{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T23:46:54Z","timestamp":1783036014121,"version":"3.54.6"},"reference-count":42,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,4,27]],"date-time":"2026-04-27T00:00:00Z","timestamp":1777248000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100009110","name":"Natural Science Foundation of Xinjiang Uygur Autonomous Region","doi-asserted-by":"publisher","award":["2022D01D10"],"award-info":[{"award-number":["2022D01D10"]}],"id":[{"id":"10.13039\/100009110","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["CIMB"],"abstract":"<jats:p>Amino acids play a dual role in milk protein synthesis, functioning as both metabolic precursors and signaling molecules. This study aimed to elucidate the molecular mechanism by which glycine regulates \u03b1-casein production in bovine mammary epithelial cells (MAC-T). Under serum-free conditions, MAC-T cells were exposed to graded concentrations of glycine (1.105, 2.209, 4.418, 8.836, 17.673, and 35.345 mM) for 24 h. \u03b1-Casein levels in cell lysates and culture supernatants were quantified by ELISA. Transcriptional activity of casein-encoding genes (CSN1S1, CSN1S2) and PI3K-AKT-mTOR pathway components was assessed by RT-qPCR. Phosphorylation status of pathway proteins was analyzed by Western blot. The functional involvement of the PI3K-AKT-mTOR pathway was validated using the specific inhibitor LY294002. Glycine stimulated \u03b1-casein synthesis and secretion in a concentration-dependent manner, with maximal efficacy at 4.418 mM. At this concentration, glycine upregulated CSN1S1, CSN1S2, and PI3K-AKT-mTOR pathway gene expression, and enhanced phosphorylation of the corresponding proteins. Inhibition of PI3K-AKT-mTOR signaling by LY294002 abolished glycine-induced \u03b1-casein synthesis, and this effect was reversed by glycine co-treatment. These findings demonstrate that glycine enhances \u03b1-casein synthesis through activation of the PI3K-AKT-mTOR pathway.<\/jats:p>","DOI":"10.3390\/cimb48050453","type":"journal-article","created":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T15:09:33Z","timestamp":1777388973000},"page":"453","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Mechanistic Insights into Glycine\u2019s Regulation of Milk Protein Synthesis via PI3K-AKT-mTOR Signaling"],"prefix":"10.3390","volume":"48","author":[{"given":"Xinyu","family":"Zhang","sequence":"first","affiliation":[{"name":"Xinjiang Key Laboratory of Meat and Milk Production Herbivore Nutrition, College of Animal Science, Xinjiang Agricultural University, Urumqi 830052, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu","family":"Ding","sequence":"additional","affiliation":[{"name":"Xinjiang Key Laboratory of Meat and Milk Production Herbivore Nutrition, College of Animal Science, Xinjiang Agricultural University, Urumqi 830052, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Min","family":"Yang","sequence":"additional","affiliation":[{"name":"Xinjiang Key Laboratory of Meat and Milk Production Herbivore Nutrition, College of Animal Science, Xinjiang Agricultural University, Urumqi 830052, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuxin","family":"Zhou","sequence":"additional","affiliation":[{"name":"Xinjiang Key Laboratory of Meat and Milk Production Herbivore Nutrition, College of Animal Science, Xinjiang Agricultural University, Urumqi 830052, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruoshan","family":"Luo","sequence":"additional","affiliation":[{"name":"Xinjiang Key Laboratory of Meat and Milk Production Herbivore Nutrition, College of Animal Science, Xinjiang Agricultural University, Urumqi 830052, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yang","family":"Yang","sequence":"additional","affiliation":[{"name":"Xinjiang Key Laboratory of Meat and Milk Production Herbivore Nutrition, College of Animal Science, Xinjiang Agricultural University, Urumqi 830052, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hang","family":"Zhang","sequence":"additional","affiliation":[{"name":"Xinjiang Key Laboratory of Meat and Milk Production Herbivore Nutrition, College of Animal Science, Xinjiang Agricultural University, Urumqi 830052, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wanping","family":"Ren","sequence":"additional","affiliation":[{"name":"Xinjiang Key Laboratory of Meat and Milk Production Herbivore Nutrition, College of Animal Science, Xinjiang Agricultural University, Urumqi 830052, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liang","family":"Yang","sequence":"additional","affiliation":[{"name":"Xinjiang Key Laboratory of Meat and Milk Production Herbivore Nutrition, College of Animal Science, Xinjiang Agricultural University, Urumqi 830052, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yong","family":"Wei","sequence":"additional","affiliation":[{"name":"Xinjiang Key Laboratory of Meat and Milk Production Herbivore Nutrition, College of Animal Science, Xinjiang Agricultural University, Urumqi 830052, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yankun","family":"Zhao","sequence":"additional","affiliation":[{"name":"Agricultural Products Quality and Safety Risk Assessment Laboratory of the Ministry of Agriculture and Rural Affairs (Urumqi) and the Xinjiang Agricultural Products Quality and Safety Laboratory, Xinjiang Academy of Agricultural Sciences, Institute of Agricultural Quality Standards and Testing Technology, Urumqi 830052, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tongjun","family":"Guo","sequence":"additional","affiliation":[{"name":"Feed Research Institute, Xinjiang Uygur Autonomous Region Academy of Animal Husbandry Sciences, Urumqi 830052, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei","family":"Shao","sequence":"additional","affiliation":[{"name":"Xinjiang Key Laboratory of Meat and Milk Production Herbivore Nutrition, College of Animal Science, Xinjiang Agricultural University, Urumqi 830052, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e14424","DOI":"10.1111\/jfbc.14424","article-title":"Potential allergenicity and hydrolysis assessment of bovine casein and \u03b2-casein by treatment with lactic acid bacteria","volume":"46","author":"Huang","year":"2022","journal-title":"J. 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