Transcriptome Of Bovine Mammary Gland Epithelial Cells Responding To Strearic Acid

The objective of this study was to define whether the addition of stearic acid would alter the transciptome and gene networks related to milk component synthesis in dairy bovine mammary epithelial cells (DBMEC). The expression data of encoding genes related to milk synthesis was coupled with measurements of lactose, triacylglycerol, milk protein, and fatty acid composition first. The results revealed that stearic acid not only impacts lipogenic gene networks but also affects glucose utilization, lactose synthesis, milk protein transcription/translation via the regulation of PPARG, SREBF1, JAK2, and mTOR. Data from this and previous studies were used to develop a gene network and underscore the changes induced by stearic acid.The objective of subsequent study was to identify and characterize the microRNAs (miRNAs) expressed in MEC. After bioinformatics analysis, a total of9,428,122reads belonged to miRNAs was obtained. Further analysis revealed that bta-mir-184had the most abundant expression among all388known miRNAs; while,38loci with novel hairpins were identified as novel miRNAs. Bta-U21was tissue specific and seven novel miRNAs, including bta-U21, had tissue-restricted distribution.In the end, a customized microarray containing672bovine miRNA was used to investigate their functional roles in BMEC in response to supplemental SA. Total miRNA expressed in the control and SA incubations was157and165. Seventeen of165miRNA were differentially expressed with SA, and12were verified by real-time PCR. Functional analyses revealed that gene targets of miRNAs affected by SA are associated with regulation of transcription and mTOR signaling. In parallel with the previous transcriptome study, the data on miRNAs contributes to the understanding of the functional changes induced by SA that lead to alterations in milk component synthesis.