植物PIN-FORMED辅素输送器的结构和机制
Kien Lam Ung1, Mikael Winkler1, Lukas Schulz2
1Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.
Nature
|June 29, 2022
概括
植物激素叫做奥克辛对生长至关重要. 新的结构揭示了这种重要植物过程的电梯式机制.
科学领域:
- 植物生物学
- 分子生物学
- 生物化学
背景情况:
- 辅酶是调节生长和发育的重要植物激素.
- 形蛋白 (PIN) 是重要的辅酶流体载体.
- 通过PIN介导的辅酶运输的分子机制尚不清楚.
研究的目的:
- 通过PIN蛋白来阐明辅酶运输的分子机制.
- 介绍Arabidopsis thaliana PIN8的结构和生物物理数据.
主要方法:
- 生物物理分析
- 阿拉比多普西斯塔利亚纳PIN8的X射线晶体学
- 生物化学试验
主要成果:
- 确定了PIN8的三个结构:面向外的 (有/没有辅酶) 和面向内的 (与纳酸结合).
- PIN8形成一个具有明显的运输和支架域的同位素,并具有定义的辅酶结合点.
- 一个电梯类型的运输机制,独立于质子梯度,并由auxin的负电荷驱动,被揭示出来.
结论:
- 建立了由PIN蛋白识别和运输的综合分子模型.
- 这些发现解释了植物中极性auxin运输的中心机制.
- 这项研究提供了植物生理,生长和发育的核心特征.
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