Initiation of starch granules and regulation of the starch granule number per chloroplast in Arabidopsis thaliana

拟南芥淀粉颗粒的引发和每个叶绿体淀粉颗粒数量的调节

• 批准号: 403800719
• 负责人: Professor Dr. Joerg Fettke
• 金额: --
• 依托单位: Institut für Biochemie und Biologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/403800719?language=en
• 关键词: Initiation; starch; granules; regulation; granule

Over the last years the knowledge about starch metabolism, especially about the transitory starch metabolism in Arabidopsis thaliana, is tremendously increased. However, some fundamental questions are still open. Thus, how starch granules are initiated and which regulatory processed exist do determine the number of starch granules per chloroplast. This is also important for starch industrial applications and biotechnology. Recently, two Arabidopsis lines were identified which show a strong reduction in the number of starch granules in the chloroplast, ss4 and dpe2/phs1. Using extensive analyses we showed that more than one pathway of starch initiation exists. Furthermore, we showed that the number of starch granules can be altered by changes in the light/dark regime and by modification of the starch degradation process. Thus, these mutants are an excellent tool to analyse the process of starch initiation in more detail.This proposal uses various experimental approaches and focuses on the following aspects:1. Detailed analyses of PHS1 and DPE2 influences on starch granule formation, by altering the light regime, by alteration of the expression, by expression of inactive versions of these enzymes to distinguish between metabolic or structural functions of the enzymes, and by identify interaction partners of the proteins. 2. Analysis of the specific starch granule parameters3. Modify the starch degradation to identify the link between starch degradation and starch granule initiation.

在过去的几年中，关于淀粉代谢，特别是关于拟南芥中的瞬时淀粉代谢的知识大大增加。然而，一些基本问题仍然悬而未决。因此，淀粉颗粒如何启动以及存在哪些调节过程确实决定了每个叶绿体淀粉颗粒的数量。这对于淀粉工业应用和生物技术也很重要。最近，两个拟南芥品系被发现，其叶绿体中淀粉颗粒的数量显着减少，即 ss4 和 dpe2/phs1。通过广泛的分析，我们发现存在不止一种淀粉引发途径。此外，我们表明淀粉颗粒的数量可以通过光/暗状态的变化和淀粉降解过程的改变来改变。因此，这些突变体是更详细地分析淀粉起始过程的绝佳工具。本提案采用了多种实验方法，重点关注以下几个方面： 1．详细分析 PHS1 和 DPE2 对淀粉颗粒形成的影响，通过改变光照方式、改变表达、通过这些酶的非活性版本的表达来区分酶的代谢或结构功能，以及通过识别蛋白质的相互作用伙伴。 2.具体淀粉颗粒参数分析3．修改淀粉降解以确定淀粉降解和淀粉颗粒引发之间的联系。