The mTOR Signaling Pathway Regulating Milk Protein Synthesis in Mammary Epithelial Cells of Dairy Cows (Bos taurus)
YANG Song-Hua, DU Rui-Fang, GAO Yuan-Da, LI Fei, GUO Long*
College of Pastoral Agriculture Science and Technology/State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, Lanzhou 730000, China
Abstract：Mammalian target of rapamycin (mTOR) is an evolutionarily conserved serine/threonine protein kinase with important regulatory roles in cell growth and many biosynthetic and catabolic processes, especially in mammary casein synthesis. mTOR signaling pathway plays a key role in determining milk yield and quality. Amino acids can be used as signaling molecules to promote the phosphorylation of the mTOR signaling pathway and regulate the synthesis of milk proteins in mammary epithelial cells of dairy cows (Bos taurus). This paper focuses on the structure and function of the mTOR signaling pathway in mammary cells, and reveals the amino acid sensing system of mTOR signaling in the regulation of milk protein synthesis in the light of the progress of related research, with a view to providing reference for further optimizing the amino acid nutrition of dairy cows, improving the efficiency of amino acid utilization, and then improving the yield and quality of cow milk.
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