FERONIA receptor kinase as a cell surface-located regulator for RAC/ROP GTPase-mediated auxin signaling

FERONIA 受体激酶作为 RAC/ROP GTPase 介导的生长素信号传导的细胞表面调节剂

• 批准号: 1146941
• 负责人: Hen-ming Wu
• 金额: $ 8万
• 依托单位: University of Massachusetts Amherst
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-06-15 至 2014-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1146941&HistoricalAwards=false
• 关键词: FERONIA; receptor; kinase; cell; surface

The plant hormone auxin controls both cell growth and cell division and also has a crucial role in determining overall morphology. The molecular-level details of auxin signal perception have been studied for decades. An auxin receptor complex located in the nucleus has been associated with many auxin-regulated processes. It is not clear, however, that this complex can explain the full range of auxin-regulated phenomena, especially those occurring along the cell membrane. Thus, the search for a cell surface-located auxin signaling mechanism continues. This project will extend previous work showing that auxin activates major signal mediators that function along the inner surface of the cell membrane called RAC/ROP GTPases. These important proteins may act as mediators activating surface-located responses. The current project will test whether the transmembrane protein FERONIA could be the missing link connecting extracellular auxin signals to this system. Specifically, this project will determine whether the extracellular domain of FERONIA directly interacts, alone or in a complex, with a low molecular weight extracellular matrix protein called LORELEI-like glucosylphosphatidylinositol-anchored protein1. Biochemical methods such as protein co-immunoprecipitation, pull-down assays and cell biological methods will be used to test for these interactions in plant cells and determine how auxin affects them. Direct auxin-binding studies will be used to test for receptor-ligand interactions between auxin and FERONIA or FERONIA complexes. These crucial experiments testing the potential of FERONIA as a cell surface auxin signaling apparatus will provide training for one graduate student and one postdoctoral fellow.

植物激素生长素控制细胞生长和细胞分裂，并且在确定整体形态方面也起着至关重要的作用。生长素信号感知的分子水平细节已经研究了几十年。位于细胞核的生长素受体复合物与许多生长素调节过程有关。 然而，尚不清楚这种复合物是否可以解释生长素调节的全部现象，特别是沿着细胞膜发生的现象。因此，对位于细胞表面的生长素信号传导机制的探索仍在继续。该项目将扩展之前的工作，表明生长素激活沿着细胞膜内表面（称为 RAC/ROP GTP 酶）发挥作用的主要信号介质。 这些重要的蛋白质可能充当激活表面反应的介质。当前的项目将测试跨膜蛋白 FERONIA 是否可能是将细胞外生长素信号连接到该系统的缺失环节。具体来说，该项目将确定 FERONIA 的胞外结构域是否单独或以复合物形式直接与一种称为 LORELEI 样葡萄糖基磷脂酰肌醇锚定蛋白 1 的低分子量胞外基质蛋白相互作用。蛋白质免疫共沉淀、下拉分析和细胞生物学方法等生化方法将用于测试植物细胞中的这些相互作用，并确定生长素如何影响它们。直接生长素结合研究将用于测试生长素和 FERONIA 或 FERONIA 复合物之间的受体-配体相互作用。 这些关键实验测试了 FERONIA 作为细胞表面生长素信号传导装置的潜力，将为一名研究生和一名博士后提供培训。