Microfilaments in Budding Yeast and the Nematode

出芽酵母和线虫中的微丝

• 批准号: 7609087
• 负责人: Anthony P. Bretscher
• 金额: $ 48.07万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-02-01 至 2011-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7609087
• 关键词: Actins; Address; Animals; Binding; Biochemical; Biological; Biological Assay; Biology; Caenorhabditis elegans; Cell Cycle; Cell Polarity; Cell division; Cells; Cellular biology; Complement; Cytoskeleton; Defect; Disease; Eukaryota; F-Actin; Family; Filament; Genetic; Genetic Screening; Grant; Growth; Investigation; Location; Microfilaments; Microtubules; Molecular; Morphogenesis; Mothers; Mutation; Myosin ATPase; Myosin Type V; Nematoda; Nuclear; Organelles; Organism; Pathway interactions; Pattern; Phosphatidylinositols; Phosphorylation; Play; Process; Property; Proteins; Regulation; Role; Route; Running; Saccharomycetales; Secretory Vesicles; Site; Structure; Syndrome; Time; Vacuole; Vertebrates; Yeasts; cell growth; cell motility; clinically relevant; deafness; insight; member; peroxisome; profilin; protein function; segregation; tool

DESCRIPTION (provided by applicant): Cells have evolved mechanisms to establish spatial order of their constituent organelles and provide direction for transport of cellular components. This is most apparent in the need for cell polarity and the ability to segregate organelles appropriately during cell division. We have been using the budding yeast to study how the actin cytoskeleton brings about this cellular organization. We have shown that bundles of polarized actin filaments, nucleated by formins and running parallel to the axis of cell division, provide the framework for polarized growth and organelle segregation. We and others have also shown that an essential myosin-V, whose heavy chain is encoded by MYO2, uses these cables to transport secretory vesicles for polarized growth, as well as many organelles, including microtubules for nuclear orientation, the TGN, the vacuole, peroxisomes, etc. for segregation during the cell cycle. In this renewal, we propose to extend our studies on yeast formins, as well as undertake a new project investigating the breadth of functions that formins perform in a simple multicellular organism, the nematode Caenorhabditis elegans. We shall also continue with our studies on Myo2p, the best-understood member of the highly conserved myosin-V family, to investigate how it selects, delivers and releases it cargos. Specifically, we propose to address the following questions: (1) How is the nucleating activity of yeast formins controlled in time and space? We propose to use genetic and biochemical approaches to identify factors that cooperate with the yeast formin Bnilp, and understand in biochemical terms how these function; (2) What is the range of structures that formins perform? The nematode has single representative formins for almost all the classes of formins common to metazoans. We shall initiate a project to study the location, biochemical properties and functions of these different formins; (3) What proteins function with Myo2p, and how does it select between cargos? Genetic and cell biological studies will be expanded to identify factors (including specific phosphoinositides) that function with Myo2p in cargo selection, in its regulation, and in cargo delivery. These studies will contribute to a fundamental understanding of how cellular order is generated. Defects in related proteins in vertebrates are associated with diseases, including mutations in formin DNFA1, resulting in non-syndromic deafness, as well as in myosin-Vs, for example in Griscelli's syndrome. Thus, the proposed studies will provide insight into a basic cell biology question as well as have clinical relevance.

描述（由申请人提供）：细胞已经进化出机制来建立其组成细胞器的空间秩序，并为细胞成分的运输提供方向。这在细胞分裂过程中对细胞极性和适当分离细胞器的能力的需求中最为明显。我们一直在用出芽酵母来研究肌动蛋白细胞骨架是如何形成这种细胞组织的。我们已经证明，由形成蛋白成核并平行于细胞分裂轴的极化肌动蛋白丝束为极化生长和细胞器分离提供了框架。我们和其他人也已经证明，一个重要的肌球蛋白- v，其重链由MYO2编码，使用这些电缆运输极化生长的分泌囊泡，以及许多细胞器，包括用于核取向的微管，TGN，液泡，过氧化物酶体等，在细胞周期中进行分离。在这次更新中，我们建议扩展我们对酵母形成蛋白的研究，并开展一个新的项目，研究形成蛋白在简单的多细胞生物秀丽隐杆线虫中发挥的功能广度。我们还将继续我们对Myo2p的研究，Myo2p是高度保守的肌球蛋白- v家族中最了解的成员，研究它是如何选择、传递和释放它的货物的。具体而言，我们建议解决以下问题：(1)酵母形成蛋白成核活性是如何在时间和空间上控制的？我们建议使用遗传和生物化学的方法来确定与酵母formin Bnilp合作的因素，并从生物化学的角度了解这些因素是如何起作用的；(2)形成的结构范围是什么？线虫在几乎所有后生动物常见的形态中都有单一的代表性形态。我们将展开一项研究计划，研究这些不同形态的位置、生化特性和功能；(3)哪些蛋白与Myo2p一起起作用，Myo2p是如何进行选择的？遗传学和细胞生物学研究将扩大，以确定与Myo2p一起在货物选择、调节和货物运输中起作用的因素（包括特定的磷酸肌苷）。这些研究将有助于对细胞秩序是如何产生的基本理解。脊椎动物中相关蛋白的缺陷与疾病有关，包括双胍DNFA1的突变，导致非综合征性耳聋，以及肌球蛋白- v的突变，例如Griscelli综合征。因此，提出的研究将提供深入了解一个基本的细胞生物学问题，以及具有临床意义。