外源茉莉酸甲酯诱导的水稻叶片蛋白质差异表达分析

 以抗稻瘟病水稻近等基因系C101LAC及CO39为材料，应用差异蛋白组学技术对外源茉莉酸甲酯（MeJA）诱导8 h和12 h后的水稻叶片蛋白质差异表达变化进行了分析。采用PEG 4000预沉淀法提取水稻叶片总蛋白，经双向电泳、凝胶染色和图像分析，结果表明：与对照相比MeJA处理后的2个水稻品系中共有21个蛋白质表现为2倍以上的表达差异。其中，MeJA处理8 h后，CO39中的差异表达蛋白质点有5个，C101LAC中有8个，U5为2个品系中均新增的蛋白质点。MeJA处理12 h后，CO39中有6个差异表达蛋白质点，C101LAC中则有5个。经胶内酶解、MALDI TOF/TOF质谱分析及数据库检索，成功对21个差异表达蛋白质进行了鉴定，其中新增的蛋白质点U5被鉴定为内切β 1,3 1,4 葡聚糖酶。依据GO数据库和UniProtKB数据库提供的蛋白质注释信息，按照功能可将21个差异表达蛋白质分为8类，分别在植物抗性、氨基酸代谢、信号转导、光合作用、光呼吸、糖代谢、蛋白质合成与分解及细胞代谢等方面发挥作用。

Proteomic analysis of differentially expressed proteins induced by methyl jasmonate in rice leaves

Proteomic approaches using two-dimensional electrophoresis(2-DE) were conducted to identify the differentially expressed proteins in rice leaves in response to methyl jasmonate(MeJA).Proteins were extracted from rice leaves at 8 h and 12 h after treatment with 0.1 mmol/L MeJA and then fractionated using PEG 4000-mediated prefractionation technique before separation by 2-DE.In total,twenty-one proteins resolved in the 2-DE gels were up-regulated or down-regulated in the inoculated rice leaves compared with the controls.At 8 h after treatment with MeJA,5 and 8 differentially expressed proteins in CO39 and C101LAC were identified,respectively.Among them,U5 protein spot was specifically induced in both two rice cultivars.At 12 h,changes of 6 proteins and 5 proteins were detected in CO39 and in C101LAC,respectively.These differentially displayed proteins were successfully identified by in-gel digestion,MALDI-TOF/TOF analysis and database searching.The protein spot U5 was identified as endo-1,3-1,4-beta-D-glucanase.According to protein annotations from GO database and UniProtKB database,the 21 MeJA-responsive proteins were classified into eight categories based on their putative function reported: 1) plant defense response,2) amino-acid biosynthesis,3) signal transduction,4) photosynthesis,5) photorespiratory,6) carbohydrate metabolism,7) protein biosynthesis and proteolysis and 8) metabolic process.