The experiments reported in this research paper aimed to determine the effect of supplementing different forms of L-methionine (L-Met) and acetate on protein synthesis in immortalized bovine mammary epithelial cell line (MAC-T cells). Treatments were Control, L-Met, conjugated L-Met and acetate (CMA), and non-conjugated L-Met and Acetate (NMA). Protein synthesis mechanism was determined by omics method. NMA group had the highest protein content in the media and CSN2 mRNA expression levels (P< 0.05). The number of upregulated and downregulated proteins observed were 39 and 77 in L-Met group, 62 and 80 in CMA group and 50 and 81 in NMA group from 448 proteins, respectively (P< 0.05). L-Met, NMA and CMA treatments stimulated pathways related to protein and energy metabolism (P< 0.05). Metabolomic analysis also revealed that L-Met, CMA and NMA treatments resulted in increases of several metabolites (P< 0.05). In conclusion, NMA treatment increased protein concentration and expression level ofCSN2mRNA in MAC-T cells compared to control as well as L-Met and CMA treatments through increased expression of milk protein synthesis-related genes and production of the proteins and metabolites involved in energy and protein synthesis pathways.

中文翻译：

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补充缀合和非缀合的 L-蛋氨酸和乙酸盐会改变牛乳腺细胞中与蛋白质合成相关的 CSN2、蛋白质和代谢物的表达模式

本研究报告中报道的实验旨在确定补充不同形式的 L-蛋氨酸 (L-Met) 和乙酸盐对永生化牛乳腺上皮细胞系 (MAC-T 细胞) 中蛋白质合成的影响。处理是对照、L-Met、缀合的L-Met和乙酸盐(CMA)以及非缀合的L-Met和乙酸盐(NMA)。通过组学方法确定蛋白质合成机制。NMA组培养基中蛋白含量和CSN2 mRNA表达水平最高（磷< 0.05)。从 448 种蛋白质中观察到的上调和下调蛋白数量分别为 L-Met 组 39 和 77 个，CMA 组 62 和 80 个，NMA 组 50 和 81 个。磷< 0.05)。L-Met、NMA 和 CMA 处理刺激了与蛋白质和能量代谢相关的途径。磷< 0.05)。代谢组学分析还显示，L-Met、CMA 和 NMA 处理导致几种代谢物的增加（磷< 0.05)。总之，NMA处理增加了蛋白质浓度和表达水平CSN2MAC-T 细胞中的 mRNA 与对照以及 L-Met 和 CMA 处理相比，通过增加乳蛋白合成相关基因的表达和参与能量和蛋白质合成途径的蛋白质和代谢物的产生。