Research Progress on the Key Transcription Factors Regulating Mammary Fatty Acid Metabolism in Ruminants
XIN Hui-Jie1, LIU Jian-Xin2, SHI Heng-Bo2,*
1 College of Life Science and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, China; 2 Institute of Dairy Science, College of Animal Science, Zhejiang University, Hangzhou 310058, China
Abstract：Milk fat is an important evaluation index for milk quality. In addition to serving as an energy source, milk fat plays an important physiological role in human health. Mammary fatty acid metabolism in ruminants is regulated by nuclear transcription factors. In recent years, the regulation of nuclear transcription factors in ruminant mammary fatty acid metabolism has made important progress. A decisive role of ligand-dependent transcription factors including peroxisome proliferator-activated receptor family (PPAR), liver X receptor (LXR) in regulating mammary fatty acid metabolism was confirmed. Both PPAR and LXR can form transcriptional complexes that bind to the promoter of downstream target genes, thereby affecting the activity of pathways related to milk fat metabolism. The physiological functions of different gene subtypes of PPAR and LXR are varied. Sterol regulatory element-binding protein 1 (SREBP1), regulating de novo fatty acid synthesis, is a classical transcription factor regulating mammary fatty acid synthesis. In this paper, the recent advances in mammary fatty acid synthesis regulated by key transcription factors were reviewed, which will provide references for the regulation of milk fat synthesis.
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