title: MiR-27a suppresses triglyceride accumulation and affects gene mRNA expression associated with fat metabolism in dairy goat mammary gland epithelial cells.
abstract: MicroRNAs (miRNAs), a well-defined group of small RNAs containing about 22 nucleotides, participate in various biological metabolic processes. miR-27a is a miRNA that is known to regulate fat synthesis and differentiation in preadipocyte cells. However, little is known regarding the role that miR-27a plays in regulating goat milk fat synthesis. In this study, we determined the miR-27a expression profile in goat mammary gland and found that miR-27a expression was correlated with the lactation cycle. Additionally, prolactin promoted miR-27a expression in goat mammary gland epithelial cells. Further functional analysis showed that over-expression of miR-27a down-regulated triglyceride accumulation and decreased the ratio of unsaturated/saturated fatty acid in mammary gland epithelial cells. miR-27a also significantly affected mRNA expression related to milk fat metabolism. Specifically, over-expression of miR-27a reduced gene mRNA expression associated with triglyceride synthesis by suppressing PPARγ protein levels. This study provides the first experimental evidence that miR-27a regulates triglyceride synthesis in goat mammary gland epithelial cells and improves our understanding about the importance of miRNAs in milk fat synthesis.
authors.affiliation: Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Xian-Zi
authors.initials: XZ
authors.lastname: Lin
authors.forename: Jun
authors.initials: J
authors.lastname: Luo
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Heng-Bo
authors.initials: HB
authors.lastname: Shi
authors.forename: Jiang-Jiang
authors.initials: JJ
authors.lastname: Zhu
mesh_terms: D000818:Animals; D004847:Epithelial Cells / Q000378:metabolism / Q000502:physiology*; D005227:Fatty Acids / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation; D006041:Goats / Q000235:genetics* / Q000378:metabolism*; D050356:Lipid Metabolism / Q000235:genetics; D008321:Mammary Glands, Animal / Q000166:cytology* / Q000502:physiology; D035683:MicroRNAs / Q000235:genetics*; D008892:Milk / Q000737:chemistry / Q000378:metabolism; D011388:Prolactin / Q000378:metabolism; D012333:RNA, Messenger; D014280:Triglycerides / Q000235:genetics / Q000378:metabolism*
chemical_list: D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated; D035683:MicroRNAs; D012333:RNA, Messenger; D014280:Triglycerides; D011388:Prolactin