PP1/PPP1R3蛋白磷酸化修饰通路调控长牡蛎不同品系糖原累积的分子机制研究

牡蛎集约化养殖导致其出现肥满度下降等品质退化问题，产业大而不强现状突出。糖原不仅影响牡蛎肥满度，且影响“蛎味”和存活率，是品质改良关键性状。申请人及所在团队近年关注牡蛎糖原改良，进行遗传解析并培育高糖原品种“海蛎1号”。但仍未解决糖原含量随环境变化波动等问题。主要是对基因受环境影响可逆调控机制不清晰。申请人通过GWAS分析，首次表明蛋白磷酸酶PP1及结合亚基PPP1R3调控蛋白磷酸化修饰是影响糖原合成关键基因。在此基础上本项目深入解析其作用机制：(1)阐明不同亚型PP1与PPP1R3蛋白互做机制及生糖能力差异；(2)PP1/PPP1R3上游受胰岛素通路调控糖原合成机制；(3)磷酸化蛋白组筛选PP1/PPP1R3下游效应基因，阐明在高糖原品系磷酸化差异。本项目将在蛋白翻译后修饰层面阐明贝类糖原累积分子机制。作为环境调控可逆修饰过程，可为优化牡蛎养殖环境提升品质提供重要参考。

The intensive culture model of oysters leads to their quality degradation, such as the decreases of condition index, leading to the high yield and low efficiency of oyster industry. Glycogen could affect the condition index and flavour of oyster, which is an important aspect for oyster quality improvement. In recent five years, the project applicant and her research group mainly focused on glycogen content improvement, which have conducted the genetic analysis and cultured the high glycogen strains "Hai Li 1". However, the glycogen contents fluctuated with seasons and culture conduction, which has not been solved. The main reason is that the functional mechanisms of these candidate genes are not clear. According to the GWAS and variation analysis, the applicant illustrated that the protein phosphorylation process regulated by protein phosphatase PP1 and its binding subunit PPP1R3 is the key process to glycogen synthesis. Based on these, the project conducted the following research: (1) illustrate the protein interaction mechanism between different subtypes of PP1 and PPP1R3 to clarify their functional mechanism; (2) illustrate the regulation mechanism of insulin pathway in the upstream of PP1/PPP1R3 complex; (3) Using the phosphoproteome to screen the downstream regulation genes of PP1/PPP1R3 to clarify the phosphorylation difference between high and low glycogen strains. This project will clarify the molecular mechanism of glycogen accumulation in shellfish at protein post-translational modification level. As the reversible modification process regulated by environment factors, this project will provide an important reference to optimize oyster culture environment to improve oyster quality.