Project description:Dysregulated Genes between miR-378 vs. negative control ovarian cancer cells We transfected ovarian cancer cell lines with miR-378 or negative control
Project description:To explore the circadian functions of the miRNAs derived from these circadian primary miRNA transcripts, we focused on miR-378 and examined the transcriptome changes in mouse livers upon miR-378 over-expression at two circadian time points, CT10 and CT22. First, we observed a significant over-representation of the circadian oscillating genes affected by miR-378 over-expression. Cell cycle genes are further enriched in the affected circadian oscillating genes, which implied that miR-378 mediates the circadian control of cell cycle. Our examination of circadian regulatory network involving miR-378 suggests that miR-378 mediates the circadian control of cell cycle and metabolism by forming either coherent or incoherent feed-forward loops with circadian TFs.
Project description:An improved mechanistic understanding of the thyroid hormone (TH) action on bile acid (BA) synthetic pathway, the major route for cholesterol elimination, will facilitate the identification of novel therapeutic targets for hypercholesterolemia. Here, we show that hepatic miR-378 is positively regulated by TH. Transient overexpression of miR-378 in the liver of mice reduces the serum cholesterol levels, which is accompanied with an upregulation of key enzymes involved in the intrahepatic conversion of cholesterol to BAs. Importantly, transgenic mice with liver-specific and moderate overexpression of miR-378 also display a decrease in serum cholesterol levels accompanied with an enhanced BA synthesis and are resistant to diet-induced hypercholesterolemia. In contrast, mice lacking miR-378 exhibit an elevation of serum cholesterol levels accompanied with an impaired BA synthesis. Mechanistic studies reveal that hepatic miR-378 regulates BA synthesis and cholesterol homeostasis through its direct target gene MAFG, which is a transcriptional repressor of BA synthetic genes. We also show that miR-378 serves as an essential component in either incoherent or coherent feed-forward loop to confer robust and precise controls on BA synthesis in response to TH signalling. Together, we identify a previously undescribed miR-378-mediated mechanism underlying the cholesterol-lowering effect of TH. Our findings not only add a new dimension to our understanding the regulation of BA synthesis by TH, but also provide new therapeutic regimens to manage serum cholesterol levels.
Project description:An improved mechanistic understanding of the thyroid hormone (TH) action on bile acid (BA) synthetic pathway, the major route for cholesterol elimination, will facilitate the identification of novel therapeutic targets for hypercholesterolemia. Here, we show that hepatic miR-378 is positively regulated by TH. Transient overexpression of miR-378 in the liver of mice reduces the serum cholesterol levels, which is accompanied with an upregulation of key enzymes involved in the intrahepatic conversion of cholesterol to BAs. Importantly, transgenic mice with liver-specific and moderate overexpression of miR-378 also display a decrease in serum cholesterol levels accompanied with an enhanced BA synthesis and are resistant to diet-induced hypercholesterolemia. In contrast, mice lacking miR-378 exhibit an elevation of serum cholesterol levels accompanied with an impaired BA synthesis. Mechanistic studies reveal that hepatic miR-378 regulates BA synthesis and cholesterol homeostasis through its direct target gene MAFG, which is a transcriptional repressor of BA synthetic genes. We also show that miR-378 serves as an essential component in either incoherent or coherent feed-forward loop to confer robust and precise controls on BA synthesis in response to TH signalling. Together, we identify a previously undescribed miR-378-mediated mechanism underlying the cholesterol-lowering effect of TH. Our findings not only add a new dimension to our understanding the regulation of BA synthesis by TH, but also provide new therapeutic regimens to manage serum cholesterol levels
Project description:The files represent mRNAseq data of the HL60 cell line (untransduced), and duplicate samples of HL60s transduced with empty (scrambled) control vector (System Biosciences, Cat. #MZIP000-VA-1) and duplicate samples of HL60s transduced with miRZip anti-miRNA Expression lentivector for miR-378-3p (System Biosciences, Cat# CS970A-1).