Motility of plant myosins - structure-function relationships

植物肌球蛋白的运动性 - 结构与功能的关系

• 批准号: 5404257
• 负责人: Professor Dr. Peter Michael Nick
• 金额: --
• 依托单位: Botanisches Institut
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2003
• 资助国家: 德国
• 起止时间: 2002-12-31 至 2006-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5404257?language=en
• 关键词: Motility; plant; myosins; structure; function

Although the typical plant cell is immobile due to rigid cell walls, it harbours a highly active intracellular mobility. This mobility is essential because plant cells are very large and have to adjust to a mostly unbuffered environment. A current topic in plant biology is the signal-dependent establishment of cell polarity by directional transport of signalling components. In this context, plant myosins play a pivotal role. Although they share the basic domains with their animal counterparts, they have been found to differ to such a degree that they had to be assigned to separate classes. The fastest intracellular movements known so far are produced by plant myosins. However, neither the structural base for this high motility nor its biological function have been understood so far. Using members from the myosin classes of higher plants (class VIII and XI), we want to investigate the biochemical properties of these motor proteins by in vitro motility assays focussing on velocity and processivity of the movement, time course of ATP-binding and the association with F-actin. Functionality in vivo will be studied by fluorescent fusion constructs transiently transfected into the intact, homologous system. Using plants that are null-mutants for these myosins, we want to assign specific functions to the individual myosin classes. This will contribute to the question whether specific features of the plant-myosin motor domain can be correlated to specific cellular and/or developmental functions.

虽然典型的植物细胞由于细胞壁坚硬而不能移动，但它具有高度活跃的细胞内流动性。这种移动性是必不可少的，因为植物细胞非常大，必须适应几乎没有缓冲的环境。当前植物生物学的一个课题是通过信号组分的定向转运来建立依赖于信号的细胞极性。在这种情况下，植物肌凝蛋白起着关键作用。尽管它们与同类动物有着相同的基本领域，但人们发现它们的差异如此之大，以至于不得不将它们划分为不同的类别。目前已知的最快的细胞内运动是由植物肌球蛋白产生的。然而，到目前为止，这种高运动性的结构基础及其生物学功能都没有被理解。利用高等植物中肌球蛋白类（VIII类和XI类）的成员，我们希望通过体外运动分析来研究这些运动蛋白的生化特性，重点关注运动的速度和进程、atp结合的时间过程以及与f -肌动蛋白的关联。将通过荧光融合构建体瞬时转染到完整的同源系统中来研究其在体内的功能。利用这些肌凝蛋白的零突变体植物，我们希望为单个肌凝蛋白类分配特定的功能。这将有助于解决植物肌球蛋白运动结构域的特定特征是否与特定的细胞和/或发育功能相关的问题。