基于蛋白质组学的宰后成熟阶段牦牛肉品质变化分子机制研究

Yak is a remarkable bovine species of economical importance in the Qinghai-Tibet Plateau region in China, but serious lack of the research on the quality characteristics of yak meat and the changing rule of beef quality during the ripening process after postmortem is one of the key factors that seriously hinder the advancement of the yak industry for a long time. The project is expected to study systematically the quality characteristics of yak meat and analyze comprehensively the complete proteome of the yak meat with the help of proteomics approach. Some special proteins in roast beef can then be found and their function will be analyzed completely, the process is able to acquire scientifically and completely the quality characteristics of yak meat at the molecular level. The project studies the change of the complete proteome of yak meat during the ripening process after postmortem and analyses the internal correlation between the change of all beef proteins and the change in beef quality parameters using a differential proteomic approach, then some target proteins who have high influence on the quality parameters of yak meat can be selected and obtainted. The molecular mechanism for change in yak meat quality can also be clarified, a set of scientific evaluation index systems and prediction models for the evaluation of beef quality can be mathematically established in the project. Furthermore, the project investigates the complete proteome of yak meat for the first time and can find new functional proteins in beef. Besides, the study provides a theoretical basis to optimize process conditions for beef processing, which is contributed to the maintenance and improvement of excellent quality of yak meat and the sustained, rapid and sound development of the yak industry. At the same time, this study can also provide a reference for the quality improvement of other meat comed from different animals during the ripening process after postmortem.

牦牛是我国青藏高原特有的畜种资源，在藏区经济中占有重要地位，但长期以来，对牦牛肉品质特点及其在宰后成熟阶段的品质变化规律缺乏系统深入的研究，这成为严重制约牦牛产业发展的关键因素之一。本项目拟从蛋白质组学角度对牦牛肉的品质进行系统研究，全面分析牦牛肉的全蛋白质组，寻找牦牛肉中独特的蛋白质并分析其功能，从而在分子层面对牦牛肉的独特品质进行科学全面的认识；通过差异蛋白质组学研究宰后成熟阶段牦牛肉蛋白质组的变化，并分析这些变化与牦牛肉品质变化间的内在关系，筛选对牦牛肉品质具有重要影响的关键蛋白，揭示宰后成熟阶段牦牛肉品质变化的分子作用机制，建立牦牛肉品质科学评价体系及预测模型。本项目的实施不仅将首次对牦牛肉全蛋白质组进行分析，发现牦牛肉中新功能蛋白，也将为加工条件的优化提供理论基础，有助于牦牛肉优良品质的保持和改善，促进牦牛产业的快速健康发展，也为其它畜肉宰后成熟阶段的品质改善提供方法借鉴。

本课题采用蛋白质组学方法研究牦牛肉宰后成熟阶段品质变化，并将其与鲁西黄牛肉进行比较，探索牦牛肉和鲁西黄牛肉品质生物标示物。结果表明，牦牛肉在宰后成熟阶段有89个蛋白质发生差异表达，而鲁西黄牛肉在宰后成熟阶段有82个蛋白质发生差异表达，24种蛋白质获得了鉴定，根据其生物学功能特点分成4类，根据牛肉品质与差异表达蛋白质相关性分析结果表明，腺苷高半胱氨酸酶、腺苷二磷酸核糖精氨酸水解酶、前裂腺素还原酶和腺苷酸激酶异构酶为鲁西黄牛品质标识物。泛素碳末端水解酶异构酶在改善鲁西黄牛肉嫩度方面起到关键的作用。而结构蛋白、热休克蛋白27、26S组织蛋白酶非ATP酶调节亚基8作为牦牛肉成熟时其品质标识物，特别是26S组织蛋白酶非ATP酶调节亚基8在改善牦牛肉嫩度方面起到关键的作用，目前本项目基础研究为牦牛和鲁西黄牛肉后熟肉品质形成起到很好的参考作用。项目资助发表SCI收录论文2篇，核心论文3篇，1篇SCI论文在审、1篇EI论文在审。培养硕士生3名，均在读。项目投入经费50万元，支出41.93万元，剩余经费计划用于本项目研究后续支出。