Myosin-mediated organelle trafficking in plants

肌球蛋白是真核细胞生存所必需的分子马达。特别是， 非肌肉V类肌球蛋白是遗传、定位和运输所必需的。 酵母、动物和人类的细胞器，而植物具有密切相关的XI类 肌球蛋白。我们已经证明了植物肌球蛋白支持高尔基体堆叠的运输， 过氧化物体和线粒体。此外，我们还发现了新的肌球蛋白功能 Factin组织，整体细胞扩张，极化细胞伸长，以及整个 有机体。我们的建议是为了解决这些基本的 与真核细胞生物学和医学的广泛领域相关的肌肉非依赖性过程。 我们已经建立了植物作为研究高等肌球蛋白功能的高级模型。 真核生物以及成功完成 项目。我们的初步研究强调了肌球蛋白功能的惊人相似之处 植物和脊椎动物。因此，我们处于独特的地位，可以在以下条件下完成研究 两个不相互依赖、但具有协同性质的具体目标。 目的1.确定肌球蛋白在细胞生长和极化伸长中的作用。这将是 通过研究多个基因敲除突变体的细胞结构和动力学完成的。这个 肌球蛋白在F-肌动蛋白组织中的活性与细胞器运输 细胞总膨大、极化细胞伸长以及植物生长发育 将被用来提出一个可测试的机械模型。 目的2.研究肌球蛋白对货物识别的调控机制。这个 将确定细胞器特异的肌球蛋白受体和相关的调节蛋白 使用基于成像的基因筛查和生物信息学。受体的功能 复杂的成分将通过零突变体的表型分析来确定。同舟共济 对于目标1，这一分析将在很大程度上有助于制定一个 肌球蛋白驱动细胞内部动力学的力学模型。 拟议的研究将利用广泛的基因组、生物信息学和细胞 可用于模式植物拟南芥的生物资源。我们对肌球蛋白的研究 在细胞器运输、F-肌动蛋白组织、极化细胞伸长和 生物体大小和繁殖成功的测定开启了一项新的研究 大道。在拟南芥模型中开发的概念和技术进展将为 促进了脊椎动物模型的发展。由于对人类的影响越来越大 健康和疾病，从记忆形成和神经障碍到细胞的致命缺陷 分化为病毒感染，肌球蛋白研究对健康的影响 包括拟南芥在内的真核模型肯定会增长。

Myosins are the molecular motors essential for the viability of eukaryotic cells. In particular, non-muscular class V myosins are required for the inheritance, positioning, and transport of organelles in yeast, animals, and humans, whereas plants possess closely related class XI myosins. We have demonstrated that plant myosins empower trafficking of the Golgi stacks, peroxisomes and mitochondria. Furthermore, we have discovered novel myosin functions in Factin organization, overall cell expansion, polarized cell elongation, and growth of an entire organism. Our proposal is developed to address the mechanisms of these fundamental myosindependent processes relevant to broad areas of eukaryotic cell biology and medicine. We have established plants as an advanced model for studying myosin functions in the higher eukaryotes and generated tools and technologies required for the successful completion of the project. Our preliminary research highlighted striking parallels in myosin functions between plants and vertebrates. Therefore, we are uniquely positioned to complete the research under two Specific Aims that do not depend on each other, but rather have a synergistic nature. Aim 1. To determine roles of myosins in cell growth and polarized elongation. This will be done via investigation of the cell structure and dynamics in multiple knockout mutants. The correlation analysis of the myosin activities in F-actin organization, organelle trafficking, overall cell expansion, elongation of polarized cells, as well as plant growth and development will be used to advance a testable mechanistic model. Aim 2. To investigate mechanisms that control cargo recognition by the myosins. The organelle-specific myosin receptors and associated regulatory proteins will be identified using imaging-based genetic screens and bioinformatics. The functions of the receptor complex components will be determined using phenotypic analysis of null mutants. Together with Aim 1, this analysis will substantially contribute to the development of a general mechanistic model of the myosin-driven cell interior dynamics. The proposed research will take advantage of the extensive genomic, bioinformatics, and cell biology resources available for a model plant Arabidopsis. Our studies into the myosin function in organelle transport, F-actin organization, polarized cell elongation, and determination of the organism size and reproductive success have opened a new research avenue. The conceptual and technical advances developed in Arabidopsis model will inform and facilitate the progress in the vertebrate models. Due to increasing impact on human health and disease, from memory formation and neurological disorders to fatal defects in cell differentiation to viral infection, the health-related implications of the myosin research in all eukaryotic models including Arabidopsis are certain to grow.