Demonstration Base for International Science & Technology Cooperation of Sichuan Province, Rice Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
Dujiangyan Agricultural and Rural Bureau, Dujiangyan 611830, Sichuan, China.
Biomolecules. 2019 Mar 30;9(4):130. doi: 10.3390/biom9040130.
This work was designated to scrutinize the protein differential expression in natural selenium-enriched and non-selenium-enriched rice using the Isobaric-tags for relative and absolute quantification (iTRAQ) proteomics approach. The extracted proteins were subjected to enzyme digestion, desalting, and identified by iTRAQ coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) technology. High pH C18 separation analysis was performed, and the data were then analyzed by Protein Pilot (V4.5) search engine. Protein differential expression was searched out by comparing relatively quantified proteins. The analysis was conducted using gene ontology (GO), cluster of orthologous groups of proteins (COG) and Kyoto encyclopedia of genes and genomes (KEGG) metabolic pathways. A total of 3235 proteins were detected and 3161 proteins were quantified, of which 401 were differential proteins. 208 down-regulated and 193 up-regulated proteins were unveiled. 77 targeted significant differentially expressed proteins were screened out for further analysis, and were classified into 10 categories: oxidoreductases, transferases, isomerases, heat shock proteins, lyases, hydrolases, ligases, synthetases, tubulin, and actin. The results indicated that the anti-stress, anti-oxidation, active oxygen metabolism, carbohydrate and amino acid metabolism of natural selenium-enriched rice was higher than that of non-selenium rice. The activation of the starch synthesis pathway was found to be bounteous in non-selenium-enriched rice. Cysteine synthase (CYS) and methyltransferase (metE) might be the two key proteins that cause amino acid differences. OsAPx02, CatC, riPHGPX, HSP70 and HSP90 might be the key enzymes regulating antioxidant and anti-stress effect differences in two types of rice. This study provides basic information about deviations in protein mechanism and secondary metabolites in selenium-enriched and non-selenium-enriched rice.
本研究采用同位素标记相对和绝对定量技术（iTRAQ）蛋白质组学方法，旨在研究天然富硒和非富硒水稻中的蛋白质差异表达。提取的蛋白质经过酶解、脱盐后，通过 iTRAQ 与液相色谱-串联质谱（LC-MS/MS）技术进行鉴定。采用高 pH C18 分离分析，然后通过 Protein Pilot（V4.5）搜索引擎对数据进行分析。通过比较相对定量蛋白质来搜索蛋白质的差异表达。利用基因本体（GO）、直系同源簇（COG）和京都基因与基因组百科全书（KEGG）代谢途径对分析结果进行了分析。共检测到 3235 种蛋白质，其中 3161 种蛋白质被定量，其中 401 种蛋白质为差异蛋白。鉴定出 208 个下调蛋白和 193 个上调蛋白。筛选出 77 个靶向显著差异表达蛋白进行进一步分析，将其分为 10 类：氧化还原酶、转移酶、异构酶、热休克蛋白、裂合酶、水解酶、连接酶、合成酶、微管蛋白和肌动蛋白。结果表明，天然富硒水稻的抗应激、抗氧化、活性氧代谢、碳水化合物和氨基酸代谢能力均高于非富硒水稻。发现非富硒水稻中淀粉合成途径的激活较为丰富。半胱氨酸合酶（CYS）和甲基转移酶（metE）可能是导致两种水稻氨基酸差异的两个关键蛋白。OsAPx02、CatC、riPHGPX、HSP70 和 HSP90 可能是调节两种水稻抗氧化和抗应激效应差异的关键酶。本研究为富硒和非富硒水稻中蛋白质机制和次生代谢物的差异提供了基础信息。
