淡水鱼宰后骨架蛋白的降解特性与机制研究

One of the key problems of freshwater fish preservation is the maintenance of texture quality. Structural proteins are crucial proteins that affect meat textural properties. However, the system and mechanism researches are very deficient in how the changes of structural proteins affect textural properties in postmortem fish. This project will use Chinese common freshwater fish as the research object, and attribution analysis as a method to drill down from three respects, which are the impact of degradation of structural proteins on fish textural properties, the impact of endogenous protease activities on degradation of structural proteins, and the impact of endogenous protease activation and inactivation pathways on endogenous protease activities in hydrolyzing structural proteins. Also, the project will bring in modern basic medicine and cell biology knowledge for a new view, as to study cascade reaction of endogenous proteases caused by cell change which is triggered by apoptosis procedure from the respect of apoptosis phenomenon in postmortem fish. This research will clarify the essential reason of postmortem fish textural deterioration through analysis of structural proteins degradation and its mechanism. This will provide theoretical basis for the control of fish textural properties in postmortem freshwater fish storage. This project has great academic significance in the implementation of freshwater fish preservation technology and knowledge, and has practical significance to optimize fishery structure, fishery output and fishermen’s income.

淡水鱼保鲜技术的关键问题之一是鱼肉质构品质的保持。骨架蛋白是影响肉制品质构品质的关键蛋白，然而骨架蛋白的变化如何影响宰后鱼肉的质构品质尚缺乏系统性和机理性的研究。本项目以我国大宗淡水鱼作为研究对象，从骨架蛋白降解特性对宰后鱼肉质构品质的影响，内源蛋白酶对骨架蛋白降解特性的影响，内源蛋白酶的活力变化通路对其降解骨架蛋白能力的影响三个方面层层推进，归因分析；并在研究过程中，引入现代基础医学和细胞生物学概念，采用新的思路，从宰后鱼肉发生细胞凋亡的新角度出发，研究由凋亡程序触发的细胞变化导致的各种内源蛋白酶相互联系的级联反应通路。通过以上对骨架蛋白降解特性和机制的研究，以期阐明宰后鱼肉质构劣化的本质原因，从而为调控淡水鱼保鲜过程中的质构品质提供理论依据。本项目的实施对淡水鱼贮运保鲜技术的完善具有重要的学术意义，对优化渔业结构、实现渔业增效、增加渔农收入具有重大的现实意义。

本项目针对骨架蛋白的降解影响淡水鱼保鲜过程中质构劣化的问题开展了基础理论研究。确定了关键肌原纤维骨架蛋白肌间线蛋白、肌钙蛋白、伴肌球蛋白、伴肌动蛋白对淡水鱼肉质构劣化的贡献；明晰了关键小分子和大分子骨架蛋白的降解顺序及其对鱼肉结构和质构的影响；明确了关键内源蛋白酶细胞凋亡酶、钙蛋白酶、组织蛋白酶在鱼肉保鲜过程中活力大小变化，以及对骨架蛋白的降解作用和顺序，并进一步剖析了内源蛋白酶活力通路对质构劣化的影响。项目层层推进，归因分析，阐明了肌原纤维骨架蛋白降解特性和机制，获得了宰后淡水鱼鱼肉质构劣化的本质原因，从而为调控淡水鱼保鲜过程中的质构品质提供了重要的理论依据。