植物类激素植物类受体的激活
Jizong Wang1, Hongju Li2, Zhifu Han1
1Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China.
Nature
|August 27, 2015
概括
其受体 (PSKR) 的植物激素识别涉及结构变化. 结合PSK稳定了受体,促进了与植物生长调节的共同受体的相互作用.
科学领域:
- 植物分子生物学
- 结构生物学
- 生物化学
背景情况:
- 植物硫 (PSK) 是一种调节植物生长和发育的关键激素.
- 通过结合其受体 - - 植物硫受体 (PSKR),一种富含白的重复受体激酶 (LRR-RK) 来发挥其功能.
- 对于PSK感知,PSKR激活和下游信号传输的精确机制仍然基本上是未知的.
研究的目的:
- 阐明其受体Phytosulfokine (PSK) 识别的结构基础.
- 了解PSK结合时PSKR的异质激活机制.
- 确定共受体在PSK介导信号传递中的作用.
主要方法:
- 用X射线结晶学确定了PSKR细胞外LRR域在各种状态 (自由,PSK结合,共受体结合) 的结构.
- 生物化学和遗传分析用于验证结构发现并调查蛋白质相互作用.
- 结构数据与生化和遗传证据相结合,绘制了相互作用界面和功能后果.
主要成果:
- 晶体结构显示PSK与PSKR岛域内的β链结合,形成抗β片.
- PSK 的硫酸盐组与PSKR直接相互作用,增强了对接体的识别.
- 通过稳定用于SERK招募的PSKR岛域,PSK结合促进了PSKR与体胚生成受体类激酶 (SERK) 的异构化.
结论:
- 这项研究为PSKR如何识别PSK并进行异质激活提供了结构基础.
- 通过与PSK结合,可对PSKR进行异质调节,从而促进与共受体的相互作用,而不会直接参与其中.
- 这些发现为设计有针对性的小分子为农业应用调节PSKR活性铺平了道路.
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