1. A regulatory role for microRNA 33* in controlling lipid metabolism gene expression.
- Author
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Goedeke L, Vales-Lara FM, Fenstermaker M, Cirera-Salinas D, Chamorro-Jorganes A, Ramírez CM, Mattison JA, de Cabo R, Suárez Y, and Fernández-Hernando C
- Subjects
- 3' Untranslated Regions, Animals, Base Sequence, Cell Line, Conserved Sequence, Fatty Acids metabolism, Humans, Liver cytology, Liver physiology, Macaca mulatta genetics, Macrophages cytology, Macrophages physiology, Male, Mice, Mice, Inbred C57BL, MicroRNAs metabolism, Gene Expression Regulation, Lipid Metabolism genetics, MicroRNAs genetics
- Abstract
hsa-miR-33a and hsa-miR-33b, intronic microRNAs (miRNAs) located within the sterol regulatory element-binding protein 2 and 1 genes (Srebp-2 and -1), respectively, have recently been shown to regulate lipid homeostasis in concert with their host genes. Although the functional role of miR-33a and -b has been highly investigated, the role of their passenger strands, miR-33a* and -b*, remains unclear. Here, we demonstrate that miR-33a* and -b* accumulate to steady-state levels in human, mouse, and nonhuman primate tissues and share a similar lipid metabolism target gene network as their sister strands. Analogous to miR-33, miR-33* represses key enzymes involved in cholesterol efflux (ABCA1 and NPC1), fatty acid metabolism (CROT and CPT1a), and insulin signaling (IRS2). Moreover, miR-33* also targets key transcriptional regulators of lipid metabolism, including SRC1, SRC3, NFYC, and RIP140. Importantly, inhibition of either miR-33 or miR-33* rescues target gene expression in cells overexpressing pre-miR-33. Consistent with this, overexpression of miR-33* reduces fatty acid oxidation in human hepatic cells. Altogether, these data support a regulatory role for the miRNA* species and suggest that miR-33 regulates lipid metabolism through both arms of the miR-33/miR-33* duplex.
- Published
- 2013
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