线粒体能量代谢蛋白在红心火龙果果皮褐变中的作用机制

Recently, the red pitaya develop rapidly in China and it is popular with consumers delicious due to its tasty and high nutrients. However, the red pitaya, with a thin peel, is highly susceptible to water loss and peel browning during postharvest, causing quality deterioration and huge economic losses. Fruit browning was reported to be closed with energy deficit. Mitochondria is the center of cellular energy metabolism, which plays an important role in fruit ripening and senescence. In this study, we evaluate the relationship between peel browning and energy metabolism of red pitaya fruit. The iTRAQ-based quantitative proteomics is applied to screen the mitochondrial differential proteins involved in peel browning. To elucidate biological functions of differential protein, GO and KEGG pathway enrichment analysis was performed via bioinformatics. Moreover, the expression of their genes will also be analyzed by qRT-PCR. The research results not only offer a new idea for the control of peel browning, but also provide a theoretical basis for the development of storage technology.

红心火龙果近年在我国发展迅速，因其味美可口、营养丰富，深受消费者喜爱。但红心火龙果果皮较薄，采收后极易失水褐变，影响果实的外观品质和商品价值，造成巨大的经济损失。果实褐变的发生与能量亏缺有着紧密关系。线粒体是生物体进行呼吸作用和能量代谢的重要场所，在果实的成熟衰老过程中发挥着重要的作用。本项目以红心火龙果为材料，探究线粒体能量代谢与采后果皮褐变的内在联系，通过iTRAQ定量蛋白质组学技术，筛选贮藏过程中健康和褐变果皮组织的线粒体差异蛋白；对差异蛋白进行GO/KEGG富集分析，研究其生物学功能；利用qRT-PCR技术分析关键线粒体蛋白基因水平的变化，旨在阐明线粒体能量代谢在果皮褐变中的作用机理。研究结果不仅为火龙果果皮褐变的防控提供新思路，而且为研发新的贮藏保鲜技术提供理论依据。

.火龙果营养价值丰富，深受消费者喜爱。但是，火龙果对低温较为敏感，在低温贮藏过程中易发生冷害、褐变，影响果实的外观品质和商品价值。本项目研究了火龙果贮藏过程中的能量代谢变化，并观察了线粒体超微结构，揭示了线粒体能量代谢与果实褐变的内在联系。采用密度梯度离心法提取火龙果线粒体，并采用同位素标记相对和绝对定量（iTRAQ）标记结合液相色谱－串联质谱(LC-MS/MS)技术，研究了非褐变与褐变火龙果蛋白质组，结合生物信息学技术筛选与火龙果褐变相关的线粒体差异蛋白质化。研究了1-MCP和香芹酚（CVR）对火龙果的综合效应。1-MCP+CVR处理导致O2-.、H2O2和脂质过氧化水平降低，同时SOD、CAT和APX活性升高，总酚含量升高。透射电镜观察显示1-MCP+CVR对细胞超微结构有保护作用。研究结果为开发火龙果冷害和褐变控制技术提供了理论依据，同时为其他果品褐变机制研究提供新思路和新视角。 .