由SWEET蛋白调解的糖流出是花运输的关键步骤
Li-Qing Chen1, Xiao-Qing Qu, Bi-Huei Hou
1Carnegie Institution for Science, 260 Panama Street, Stanford, CA 94305, USA.
概括
研究人员发现,SWEET糖流体输送器对于将糖从中粒细胞转移到花细胞至关重要. 这标明了植物糖运输和花载荷的关键步骤.
科学领域:
- 植物生物学 植物生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 植物主要以糖糖的形式运输固定的碳,在美索菲尔细胞中合成,并转移到花中进行分布.
- 糖糖从合成部位移动到体的精确机制,以及介导细胞流入体的细胞流入,仍然不清楚.
- 糖排放是糖-H(+) (质子) 携带输送器 (SUT) 充满体的先决条件.
研究的目的:
- 为了阐明从中粒细胞到体的糖糖运输机制.
- 为了确定涉及到糖糖流入质中的特定转运体.
- 了解已识别的输送器在体载荷中的作用.
主要方法:
- 使用光学糖感应器监测糖的运动.
- 生成的突变植物在特定的SWEET基因 (AtSWEET11和12) 中进行插入.
- 在floem加载中分析了AtSWEET11和12的本地化和功能.
主要成果:
- 鉴定出一种SWEET糖流输送体的子家族.
- 在SWEET11和12被定位到花细胞的血膜.
- 缺乏功能性的突变植物AtSWEET11和12表现出浮膜负荷的缺陷.
- 揭示了一种两步机制:SWEET介导的从表皮细胞出口,然后是H(+) 合进口到子元素-伴随细胞复合体.
结论:
- 甜味运输体在细胞的糖糖流出中发挥着关键作用,促进了体载荷.
- 这一发现阐明了植物中光合作用碳的长途运输中的重要一步.
- 限制细胞间的糖糖运输可能会限制细胞内碳的可用性,从而可能预防病原体感染.
相关概念视频
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Secondary Active Transport
One example of how cells use the energy contained in electrochemical gradients is demonstrated by glucose transport into cells. The ion vital to this process is sodium (Na+), which is typically present in higher concentrations extracellularly than in the cytosol. Such a concentration difference is due, in part, to the action of an enzyme “pump” embedded in the cellular membrane that actively expels Na+ from a cell. Importantly, as this pump contributes to the high concentration of...
Secondary Active Transport
One example of how cells use the energy contained in electrochemical gradients is demonstrated by glucose transport into cells. The ion vital to this process is sodium (Na+), which is typically present in higher concentrations extracellularly than in the cytosol. Such a concentration difference is due, in part, to the action of an enzyme "pump" embedded in the cellular membrane that actively expels Na+ from a cell. Importantly, as this pump contributes to the high concentration of...
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Facilitated diffusion-glucose transporters (GLUTs) are encoded by the solute-linked carrier (SLC) family 2, subfamily A gene family, or SLC2A. The 14 GLUT protein members are distributed into three classes:
Facilitated diffusion-glucose transporters (GLUTs) are encoded by the solute-linked carrier (SLC) family 2, subfamily A gene family, or SLC2A. The 14 GLUT protein members are distributed into three classes:


