MicroRNA-24 can control triacylglycerol synthesis in goat mammary epithelial cells by targeting the fatty acid synthase gene

J Dairy Sci. 2015 Dec;98(12):9001-14. doi: 10.3168/jds.2015-9418. Epub 2015 Oct 23.

Abstract

In nonruminants it has been demonstrated that microRNA-24 (miR-24) is involved in preadipocyte differentiation, hepatic lipid, and plasma triacylglycerol synthesis. However, its role in ruminant mammary gland remains unclear. In this study we measured miR-24 expression in goat mammary gland tissue at 4 different stages of lactation and observed that it had highest expression at peak lactation when compared with the dry period. Overexpression or downregulation of miR-24 in goat mammary epithelial cells (GMEC) strongly affected fatty acid profiles; in particular, miR-24 enhanced unsaturated fatty acid concentration. Additional effects of miR-24 included changes in triacylglycerol content and the expression of fatty acid synthase, sterol regulatory element binding transcription protein 1, stearoyl-CoA desaturase, glycerol-3-phosphate acyltransferase mitochondrial, and acetyl-CoA carboxylase. Luciferase reporter assay confirmed that fatty acid synthase is a target of miR-24. Taken together, these results not only highlight the physiological importance of miR-24 in fatty acid metabolism in GMEC, but also laid the foundation for further research on regulatory mechanisms among miR-24 and other microRNA expressed in GMEC.

Keywords: fatty acid synthase; microRNA-24; milk fat metabolism.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetyl-CoA Carboxylase / genetics
  • Acetyl-CoA Carboxylase / metabolism
  • Amino Acid Sequence
  • Animals
  • Cells, Cultured
  • Down-Regulation
  • Epithelial Cells / metabolism*
  • Fatty Acid Synthases / genetics*
  • Fatty Acid Synthases / metabolism
  • Female
  • Glycerol-3-Phosphate O-Acyltransferase / genetics
  • Glycerol-3-Phosphate O-Acyltransferase / metabolism
  • Goats
  • Lactation
  • Lipid Metabolism
  • Mammary Glands, Animal / metabolism*
  • MicroRNAs / genetics*
  • MicroRNAs / metabolism
  • Molecular Sequence Data
  • Stearoyl-CoA Desaturase / genetics
  • Stearoyl-CoA Desaturase / metabolism
  • Sterol Regulatory Element Binding Protein 1 / genetics
  • Sterol Regulatory Element Binding Protein 1 / metabolism
  • Triglycerides / biosynthesis*

Substances

  • MicroRNAs
  • Sterol Regulatory Element Binding Protein 1
  • Triglycerides
  • Stearoyl-CoA Desaturase
  • Glycerol-3-Phosphate O-Acyltransferase
  • Fatty Acid Synthases
  • Acetyl-CoA Carboxylase