Wu Xiaoqin, Jiang Li, Yu Mingliang, An Xiujuan, Ma Ruijuan, Yu Zhifang
College of Food Science and Engineering, Nanjing Agricultural University, Nanjing, Jiangsu 210095, PR China.
Institute of Horticulture, Jiangsu Academy of Agriculture, Jiangsu 210014, PR China.
J Proteomics. 2016 Sep 16;147:197-211. doi: 10.1016/j.jprot.2016.06.005. Epub 2016 Jun 8.
Ripening and senescence define the last step of fruit development, which directly affects its commercial value, and mitochondria play a crucial role in these processes. To better understand mitochondrial roles in maintaining and regulating metabolism in storage tissues, highly purified mitochondria were isolated from peach tissues (Prunus persica. cv. Xiahui-8) stored at 4°C and 25°C, respectively, and their proteome was conducted using the method of 2-DE and MALDI-TOF/TOF. Twenty-four (24) differentially expressed proteins (2-fold, p≤0.01) were identified out of more than 300 spots and were divided into six categories by PIR and Uniprot, including oxidative stress (34%), carbon metabolism (29%), respiratory chain (17%), amino acid metabolism and protein biosynthesis (8%), heat shock protein (4%), ion channels (4%). Proteins involved in antioxidative systems, gluconeogenesis, glycolysis, ethanol fermentation were changed significantly in response to high temperature. Storage at 4°C dramatically delayed ripening and senescence processes by postponing the climacteric peak, slowing down carbon metabolism and degradation of cell structure. Besides, low temperature induced the expression of formate dehydrogenase and some amino acid metabolism proteins. Proteins classified in respiratory chain, ion channels showed high coherence with climacteric respiratory burst, and the antioxidative enzymes showed relatively important symptoms on ROS scavenging through orderly expressions.
With the advent of proteomics and mass spectrometry (MS), it becomes possible to identify the specific functions of differentially abundant proteins in peach mitochondria. In the present study, a procedure to isolate mitochondria from peach fruits was established, and the mitochondrial proteome was systematically analyzed by 2-D gel electrophoresis procedures in combination with protein identification by mass spectrometry. Differentially expressed proteins in peach mitochondria during different stages of peach fruit ripening and senescence were characterized. Our data provide a great deal of information likely to enhance the understanding of the mitochondrial function in peach ripening and senescent process during storage.
成熟和衰老决定了果实发育的最后阶段，这直接影响其商业价值，而线粒体在这些过程中起着至关重要的作用。为了更好地理解线粒体在维持和调节贮藏组织代谢中的作用，分别从4°C和25°C贮藏的桃组织（Prunus persica. cv. Xiahui-8）中分离出高度纯化的线粒体，并采用二维电泳（2-DE）和基质辅助激光解吸电离飞行时间串联质谱（MALDI-TOF/TOF）方法对其蛋白质组进行分析。在300多个蛋白点中鉴定出24个差异表达蛋白（2倍变化，p≤0.01），根据蛋白质信息资源（PIR）和通用蛋白质数据库（Uniprot）将其分为六类，包括氧化应激（34%）、碳代谢（29%）、呼吸链（17%）、氨基酸代谢和蛋白质生物合成（8%）、热休克蛋白（4%）、离子通道（4%）。参与抗氧化系统、糖异生、糖酵解、乙醇发酵的蛋白质对高温有显著变化。4°C贮藏通过推迟呼吸跃变峰、减缓碳代谢和细胞结构降解，显著延迟了成熟和衰老过程。此外，低温诱导了甲酸脱氢酶和一些氨基酸代谢蛋白的表达。归类于呼吸链、离子通道的蛋白质与呼吸跃变呼吸爆发高度相关，抗氧化酶通过有序表达在清除活性氧方面表现出相对重要的作用。
随着蛋白质组学和质谱（MS）技术的出现，鉴定桃线粒体中差异丰富蛋白质的特定功能成为可能。在本研究中，建立了从桃果实中分离线粒体的方法，并通过二维凝胶电泳结合质谱蛋白质鉴定对线粒体蛋白质组进行了系统分析。对桃果实成熟和衰老不同阶段桃线粒体中差异表达的蛋白质进行了表征。我们的数据提供了大量信息，可能有助于增强对贮藏期间桃成熟和衰老过程中线粒体功能的理解。
