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Protocols for Visualizing Steroidogenic Organs and Their Interactive Organs with Immunostaining in the Fruit Fly Drosophila melanogaster
Published on: April 14, 2017
Role of mitochondria in steroidogenesis
Vassilios Papadopoulos1, Walter L Miller
1The Research Institute of the McGill University Health Centre, Department of Medicine, McGill University, Montreal, Quebec H3G 1A4, Canada. vissilios.papadopoulos@mcgill.ca
Abstract:
Adrenal gonadal, placental and brain mitochondria contain several steroidogenic enzymes, notably the cholesterol side chain cleavage enzyme, P450scc, which is the enzymatic rate-limiting step in steroidogenesis which determines cellular steroidogenic capacity. Even before this step, the access of cholesterol to this enzyme system is both rate-limiting and the site of acute regulation via the steroidogenic acute regulatory protein (StAR) which interacts with a complex multi-component 'transduceosome' on the outer mitochondrial membrane (OMM). The components of the transduceosome include the 18 kDa translocator protein (TSPO), the voltage-dependent anion channel (VDAC-1), TSPO-associated protein 7 (PAP7, ACBD3 for acyl-CoA-binding-domain 3), and protein kinase A regulatory subunit 1α (PKAR1A). The precise fashion in which these proteins interact and move cholesterol from the OMM to P450scc, and the means by which cholesterol is loaded into the OMM, remain unclear. Human deficiency diseases have been described for StAR and for P450scc. Mitochondria also contain several 'downstream' steroidogenic enzymes.
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