烤烟营养生殖转换期叶片生长标志蛋白的筛选

Screening of leaf protein marker during transformation from vegetative growth stage to reproductive stage in flue-cured tobacco

通过双向电泳的方法对烤烟营养、生殖生长转换时期叶片的蛋白质表达谱进行比较研究,鉴定出在两个时期叶片中差异表达的8个标志蛋白。其中有6个蛋白在烤烟营养生长时期的叶片中表达量较高,分别是与光合相关的叶绿体放氧复合蛋白(chloroplast oxygen-evolving complex/thylakoid luminal 25.6kDa protein),光呼吸过程中的关键酶丝氨酸羟甲基转移酶1(SHM1,Serine transhydroxymethyltransferase 1),与蛋白质合成及植物生长发育和细胞分裂有关的核糖体60S与30S蛋白,谷胱甘肽硫转移酶(GST,glutathione S-transferase)和葡聚糖内糖基转移酶(XET,xyloglucan endotransglycosylase)。另外2个碳同化过程中的关键蛋白1,5-二磷酸核酮糖羧化酶/加氧酶Rubisco大亚基(Ribulose-1,5-biphosphate carboxylase/oxygenase large subunit)和小亚基(Small subunit ribulose 1,5-bisphosphate carboxylase)则在烤烟生殖生长时期的叶片中表达量较高。结果表明烤烟在营养向生殖生长转换过程中叶片通过调节关键途径的蛋白表达以降低叶片的呼吸作用、蛋白质合成过程及抗氧化能力,同时增强叶片的碳同化过程。

A comparative study was conducted on protein expression profiling of leaf blade during transformation from vegetative growth stage to reproductive stage in flue-cured tobacco through 2-D electrophoresis, which identified 8 differentially expressed leave protein markers. Among them 6 proteins related to photo-respiratory, protein synthesis and cell development which are chloroplast oxygen-evolving complex/thylakoid luminal 25.6kDa protein, SHM1 （Serine transhydroxymethyltransferase 1）, 60S ribosomal protein and 30S ribosomal protein, GST （glutathione S-transferase） and XET （xyloglucan endotransglycosylase） were shown to be highly expressed in vegetative grown leaves. Ribulose-1,5-biphosphate carboxylase/oxygenase large subunit and small subunit ribulose 1,5-bisphosphate carboxylase which are key enzymes related to carbon fixation were found to have a relative high expression level in reproductive grown leaves. The main differentially expressed proteins between these two stages in tobacco leaves showed that during transformation from vegetative growth stage to reproductive stage the photo-respiratory, protein synthesis and anti-oxidation physiology functions decreased while carbon fixation ability were strengthened through the regulation of expression of related proteins.