[ Objective] In this study, the formation mechanism of grain quality of soft wheat was investigated to provide support for soft wheat breeding. [ Meth- od] Using soft and hard wheat varieties as experimental materials...[ Objective] In this study, the formation mechanism of grain quality of soft wheat was investigated to provide support for soft wheat breeding. [ Meth- od] Using soft and hard wheat varieties as experimental materials, changes of Rubisco （ribulose-1,5-bisphosphate carboxylase/oxygenase） degradation in flag leav- es with different quality types during grain fillLing stage were investigated. [ Result] Chlorophyll content and Rubisco content were both gradually reduced in flag leaves of wheat cultivars with different quality types during grain filling stage. Changes of Rubisco content were insignificant at early grain firing stage, but Rubisco content in flag leaves of soft wheat was higher than that of hard wheat at mid-late grain filling stage. Degradation products of Rubisco large subunits with molecular weight of 51 kD could be detected in flag leaves of various wheat cultivars. Rubisco in flag leaves of hard wheat Zheng 9023 was significantly earlier degraded com- pared with Yangnmi 15, indicating that leaf senescence in hard wheat was earlier than soft wheat, which suggested that the protein accumulation in wheat grains may be related with Rubisco degradation in flag leaves after anthesis. [ Conclusion] This study implied the foundation of soft wheat breeding and optimization of cultiva- tion and wheat management in the field.展开更多
Abstract: The degradation of the large subunit (LSU) of ribulose-1, 5–bisphosphate carboxylase/oxygenase (Rubisco; EC 4.1.1.39) in wheat (Triticum aestivum L. cv. Yangmai 158) leaves was investigated. A 50 kDa fragme...Abstract: The degradation of the large subunit (LSU) of ribulose-1, 5–bisphosphate carboxylase/oxygenase (Rubisco; EC 4.1.1.39) in wheat (Triticum aestivum L. cv. Yangmai 158) leaves was investigated. A 50 kDa fragment, a portion of the LSU of Rubisco, was detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting with antibody against tobacco Rubisco in crude enzyme extract of young wheat leaves. The appearance of the 50 kDa fragment was most obvious at 30–35 °C and pH 5.5. The LSU and its 50 kDa fragment both existed when the crude enzyme extract was incubated for 60 min. The amount of LSU decreased with incubation time from 0 to 3 h in crude enzyme extract. However, the 50 kDa fragment could not be found any pH from 4.5 to 8.5 in chloroplast lysates of young wheat leaves. In addition, through treatment with various inhibitors, reactions were inhibited by cysteine proteinase inhibitor E-64 or leupeptin.展开更多
基金Supported by Science and Technology Support Program of Jiangsu Province(BE2012305)Natural Science Foundation of Jiangsu Province(BK2011670)"Twelfth Five-Year" National Science and Technology Support Program of China(2011BAD35B03)
文摘[ Objective] In this study, the formation mechanism of grain quality of soft wheat was investigated to provide support for soft wheat breeding. [ Meth- od] Using soft and hard wheat varieties as experimental materials, changes of Rubisco （ribulose-1,5-bisphosphate carboxylase/oxygenase） degradation in flag leav- es with different quality types during grain fillLing stage were investigated. [ Result] Chlorophyll content and Rubisco content were both gradually reduced in flag leaves of wheat cultivars with different quality types during grain filling stage. Changes of Rubisco content were insignificant at early grain firing stage, but Rubisco content in flag leaves of soft wheat was higher than that of hard wheat at mid-late grain filling stage. Degradation products of Rubisco large subunits with molecular weight of 51 kD could be detected in flag leaves of various wheat cultivars. Rubisco in flag leaves of hard wheat Zheng 9023 was significantly earlier degraded com- pared with Yangnmi 15, indicating that leaf senescence in hard wheat was earlier than soft wheat, which suggested that the protein accumulation in wheat grains may be related with Rubisco degradation in flag leaves after anthesis. [ Conclusion] This study implied the foundation of soft wheat breeding and optimization of cultiva- tion and wheat management in the field.
文摘Abstract: The degradation of the large subunit (LSU) of ribulose-1, 5–bisphosphate carboxylase/oxygenase (Rubisco; EC 4.1.1.39) in wheat (Triticum aestivum L. cv. Yangmai 158) leaves was investigated. A 50 kDa fragment, a portion of the LSU of Rubisco, was detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting with antibody against tobacco Rubisco in crude enzyme extract of young wheat leaves. The appearance of the 50 kDa fragment was most obvious at 30–35 °C and pH 5.5. The LSU and its 50 kDa fragment both existed when the crude enzyme extract was incubated for 60 min. The amount of LSU decreased with incubation time from 0 to 3 h in crude enzyme extract. However, the 50 kDa fragment could not be found any pH from 4.5 to 8.5 in chloroplast lysates of young wheat leaves. In addition, through treatment with various inhibitors, reactions were inhibited by cysteine proteinase inhibitor E-64 or leupeptin.
