SWEETs(Sugars will eventually be exported transporter)是近年来新发现的一类重要的糖转运蛋白,调控植物体内的糖转运和分配过程。在菜用豌豆中,有关PsSWEETs基因功能及作用机制的报道甚少。本研究克隆获得了PsSWEET15启动子,长度为1...SWEETs(Sugars will eventually be exported transporter)是近年来新发现的一类重要的糖转运蛋白,调控植物体内的糖转运和分配过程。在菜用豌豆中,有关PsSWEETs基因功能及作用机制的报道甚少。本研究克隆获得了PsSWEET15启动子,长度为1182 bp。通过启动子作用元件分析,发现其含有种子特异表达元件GCN4 motif、光、无氧、乙烯、赤霉素等环境胁迫应答元件以及ERF、DOF、MYB、WRKY、NAC、NF-Y、TCP等多个转录因子结合位点。进一步构建了PsSWEET15启动子酵母单杂诱饵载体pPsSWEET15::HIS3以及菜用豌豆cDNA文库,库容为3.056×10^(8)CFU,插入片段平均长度约1000 bp。研究结果为后续筛选PsSWEET15基因上游转录调控因子并探究PsSWEET15基因调控机制提供了基础。展开更多
One-pot polymerization with macroinitiator is supposed to be a robust, facile way to synthesize well-defined core- shell nanoparticles with fixed shell thickness. To testify this, we investigated the temperature-depen...One-pot polymerization with macroinitiator is supposed to be a robust, facile way to synthesize well-defined core- shell nanoparticles with fixed shell thickness. To testify this, we investigated the temperature-depending morphology evolution of polystyrene （PS） core/poly（N-isopropylacrylamide） （PNIPAM） shell microgel synthesized by one-pot polymerization with PNIPAM-RAFT as macroinitiator in dimethylformamide （DMF） by transmission electron microscopy （TEM）, dynamic/static light scattering （DLS/SLS） and small angle neutron scattering （SANS）. It is revealed that the microgel has a core-shell structure, i.e., the core is made of pure PS, but the shell is composed of both PNIPAM-RAFT macroinitiator and crosslinked PS. In fact, there are 92.0 wt% D20, 6.7 wt% PNIPAM and 1.3 wt% PS in the shell in its aqueous dispersion at 21 ℃; therefore, its shell thickness is much larger than the extended chain length of the macroinitiator as revealed by both SANS and DLS observations. Competitive growth of styrene, divinylbenzene and PNIPAM macroinitiator as well as possible chain transfer from amine proton of PNIPAM side chain may lead to the larger shell thickness, compared with the extended chain length of the macroinitiator. Our work can shed light on the real morphology control in one-pot polymerization.展开更多
文摘SWEETs(Sugars will eventually be exported transporter)是近年来新发现的一类重要的糖转运蛋白,调控植物体内的糖转运和分配过程。在菜用豌豆中,有关PsSWEETs基因功能及作用机制的报道甚少。本研究克隆获得了PsSWEET15启动子,长度为1182 bp。通过启动子作用元件分析,发现其含有种子特异表达元件GCN4 motif、光、无氧、乙烯、赤霉素等环境胁迫应答元件以及ERF、DOF、MYB、WRKY、NAC、NF-Y、TCP等多个转录因子结合位点。进一步构建了PsSWEET15启动子酵母单杂诱饵载体pPsSWEET15::HIS3以及菜用豌豆cDNA文库,库容为3.056×10^(8)CFU,插入片段平均长度约1000 bp。研究结果为后续筛选PsSWEET15基因上游转录调控因子并探究PsSWEET15基因调控机制提供了基础。
基金This work was financially supported by the National Natural Science Foundation of China(Nos.21474119 and 21674020)
文摘One-pot polymerization with macroinitiator is supposed to be a robust, facile way to synthesize well-defined core- shell nanoparticles with fixed shell thickness. To testify this, we investigated the temperature-depending morphology evolution of polystyrene （PS） core/poly（N-isopropylacrylamide） （PNIPAM） shell microgel synthesized by one-pot polymerization with PNIPAM-RAFT as macroinitiator in dimethylformamide （DMF） by transmission electron microscopy （TEM）, dynamic/static light scattering （DLS/SLS） and small angle neutron scattering （SANS）. It is revealed that the microgel has a core-shell structure, i.e., the core is made of pure PS, but the shell is composed of both PNIPAM-RAFT macroinitiator and crosslinked PS. In fact, there are 92.0 wt% D20, 6.7 wt% PNIPAM and 1.3 wt% PS in the shell in its aqueous dispersion at 21 ℃; therefore, its shell thickness is much larger than the extended chain length of the macroinitiator as revealed by both SANS and DLS observations. Competitive growth of styrene, divinylbenzene and PNIPAM macroinitiator as well as possible chain transfer from amine proton of PNIPAM side chain may lead to the larger shell thickness, compared with the extended chain length of the macroinitiator. Our work can shed light on the real morphology control in one-pot polymerization.
