Molecular characterization of a new protein complex in plants essential for heterochromatin silencing and genome stability.

植物中对异染色质沉默和基因组稳定性至关重要的新蛋白质复合物的分子表征。

• 批准号: 397811747
• 负责人: Dr. Magdalena Weingartner
• 金额: --
• 依托单位: Team 01: SILENT (aufgelöst)
• 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/397811747?language=en
• 关键词: Molecular; characterization; new; protein; complex

Plants develop through the activity of meristems, which contain pools of self-renewing stem cells that continuously provide new cells for the formation of all tissues and organs. Maintenance of these stem cell populations is essential for successful plant growth and development. Our published work has shown that two genes, which share a conserved transposon-related domain, play a crucial role in the maintenance of the root apical meristem. We named these genes MAINTENANCE of MERISTEM (MAIN) and MAINTENANCE of MERISTEMS LIKE 1 (MAIL1). Loss-of-function mutants for either gene show primary root growth arrest due to accumulation of DNA damage and cell death of stem cells. Moreover, these mutants show release of silencing of a subset of transposable element encoded genes in all tissues, which occurs by a so far unknown mechanism. Our preliminary results indicate that these proteins might be involved in an RNA processing complex. In this project we are aiming at the identification of the molecular function of these proteins by focusing on two complimentary approaches: We will perform Co-Immunoprecipitation experiments followed by mass spectrometry in order to identify the protein complex, in which these proteins act. Second, we will perform a suppressor screen aimed at the identification of the regulatory network that leads to the root growth arrest. Our results will reveal a so far unknown silencing mechanism in plants, which is probably based on RNA processing events. Moreover, we will provide fundamental new insight into the mechanisms that enable plants to maintain genome stability in meristems and to support root growth and re-establishment of stem cell function after DNA damage.

植物通过分生组织的活动发育，分生组织包含自我更新的干细胞库，这些干细胞不断为所有组织和器官的形成提供新细胞。这些干细胞群体的维持对于成功的植物生长和发育是必不可少的。我们已发表的工作表明，两个基因，其中共享一个保守的转座子相关的结构域，发挥了至关重要的作用，在维持根尖分生组织。我们将这些基因命名为分生组织的维持（Main）和分生组织的维持1（MAIL1）。任一基因的功能丧失突变体由于DNA损伤的积累和干细胞的细胞死亡而显示出主根生长停滞。此外，这些突变体显示出在所有组织中转座因子编码基因的子集的沉默的释放，其通过迄今未知的机制发生。我们的初步结果表明，这些蛋白质可能参与RNA加工复合物。在本项目中，我们的目标是通过两种互补的方法来鉴定这些蛋白质的分子功能：我们将进行免疫共沉淀实验，然后进行质谱分析，以鉴定这些蛋白质作用的蛋白质复合物。其次，我们将进行抑制筛选，旨在识别导致根生长停滞的调控网络。我们的研究结果将揭示一个迄今未知的沉默机制在植物中，这可能是基于RNA加工事件。此外，我们将提供基本的新见解的机制，使植物保持基因组稳定性分生组织和支持根生长和重建干细胞功能后DNA损伤。