Inositol as a regulator of seedling development

肌醇作为幼苗发育的调节剂

• 批准号: 242751175
• 负责人: Dr. Sabine Schneider
• 金额: --
• 依托单位: Abteilung Zelluläre Biochemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/242751175?language=en
• 关键词: Inositol; regulator; seedling; development

The cyclic sugar alcohol inositol plays a central role in various metabolic pathways in plants. Inositol can be derived from glucose via de novo-biosynthesis, but also be imported into the cell or released from the vacuole via inositol transport proteins. Changes in intracellular inositol content, e.g. in biosynthesis mutants, lead to pleiotropic effects such as altered levels of inositol-containing membrane components, affected membrane dynamics and defects in seedling development. Moreover, auxin signalling is impaired by changing the membrane localisation of auxin efflux carriers.Arabidopsis thaliana has three transport proteins for the import of inositol into the cytosol: AtINT2 and AtINT4 in the plasma membrane and AtINT1 in the tonoplast. If the AtINT1 protein, which transports inositol out of the vacuole into the cytoplasm, is missing, these Atint1 seedlings show an inhibition of cell elongation in roots and in etiolated hypocotyls. This only occurs when sucrose is added to the growth medium. Atint1 plants grown on medium without sucrose do not show apparent growth differences compared to wild type, but have increased levels of inositol-containing membrane components. Comparison of Atint1 seedlings with mutant plants defective in inositol biosynthesis revealed that the observed phenotypic differences do not rely on inositol deficiency, but rather on imbalance in intracellular inositol distribution.The aim of this project is to unravel the impact of inositol balance maintained by intracellular inositol transport on plant development. Because inositol is involved in many different processes we will perform various approaches to cope with the pleiotropic effects of altered inositol transport. The collection of metabolites analysed will be extended, e.g. phosphorylated inositols with supposed signalling function in plants will be included.It will be analysed, if sucrose plays a role as nutrimental or signalling molecule.Due to the fact that inositol is involved in various metabolic pathways, expression analysis of genes encoding key enzymes in inositol metabolism will reveal which metabolic pathways are changed in the Atint1 mutant compared to wild type.Localisation of auxin effluc carriers in Atint1 seedlings and use of an auxin response marker that visualises auxin distribution in plants will elucidate a potential connection between missing inositol transport and auxin signalling. Additionally, research will focus on further phenotypic differences of Atint1 plants compared to wild type, e.g. gravitropism, for which a contribution of inositol was already described.

环状糖肌醇在植物的各种代谢途径中起着核心作用。肌醇可以通过从头生物合成源自葡萄糖，但也可以进口到细胞中，也可以通过肌醇转运蛋白从液泡中释放到细胞中。细胞内肌醇含量的变化，例如在生物合成突变体中，会导致多效性作用，例如含肌醇的膜成分的水平改变，影响幼苗发育中的膜动力学和缺陷。此外，通过改变生长素外排载体的膜定位来损害生长素信号传导。阿拉比迪托米斯thaliana具有三种转运蛋白，可将肌醇进口到plasmammbrane and atint1中的肌醇中：Atint2和Atint4。如果缺少将肌醇从液泡中传递到液泡中的Atint1蛋白缺失，则这些Atint1幼苗显示出对根中的细胞伸长延长和裂开的降压基的抑制作用。仅当将蔗糖添加到生长培养基中时才发生。与野生型相比，在没有蔗糖的培养基上生长的ATINT1植物不会显示出明显的生长差异，但含肌醇的膜成分水平增加。 ATINT1幼苗与突变植物在肌醇生物合成中有缺陷的比较表明，观察到的表型差异不依赖于肌醇缺乏症，而是基于细胞内肌醇分布的不平衡。该项目的目的是揭示肌张力素平衡植物内含量植物含量对植物性植物的影响的影响。由于肌醇参与了许多不同的过程，因此我们将执行各种方法来应对肌动醇转运改变的多效效应。分析的代谢产物的收集将扩展，例如phosphorylated inositols with supposed signalling function in plants will be included.It will be analysed, if sucrose plays a role as nutrimental or signalling molecule.Due to the fact that inositol is involved in various metabolic pathways, expression analysis of genes encoding key enzymes in inositol metabolism will reveal which metabolic pathways are changed in the Atint1 mutant compared to wild type.Localisation of ATINT1幼苗中的生长素排出携带者以及使用可视化植物中的生长素分布的生长素反应标记物将阐明缺失的肌醇转运与生长素信号传导之间的潜在联系。此外，与野生型相比，研究将集中在Atint1植物的进一步表型差异上，例如已描述了肌醇的贡献。