乙烯刺激橡胶树胶乳黄色体蛋白差异初析

Differential Expression of Hevea Lutoid Protein under Ethylene Stimulation

巴西橡胶树(Hevea brasiliensis)胶乳中的黄色体作为乳管细胞的一种细胞器,其稳定性受乙烯刺激影响。该试验从蛋白差异角度,选取未开割胶树,应用双向凝胶电泳技术(two-dimensional gel electrophoresis,2-DE),比较在乙烯刺激与未刺激条件下,黄色体蛋白的变化情况。结果表明,按蛋白表达量变化差异3倍及以上分析,胶树在乙烯刺激24h后,上调蛋白5个,下调蛋白2个;在乙烯刺激48h后,上调蛋白7个,下调蛋白1个;综合3个处理,先上调后下调的蛋白8个;先下调后上调的蛋白2个。应用质谱技术鉴定了其中部分差异表达蛋白,并进行初步功能分析,表明未开割橡胶树胶乳黄色体受乙烯刺激后,黄色体蛋白发生不同程度复杂变化,各组处理间变化明显。

The lutoids are important organelles in laticiferous cells of rubber trees （Hevea brasiliensis）, and are changed under ethylene stimulation. Latex was collected from untapped rubber trees without ethylene stimulation（ES） and rubber trees applied with ethphon at a concentration of 1%. The bottom fraction was collected as lutoids and then precipitated by TCA/cold acetone to isolate lutoid proteins. The protein samples were run in two-dimensional gel electrophoresis. The resultant data were analyzed with PDQuestTM 2-DE Analysis Software. Twenty five differentially expressed protein spots were found in the 2-DE gel comparison between ES treated and untapped non-stimulated tree. Of the 25 differentially expressed protein spots 7 were found from the latex collected after 24 h of ES, of which 5 spots were up-regulated and 2 spots down-regulated; 8 were found from the latex after 48 h of ES, of which 7 spots were up-regulated and 1 spot down-regulated. Combining 3 treatments, 8 protein spots were up-regulated after 24 h of ES, and then down-regulated after 48 h ES; 2 protein spots were up-regulated after 24 h of ES, and then down-regulated after 48 h of ES. Twelve protein spots which were evidently different among the 25 protein spots were selected for detection by mass spectrometry, four of which were identified. The results showed that the lutoid proteins of latex from the rubber trees were changed in varying degrees when the lutoids were stimulated by the ES.