Bipartite regulation of cellular osmosensing in C. elegans

线虫细胞渗透感应的双向调节

• 批准号: 8891709
• 负责人: SAMUEL T LAMITINA
• 金额: $ 20.44万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-01-01 至 2017-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8891709
• 关键词: Address; Adopted; Age; Animal Model; Animals; Applications Grants; Area; Bacteria; Biological Assay; Biology; Boxing; Buffers; Caenorhabditis elegans; Cell Culture Techniques; Cell Volumes; Cell physiology; Cells; Chemicals; Chronic Kidney Failure; Complex; Crowding; Cultured Cells; Cytoskeleton; Data; Defect; Detection; Diabetic Neuropathies; Diagnosis; Disease; Early Diagnosis; Early Intervention; Environment; Exhibits; Extracellular Matrix; Extracellular Matrix Proteins; Failure; Funding; Gene Expression; Genes; Genetic; Health; Homeostasis; Human; Hypertension; Immune response; Integral Membrane Protein; Kidney; Kidney Diseases; Kidney Failure; Knowledge; Lead; Life; Mammalian Cell; Mechanics; Mediating; Membrane; Modeling; Molecular; Molecular Chaperones; Mucins; Names; Osmoregulation; Pathway interactions; Peripheral Nervous System Diseases; Physiological; Physiological Processes; Physiology; Play; Process; Property; Proteins; Quality Control; Regulation; Research; Role; Signal Transduction; Stress; Stress-Induced Protein; Stretching; Subcutaneous Tissue; System; Testing; Tissues; Water; Work; Yeasts; age related; base; blood pressure regulation; cell growth regulation; in vivo; insight; mutant; novel therapeutic intervention; overexpression; polyglutamine; positional cloning; prevent; programs; protein misfolding; protein structure; response; sensor; solute; stressor; urinary

DESCRIPTION (provided by applicant): The physiological process of maintaining cellular solute and water content is termed osmotic homeostasis, or osmoregulation, and is essential for all forms of cellular life. In humans, osmotic homeostasis plays vital roles in several contexs, including regulation of the kidney's urinary concentrating mechanism, control of blood pressure, and activation of immune responses. Osmotic dyshomeostasis is associated with several age- related diseases, including chronic kidney disease, renal failure, hypertension, and peripheral neuropathy. Despite the obvious importance of osmoregulation in both physiological and pathophysiological disease states, little is known about the mechanisms by which animal cells sense and respond to osmotic stress. A better understanding of these mechanisms may allow earlier detection and intervention in age-related diseases. Most studies of osmoregulation have been carried out using cultured cells, which fail to mimic the complex environments in which most cells are found. These studies have led to many hypotheses to explain the mechanism(s) of cellular osmosensing, such as mechanical 'stretching' of the membrane or cytoskeleton, macromolecular crowding, and alterations in cytoplasmic ionic content, to name a few. However, there is little data supporting any of these models. To gain an in vivo perspective on mechanisms of cellular osmosensing in animals, we are studying this process in the model organism C. elegans, in which complex cell-cell and cell- extracellular matrix (ECM) interactions are preserved. Using unbiased forward and reverse genetic approaches, we discovered critical roles for the ECM (Rohlfing et al, PLoS Genetics, 2011) and protein misfolding (Moronetti Mazzeo et al, PNAS, 2012) in the regulation of cellular osmosensing in C. elegans. Based on these findings we hypothesize that animal cells use both mechanotransduction and protein damage detection mechanisms to sense osmotic disturbances and activate osmosensitive gene expression. In Aim 1, we will determine if the C. elegans cuticular ECM acts as a structural 'osmosensor' to transduce information via interactions between the mucin-like protein OSM-8 and a transmembrane protein PTR-23. In Aim 2, we will determine how protein and chemical chaperones prevent protein damage in the context of osmotic stress. In Aim 3, we will examine how ECM and protein damage detection pathways interact with each other to control osmoregulatory physiology. Our studies take maximal advantage of the C. elegans system to fill an important gap in our knowledge of metazoan cell physiology. These findings will provide transformative insights into the conserved process of osmoregulation that will allow us to better understand, detect, and manage age-related diseases of osmotic dyshomeostasis.

描述（由申请人提供）：维持细胞溶质和水含量的生理过程称为渗透稳态或渗透调节，对所有形式的细胞生命都是必不可少的。 在人类中，渗透压稳态在几种情况下起着至关重要的作用，包括调节肾脏的尿浓缩机制、控制血压和激活免疫反应。 渗透压平衡障碍与几种年龄相关疾病有关，包括慢性肾病、肾衰竭、高血压和周围神经病. 尽管渗透压调节在生理和病理生理疾病状态中具有明显的重要性，但对动物细胞感知和响应渗透压的机制知之甚少。 更好地了解这些机制可能有助于早期发现和干预与年龄有关的疾病。 大多数关于细胞周期调控的研究都是使用培养的细胞进行的，这些细胞无法模拟大多数细胞所处的复杂环境。 这些研究导致了许多假说来解释细胞膜敏感的机制，例如膜或细胞骨架的机械“拉伸”、大分子拥挤和细胞质离子含量的改变，仅举几例。 然而，几乎没有数据支持这些模型。 为了在动物体内获得细胞生物传感机制的观点，我们正在研究模式生物C。线虫，其中复杂的细胞-细胞和细胞-细胞外基质（ECM）相互作用被保留。 使用无偏正向和反向遗传方法，我们发现ECM（Rohlfing et al，PLoS Genetics，2011）和蛋白质错误折叠（Moronetti Mazzeo et al，PNAS，2012）在C. 优美的基于这些发现，我们假设动物细胞使用机械转导和蛋白质损伤检测机制来感知渗透压紊乱并激活对渗透压敏感的基因表达。 在目标1中，我们将确定C.线虫表皮ECM作为一种结构性的“生物传感器”，通过粘蛋白样蛋白OSM-8和跨膜蛋白PTR-23之间的相互作用来传递信息。 在目标2中，我们将确定蛋白质和化学分子伴侣如何在渗透胁迫的背景下防止蛋白质损伤。 在目标3中，我们将研究ECM和蛋白质损伤检测途径如何相互作用，以控制ECM调节生理学。 我们的研究最大限度地利用了C。elegans系统填补了我们对后生动物细胞生理学知识的重要空白。 这些发现将为保守的渗透调节过程提供变革性的见解，使我们能够更好地理解，检测和管理与年龄相关的渗透性稳态失调疾病。