STARD3/MLN64 is Striving at Membrane Contact Sites: Intracellular Cholesterol Trafficking for Steroidogenesis in Human Placental Cells
Steroid hormone synthesis begins with the conversion of cholesterol into pregnenolone by the enzyme cytochrome P450scc in mitochondria. The cholesterol used to synthesize pregnenolone is derived mainly from endocytosed LDL cholesterol. How this LDL cholesterol is transported to mitochondria in the human placenta is not well understood. Recent work has focused on how STARD3/MLN64 controls cholesterol trafficking. The STARD3 protein has a START domain that associates with cholesterol. Why STARD3 is distributed mainly to late endosomes but not to mitochondria is an obstacle to understanding the early steps in steroidogenesis. STARD3 can bind the ER protein VAP and contribute to ER-late endosome MCS formation. In this review, recent progress on STARD3 functions suggests possible models to explain how cholesterol could transit to mitochondria via MCS.
STARD3/MLN64 is Striving at Membrane Contact Sites: Intracellular Cholesterol Trafficking for Steroidogenesis in Human Placental Cells, American Journal of Life Sciences. Special Issue: Biology and Medicine of Peptide and Steroid Hormones.
Vol. 3, No. 3-2,
2015, pp. 48-52.
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