Functional in planta analysis of a plasma membrane-associated brassinosteroid response pathway

质膜相关油菜素类固醇反应途径的功能性植物分析

• 批准号: 214284280
• 负责人: Professor Dr. Klaus Harter
• 金额: --
• 依托单位: Abteilung für Pflanzenphysiologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2012
• 资助国家: 德国
• 起止时间: 2011-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/214284280?language=en
• 关键词: Functional; planta; analysis; plasma; membrane

Brassinosteroids (BRs) are essential hormones for plant growth and development. The generally accepted “standard” model of the BR response pathway in Arabidopsis includes the perception of BR by the plasma membrane receptor BRI1, its oligomerisation with the coreceptor BAK1 followed by the activation of a signalling cascade finally resulting in the expression of BR-responsive genes. We recently identified a fast, gene expressionindependent BR response pathway that modifies the plasma membrane potential (Em) and the expansion of the cell wall – both crucial processes preceding cell elongation growth. This signal-response pathway comprises at least BRI1 and the plasma membrane P-type ATPase. However, the molecular mechanisms underlying the pathway are not yet fully understood. Using the Em of the plasma membrane and the expansion of the cell wall as quantitative cell physiological readouts, we therefore aim to address the following questions: (i) what are the molecular determinants which enable BRI1 to activate the P-ATPases in the plasma membrane; (ii) does phosphorylation of tyrosines or serine/threonine play a role; (iii) are other elements of the “standard” BR signalling pathway and (iv) further elongation growth-promoting substances required? The majority of the proposed experiments will be carried in living plant cells at quantitative level applying novel spectro-microscopic technologies.

油菜素类固醇 (BR) 是植物生长和发育的必需激素，普遍接受的拟南芥 BR 响应途径“标准”模型包括质膜受体 BRI1 感知 BR、其与辅助受体 BAK1 寡聚化，然后激活 BR。信号级联最终导致 BR 响应基因的表达 我们最近发现了一种快速、不依赖于基因表达的 BR 响应途径，该途径可以改变质膜电位。 (Em) 和细胞壁的扩张——这两个信号反应途径至少包括 BRI1 和膜质 P 型 ATP 酶。然而，该途径的分子机制尚未完全了解。因此，我们利用质膜的 Em 和细胞壁的扩张作为定量的细胞生理读数，旨在解决以下问题：(i) 使 BRI1 能够激活血浆中 P-ATP 酶的分子决定因素是什么。膜；(ii) 酪氨酸或丝氨酸/苏氨酸的磷酸化是否起作用；(iii) “标准”BR 信号通路的其他元件是否起作用；(iv) 是否需要进一步延长生长促进物质？应用新型光谱显微镜技术以定量水平携带在活植物细胞中。