Dynamic changes of sucrose, fructose, glucose contents and differences in activities of sucrose synthase, vacuolar invertase, and cell wall bound invertase in rice grain after flowering stage were studied under natura...Dynamic changes of sucrose, fructose, glucose contents and differences in activities of sucrose synthase, vacuolar invertase, and cell wall bound invertase in rice grain after flowering stage were studied under natural and high temperatures by using two japonica rice varieties Koshihikari and Sasanishiki. In rice grains, the sucrose synthase activity was higher than that of invertase, which was significantly correlated with starch accumulation rate, indicating that the sucrose synthase played an important role in sucrose degradation and starch synthesis. Under high temperature, the significant increase in grain sucrose content without any increase in fructose and glucose contents, suggested that the high temperature treatment enhanced sucrose accumulation, while diminished sucrose degradation in rice grains. Compared with the control plants, the decrease in activities of sucrose synthase, vacuolar invertase, and cell wall bound invertase with high temperature treated plants indicated that the deceleration of sucrose-degradation was related to the decrease in activities of sucrose synthase and invertase.展开更多
In higher plants, vacuolar invertases play essential roles in sugar metabolism, organ development, and sink strength. In sorghum(Sorghum bicolor), two vacuolar invertase genes,Sb VIN1(Sobic. 004 G004800) and Sb VIN2(S...In higher plants, vacuolar invertases play essential roles in sugar metabolism, organ development, and sink strength. In sorghum(Sorghum bicolor), two vacuolar invertase genes,Sb VIN1(Sobic. 004 G004800) and Sb VIN2(Sobic. 006 G160700) have been reported, but their enzymatic properties and functional differences are largely unknown. We combined molecular, biochemical and genomic approaches to investigate their roles in sorghum stem and grain traits. Sb VIN1 and Sb VIN2 showed different expression levels in internodes,leaves, and panicles, indicating that their importance in each organ was different. In an in vitro sucrose hydrolysis assay, proteins of both genes heterologously expressed in Pichia pastoris displayed similar enzyme properties including the same optimum reaction p H(5)and similar Kmfor sucroe(49 mmol L-1 and 45 mmol L-1 for Sb VIN1 and Sb VIN2,respectively). The optimum reaction temperatures of Sb VIN1 and Sb VIN2 were 45 °C and65 °C, respectively. Sb VIN2 showed higher tolerance to high temperature than Sb VIN1. We characterized the sequence variation of these two vacuolar invertase genes in a panel of 216 diverse inbred lines of sweet and grain sorghum and performed gene-based association analysis. Sb VIN1 showed significant associations with stem traits including stem length,stem diameter, internode number, stem fresh weight, and Brix, as well as grain traits including hundred-grain weight and grain width. Significantly associated variation sites were mainly in 5′ upstream and intron regions. Sb VIN2 only associated with grain width and stem water-soluble carbohydrates(WSCs) content. We conclude that the vacuolar invertase genes Sb VIN1 and Sb VIN2 are differently associated with stem and grain traits in sorghum.展开更多
在分析植物液泡转化酶基因保守区序列的基础上,设计1对PCR引物,以番茄(中蔬四号)叶片总RNA的反转录产物为模板,扩增出长为668 bp的cDNA片段,并克隆入pMD-18 T simple载体。测序结果表明,所获得的片段为番茄液泡转化酶基因TIV1的片段;PC...在分析植物液泡转化酶基因保守区序列的基础上,设计1对PCR引物,以番茄(中蔬四号)叶片总RNA的反转录产物为模板,扩增出长为668 bp的cDNA片段,并克隆入pMD-18 T simple载体。测序结果表明,所获得的片段为番茄液泡转化酶基因TIV1的片段;PCR和酶切分析表明,该片段已成功定向连入到双无载体pBinAR的CaMV 35S启动子和OCS终止子间,构建成反义植物表达载体pBinAR-aTIV1;菌落PCR表明质粒成功转化入农杆菌EHA105;瞬时表达证明该反义片段对番茄叶片液泡转化酶活性具有明显的抑制效果。展开更多
文摘Dynamic changes of sucrose, fructose, glucose contents and differences in activities of sucrose synthase, vacuolar invertase, and cell wall bound invertase in rice grain after flowering stage were studied under natural and high temperatures by using two japonica rice varieties Koshihikari and Sasanishiki. In rice grains, the sucrose synthase activity was higher than that of invertase, which was significantly correlated with starch accumulation rate, indicating that the sucrose synthase played an important role in sucrose degradation and starch synthesis. Under high temperature, the significant increase in grain sucrose content without any increase in fructose and glucose contents, suggested that the high temperature treatment enhanced sucrose accumulation, while diminished sucrose degradation in rice grains. Compared with the control plants, the decrease in activities of sucrose synthase, vacuolar invertase, and cell wall bound invertase with high temperature treated plants indicated that the deceleration of sucrose-degradation was related to the decrease in activities of sucrose synthase and invertase.
基金the National Natural Science Foundation of China(No.31471570,No.31461143023)Ministry of Science and Technology of the People's Republic of China(2015BAD15B03).
文摘In higher plants, vacuolar invertases play essential roles in sugar metabolism, organ development, and sink strength. In sorghum(Sorghum bicolor), two vacuolar invertase genes,Sb VIN1(Sobic. 004 G004800) and Sb VIN2(Sobic. 006 G160700) have been reported, but their enzymatic properties and functional differences are largely unknown. We combined molecular, biochemical and genomic approaches to investigate their roles in sorghum stem and grain traits. Sb VIN1 and Sb VIN2 showed different expression levels in internodes,leaves, and panicles, indicating that their importance in each organ was different. In an in vitro sucrose hydrolysis assay, proteins of both genes heterologously expressed in Pichia pastoris displayed similar enzyme properties including the same optimum reaction p H(5)and similar Kmfor sucroe(49 mmol L-1 and 45 mmol L-1 for Sb VIN1 and Sb VIN2,respectively). The optimum reaction temperatures of Sb VIN1 and Sb VIN2 were 45 °C and65 °C, respectively. Sb VIN2 showed higher tolerance to high temperature than Sb VIN1. We characterized the sequence variation of these two vacuolar invertase genes in a panel of 216 diverse inbred lines of sweet and grain sorghum and performed gene-based association analysis. Sb VIN1 showed significant associations with stem traits including stem length,stem diameter, internode number, stem fresh weight, and Brix, as well as grain traits including hundred-grain weight and grain width. Significantly associated variation sites were mainly in 5′ upstream and intron regions. Sb VIN2 only associated with grain width and stem water-soluble carbohydrates(WSCs) content. We conclude that the vacuolar invertase genes Sb VIN1 and Sb VIN2 are differently associated with stem and grain traits in sorghum.
基金国家自然科学基金项目(30370977)国家"十五"科技攻关项目(2004 BA 516A09)
文摘在分析植物液泡转化酶基因保守区序列的基础上,设计1对PCR引物,以番茄(中蔬四号)叶片总RNA的反转录产物为模板,扩增出长为668 bp的cDNA片段,并克隆入pMD-18 T simple载体。测序结果表明,所获得的片段为番茄液泡转化酶基因TIV1的片段;PCR和酶切分析表明,该片段已成功定向连入到双无载体pBinAR的CaMV 35S启动子和OCS终止子间,构建成反义植物表达载体pBinAR-aTIV1;菌落PCR表明质粒成功转化入农杆菌EHA105;瞬时表达证明该反义片段对番茄叶片液泡转化酶活性具有明显的抑制效果。
