摘要
The present study aimed to comparatively characterize the ruminal epithelial protein expression profiles in lambs fed ewe milk or milk plus starter diet using proteome analysis. Twenty new-born lambs were randomly divided into a group receiving ewe milk (M, n = 10) and a group receiving milk plus starter diet (M + S, n = 10). From 10 d old, M group lambs remained with the ewe and suckled ewe milk without receiving the starter diet. The lambs in the M + S group were separated from the ewe and received starter feed. All lambs were slaughtered at 56 d old. Eight rumen epithelia samples (4 per group) were collected to characterize their protein expression profiles using proteomic technology. Proteome analysis showed that 31 upregulated proteins and 40 downregulated proteins were identified in the rumen epithelium of lambs in response to starter diet supplementation. The results showed that starter feeding regulates a variety of biological processes in the epithelium, especially blood vessel development and extracellular matrix protein expression. Meanwhile, the expression of proteins associated with synthesis and degradation of ketone bodies, butanoate metabolism, and citrate cycle signaling transduction pathway were upregulated in the group with starter diet supplementation, including 3-hydroxy-3-methylglutaryl coenzyme A synthase (HMGCS2, fold change [FC] = 1.93), 3-hydroxybutyrate dehydrogenase 1 (BDH1, FC = 1.91), and isocitrate dehydrogenase 1 (IDH1, FC = 8.12). The metabolic processes associated with ammonia detoxification and antioxidant stress were also affected by starter diet supplementation, with proteins, microsomal glutathione S-transferase 3 (MGST3, FC = 2.37) and IDH1, linked to the biosynthesis of glutamate and glutathione metabolism pathway being upregulated in the group with starter diet supplementation. In addition, starter feeding decreased the expression of Ras-related protein rap-1A (RAP1A, FC = 0.48) enriched in Rap1 signaling pathway, Ras signaling pathway, cyclic adenosine monophosphate (cAMP) signaling pathway, and mitogen-activated protein kinase (MAPK) signaling pathway. In summary, starter feed supplementation changed the expression of proteins related to energy production, ammonia detoxification, antioxidant stress, and signaling pathways related to proliferation and apoptosis, which facilitates the rumen epithelia development in lambs. The results provide new insights into the molecular adaptation of rumen epithelia in response to starter diet supplementation at the protein level in lambs.
摘要译文
本研究旨在使用蛋白酶组分析比较表征羔羊喂养eWE牛奶或牛奶加启动饮食中的脊髓上皮蛋白表达谱。将二十个新出生的羊羔随机分为接受eWE牛奶（M，N = 10）的基团和接受牛奶加启动饮食（M + S，N = 10）。从10 d旧的，M组羊羔留在母羊和母牛牛奶，而不接受起始饮食。将M + S基团中的羊羔与eWE分离并接受起始进料。所有的羊羔都在56 d旧的屠宰。收集八个瘤胃上皮样品（每组4个）以使用蛋白质组学技术表征其蛋白质表达谱。蛋白质组分析表明，在羔羊的瘤胃上皮中鉴定了31种上调的蛋白质和40个下调蛋白，响应于起始饮食补充剂。结果表明，起始进料调节上皮内的各种生物过程，尤其是血管发育和细胞外基质表达。同时，在具有起始饮食补充的基团中，上调了与酮体，丁酮代谢和柠檬酸盐循环信号转导途径的合成和降解相关的蛋白质的表达，包括3-羟基-3-甲基谷辅酶A合成酶（HMGCS2，折叠变化[Fc] = 1.93），3-羟基丁酸酯脱氢酶1（BDH1，Fc = 1.91），和异柠檬酸脱氢酶1（IDH1，Fc = 8.12）。与氨解毒和抗氧化胁迫相关的代谢过程也受起动饮食补充的影响，用蛋白质，微粒体谷胱甘肽S-转移酶3（Mgst3，Fc = 2.37）和IdH1，与谷氨酸的生物合成和谷胱甘肽的生物合成途径相连，并在上调该组与起始饮食补充。此外，起始进料降低了RAS相关蛋白RAM-1A（RAP1A，FC = 0.48）的表达，富含RAP1信号通路，RAS信号通路，环状腺苷一磷酸盐（CAMP）信号通路和丝裂原激活蛋白激酶（MAPK ）信号通路。总之，起始饲料补充改变了与能量产量，氨解毒，抗氧化应激和与增殖和凋亡相关的信号通路相关的蛋白质的表达，这促进了羔羊中瘤胃上皮发育。结果对瘤胃上皮的分子适应响应于乳绒蛋白水平的蛋白质水平的分子适应来提供新的见解。
Daming Sun[a][b][c];Shengyong Mao[a][b][c];Weiyun Zhu[a][b][c];Junhua Liu[a][b][c]. Proteomic identification of ruminal epithelial protein expression profiles in response to starter feed supplementation in pre-weaned lambs[J]. Animal Nutrition, 2021,7(4): 1271-1282