Evolution of phytochrome signalling and nuclear transport

光敏色素信号传导和核运输的进化

• 批准号: 80790529
• 负责人: Professor Dr. Andreas Hiltbrunner
• 金额: --
• 依托单位: Institut für Biologie II
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2012-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/80790529?language=en
• 关键词: Evolution; phytochrome; signalling; nuclear; transport

In seed plants the phytochrome A (phyA) photoreceptor plays a key role in survival in far-red light enriched environments and it is essential for responses to very low intensities of light. After activation by light phyA binds to FHY1, which mediates phyA nuclear transport and accumulation. In contrast, cryptogam phys are believed to be cytosolic and/or membrane associated proteins. Although the split of the phy gene lineage into phyA and other phys occurred only in seed plants FHY1 like proteins can be identified in ferns, mosses and green algae, which do not contain phyA like phys. All these cryptogam FHY1 proteins interact with phyA as well as with cryptogam phys. Interestingly, also other key components of phyA signalling are represented in the Physcomitrella genome suggesting that phyA may have adopted a pre-existing signalling system from cryptogams and that also cryptogam phys have a function in the nucleus. Transgenic Physcomitrella lines expressing YFP tagged phys will be employed to test this hypothesis. Moreover, the FHY1 binding site of phyA/cryptogam phys will be mapped using a random mutagenesis/Y2H approach, which will provide further insight into how phyA signalling and the phy/FHY1 system evolved.

在种子植物中，光敏色素 A (phyA) 光感受器在远红光丰富的环境中的生存中发挥着关键作用，并且对于对极低光强度的反应至关重要。光激活后，phyA 与 FHY1 结合，介导 phyA 核转运和积累。相反，隐花植物被认为是胞质和/或膜相关蛋白。尽管phy基因谱系分裂成phyA和其他phys仅发生在种子植物中，但FHY1样蛋白可以在蕨类植物、苔藓和绿藻中鉴定，这些植物不含有phyA样phys。所有这些 Cryptogam FHY1 蛋白都与 phyA 以及 cryptogam phys 相互作用。有趣的是，Physcomitrella 基因组中还存在 phyA 信号传导的其他关键组成部分，这表明 phyA 可能采用了来自 Cryptogams 的预先存在的信号系统，并且 Cryptogams phys 在细胞核中也具有功能。表达 YFP 标记的 phys 的转基因立碗藓系将用于检验这一假设。此外，phyA/cryptogam phys 的 FHY1 结合位点将使用随机诱变/Y2H 方法进行定位，这将进一步了解 phyA 信号传导和 phy/FHY1 系统如何进化。