Microfilaments in Budding Yeast and the Nematode

出芽酵母和线虫中的微丝

• 批准号: 7924931
• 负责人: Anthony P. Bretscher
• 金额: $ 11.96万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-30 至 2011-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7924931
• 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）：细胞已经进化出建立其组成细胞器的空间顺序并为细胞成分的运输提供方向的机制。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。我们一直在使用芽殖酵母来研究肌动蛋白细胞骨架如何产生这种细胞组织。我们已经证明，由福尔明成核并平行于细胞分裂轴延伸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。我们和其他人还表明，重要的肌球蛋白-V（其重链由 MYO2 编码）使用这些电缆来运输用于极化生长的分泌囊泡以及许多细胞器，包括用于核定向的微管、TGN、液泡、过氧化物酶体等，用于在细胞周期中进行分离。在这次更新中，我们建议扩大对酵母福明的研究，并开展一个新项目，调查福明在简单的多细胞生物体——秀丽隐杆线虫中所发挥的功能的广度。我们还将继续对 Myo2p（高度保守的肌球蛋白-V 家族中最了解的成员）进行研究，以研究它如何选择、传递和释放其货物。具体来说，我们建议解决以下问题：（1）酵母福明的成核活性如何在时间和空间上受到控制？我们建议使用遗传和生化方法来识别与酵母菌 Bnilp 配合的因子，并从生化角度理解这些因子如何发挥作用； (2) formins 具有哪些结构范围？线虫对后生动物常见的几乎所有福明类都有单一的代表性福明。我们将启动一个项目来研究这些不同形式的位置、生化特性和功能； (3) 哪些蛋白质与 Myo2p 一起发挥作用，以及它如何在货物之间进行选择？遗传和细胞生物学研究将扩大，以确定与 Myo2p 在货物选择、调节和货物运输中发挥作用的因素（包括特定的磷酸肌醇）。这些研究将有助于从根本上理解细胞秩序是如何产生的。脊椎动物中相关蛋白的缺陷与疾病相关，包括导致非综合征性耳聋的福尔米松 DNFA1 突变，以及肌球蛋白-V 的突变，例如格里斯利综合征。因此，拟议的研究将深入了解基本的细胞生物学问题并具有临床意义。