基于iTRAQ技术分析牛初乳与常乳乳清差异蛋白质组

Analysis of Differential Whey Proteome between Bovine Colostrum and Mature Milk Using Isobaric Tags for Relative and Absolute Quantitation Technology

为阐明牛初乳、牛常乳乳清蛋白的差异,利用同位素标记相对和绝对定量(isobaric tags for relative and absolute quantitation,iTRAQ)蛋白质组学技术对二者进行蛋白质组差异分析,在得到的599种具有定量信息的乳清蛋白中,鉴定出60种差异蛋白。将牛初乳与牛常乳乳清丰度差异蛋白进行生物信息学分析发现,差异蛋白主要参与的生物过程为转运、定位、单一生物作用等;主要参与的分子功能为顶端质膜、细胞外区域、细胞外区域部分等;主要参与的细胞组成为蛋白结合和阴离子结合。丰度差异蛋白中有9种是与信号传导相关,有6种糖基化乳清蛋白。此外,利用蛋白质网络互作分析发现,差异蛋白中存在具有高连接度的关键乳清蛋白因子。本研究采用iTRAO技术对牛初乳与牛常乳乳清差异蛋白进行鉴定及生物信息学分析,为今后改善牛初、常乳品质,开发婴幼儿乳粉以及功能性乳制品提供了一定参考。

In order to elucidate the differentially expressed whey proteins between bovine colostrum and mature milk, isobaric tags for relative and absolute quantitation(iTRAQ) technique was used for proteomic analysis of the two milks. A total of 599 whey proteins were identified quantitatively, 60 of which were differentially expressed proteins. Bioinformatics analysis showed that the differentially expressed proteins were mainly involved in the biological processes of transport, subcellular localization, and single biological action, in molecular functions such as apical plasma membrane, extracellular region, and extracellular region part, and in cell components including protein binding and anion binding. Nine of the differentially expressed proteins were related to signal transduction and six of them were glycosylated whey proteins. In addition, protein-protein interaction network analysis revealed that some of these differentially expressed proteins were the key whey protein factors with high connectivity. This study provides a theoretical basis for improving bovine colostrum and mature milk quality and developing milk powder for infants and young children and functional dairy foods in the future.