mitochondria play a central strategic role in the activation and mode of cell death, mitochondrial GSH has been shown to critically regulate the level of sensitization to secondary hits that induce mitochondrial membrane permeabilization and release of proteins confined in the intermembrane space that once in the cytosol engage the molecular machinery of cellDeath.
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Leydig cells: formation, function, and regulation.

TL;DR: With knowledge gained of the mechanisms involved in testosterone formation, it is also conceivable to use pharmacological means to increase serum testosterone by Leydig cell stimulation.
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Microglial Activation in Traumatic Brain Injury

TL;DR: The role of microglia in TBI is reviewed, analyzing their distribution, morphology and functional phenotype over time in animal models and in humans, and some novel potential therapeutic approaches that prime microglian/macrophages toward the beneficial restorative microglial phenotype after TBI are outlined.
References
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Journal ArticleDOI

Analysis of relative gene expression data using real-time quantitative pcr and the 2(-delta delta c(t)) method

TL;DR: The 2-Delta Delta C(T) method as mentioned in this paper was proposed to analyze the relative changes in gene expression from real-time quantitative PCR experiments, and it has been shown to be useful in the analysis of realtime, quantitative PCR data.
Journal ArticleDOI

A robust and high-throughput Cre reporting and characterization system for the whole mouse brain

TL;DR: A set of Cre reporter mice with strong, ubiquitous expression of fluorescent proteins of different spectra is generated and enables direct visualization of fine dendritic structures and axonal projections of the labeled neurons, which is useful in mapping neuronal circuitry, imaging and tracking specific cell populations in vivo.
Journal ArticleDOI

Specific benzodiazepine receptors in rat brain characterized by high-affinity (3H)diazepam binding

TL;DR: Specific [3H]diazepam binding to membranes appears to be restricted to brain, where it is unevenly distributed: the density of diazepam receptors is about five times higher in cortex (the highest density) than in pons-meddula (lowest density).
Journal ArticleDOI

The purification, cloning, and expression of a novel luteinizing hormone-induced mitochondrial protein in MA-10 mouse Leydig tumor cells. Characterization of the steroidogenic acute regulatory protein (StAR).

TL;DR: It is demonstrated for the first time that expression of the protein in MA-10 cells in the absence of hormone stimulation is sufficient to induce steroid production and it is proposed that this protein is required in the acute regulation of steroidogenesis.
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