How Cells Control the Properties of Membraneless Organelles to Control Their Function

细胞如何控制无膜细胞器的特性来控制其功能

• 批准号: 9911012
• 负责人: Benjamin Stormo
• 金额: $ 6.53万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-02-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9911012
• 关键词: Address; Affect; Alzheimer' s Disease; Amino Acids; Area; Biological; Biological Assay; Biology; Cell Cycle; Cell Nucleus; Cell physiology; Cells; Charge; Climate; Collection; Cyclins; Cytoplasm; Cytosol; Diffuse; Diffusion; Disease; Environment; Exposure to; Failure; Glutamine; Growth; Huntington Disease; Hyphae; In Vitro; Interphase Cell; Kinetics; Lead; Lipid Bilayers; Liquid substance; Location; Measurable; Measures; Methods; Modeling; Molds; Monitor; Morphogenesis; Nucleic Acids; Organelles; Organism; Pathologic; Pattern; Permeability; Phase; Phenotype; Physiological; Play; Process; Property; Proteins; RNA; RNA Processing; RNA Recognition Motif; Reaction; Regulation; Research; Resolution; Role; Spinocerebellar Ataxias; Stress; Stretching; Structure; System; Temperature; Testing; Thermodynamics; Transcript; United States; Variant; Viscosity; Work; base; biophysical properties; fungus; improved; in vivo; insight; light microscopy; novel; nuclear division; polyglutamine; pressure; protein aggregation; reconstitution

Project Summary – F32 Benjamin Stormo The Control of Membraneless Organelles Material Properties Allows Cells to Control Their Function. How cells pattern and compartmentalize their cytoplasm is a critical question in biology. Recent work has discovered that many cells rely on membraneless organelles. These organelles are not separated from the rest of the cell by a lipid bilayer. Instead membraneless organelles rely on a thermodynamic process called Liquid- Liquid Phase Separation (LLPS) in which a well-mixed solution can spontaneously demix into a concentrated droplet phase and a dilute bulk phase. These liquid-like droplets perform a number of important functions in the cell including RNA processing, altering reaction kinetics, and sequestering transcripts during stress. Droplets have a number of measurable biophysical properties including viscosity, diffusivity, and permeability. Interestingly, in cases where the properties of these droplets have been measured they vary substantially between different types of droplets. Despite these difference we have very little understanding about whether specific properties are important for the function of membraneless organelles, although it has been suggested that dysregulation of droplet properties can result in diseases such as Alzheimer and Huntington. Critically, because phase separation is a thermodynamic process it is influenced by both things within the cells control: i.e. concentration of the components, and things outside of the cells control: i.e. temperature. Our work seeks to understand how the material properties of membraneless organelles affect their function. To do this we will look for evidence that cells control the material properties of droplets following changes in temperature. Our lab has previously used the model filamentous fungus Ashbya gossypii to study liquid-like droplets. In Ashbya membraneless organelles are critical for controlling the cell cycle and polarized growth. Using these clear and relevant physiological readouts along with an in vitro reconstitution system we seek to understand how specific material properties of membraneless organelles are required for specific function in the cell. We will use a unique collection of wild Ashbya isolates collected from around the United States to address two specific aims: 1) How do the primary sequences of droplet components vary between isolates from different climates and how do these sequence changes affect the resulting droplets. 2) How do cells adapt to transient temperature changes to maintain droplet properties in vivo. To answer these questions we will use high resolution light microscopy. Through this work we will improve our understanding of how cells normally regulate the properties of membraneless organelles and how this regulation relates to cellular function. Understanding the role material properties of droplets play in normal function is crucial for understanding what happens when they are altered in disease conditions such as Alzheimer and Huntington.

项目摘要- F32 Benjamin Stormo 控制无膜细胞器的材料特性允许细胞控制其功能。 细胞如何形成和划分细胞质是生物学中的一个关键问题。最近的工作已经 发现许多细胞依赖于无膜细胞器。这些细胞器并没有与其他细胞器分开 细胞的脂质双层。相反，无膜细胞器依赖于一种称为液体的热力学过程。 液相分离（LLPS），其中充分混合的溶液可以自发地分层成浓缩的溶液。 液滴相和稀体相。这些液体状的液滴在微流控系统中执行许多重要功能。 细胞包括RNA加工，改变反应动力学，并在应激过程中螯合转录。液滴 具有许多可测量的生物物理性质，包括粘度、扩散率和渗透性。 有趣的是，在测量这些液滴的性质的情况下，它们的变化很大 不同类型的液滴之间。尽管存在这些差异，我们对是否 尽管有人认为，无膜细胞器的特殊性质对它的功能很重要， 液滴特性的失调可导致诸如阿尔茨海默病和亨廷顿舞蹈症之类的疾病。关键是， 因为相分离是一个热力学过程，所以它受到电池控制内的两个因素的影响： 即成分的浓度，以及细胞控制之外的东西：即温度。 我们的工作旨在了解无膜细胞器的材料特性如何影响其功能。到 这样做，我们将寻找证据表明，细胞控制液滴的材料特性后， 温度本实验室以前曾用模式丝状真菌棉阿舒囊菌研究过液体状 水滴。在阿舒囊菌中，无膜细胞器对于控制细胞周期和极化生长至关重要。 使用这些清晰和相关的生理读数沿着体外重建系统，我们试图 了解无膜细胞器的特定材料特性是如何实现特定功能的， 牢房我们将使用从美国各地收集的独特的野生阿舒囊菌分离株， 解决两个具体的目标：1）液滴组分的主要序列如何在分离株之间变化 以及这些序列变化如何影响产生的液滴。2)细胞如何 适应瞬时温度变化，以保持液滴在体内的特性。为了回答这些问题， 将使用高分辨率光学显微镜。 通过这项工作，我们将提高我们的理解细胞如何正常调节的性质， 无膜细胞器以及这种调节与细胞功能的关系。了解角色材料 液滴在正常功能中的特性对于理解它们被改变时会发生什么至关重要 在阿尔茨海默病和亨廷顿病等疾病中。