MODELS FOR GENETIC DISORDERS OF CALCIUM TRANSPORT

钙转运遗传疾病模型

• 批准号: 6490635
• 负责人: GARY EDWARD SHULL
• 金额: $ 46.2万
• 依托单位: UNIVERSITY OF CINCINNATI
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-01-01 至 2003-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6490635
• 关键词: calcium flux; calcium indicator; calcium transporting ATPase; disease /disorder model; embryonic stem cell; genetic models; genetically modified animals; heart function; histogenesis; laboratory mouse; lung; model design /development; molecular pathology; muscle tone; mutant; protein structure function; respiratory function; sarcoplasmic reticulum; smooth muscle; vascular smooth muscle; vasomotion

The long-term objective of this proposal is to develop a detailed understanding of the role of specific Ca/2+ pumps in cardiovascular and pulmonary physiology in vivo. The Ca/2+-transporting ATPases being studied are the sarco(endo)plasmic reticulum Ca/2+-ATPases (SERCAs), which sequester Ca/2+ in intracellular storage organelles, and the plasma membrane Ca/2+-ATPases (PMCAs), which extrude Ca/2+ from the cell. It is clear that SERCAs and PMCAs serve as effector molecules controlling critical aspects of Ca/2+ homeostasis and signaling, and excitation- contraction coupling in muscle; however, the specific roles of individual isoforms are poorly understood. To obtain this information we are developing mouse models with mutations in each of the Ca/2+ pumps. We have prepared mice with SERCA2, SERCA3, and PMCA2 null mutations, and have demonstrated defective cardiac function in SERCA2 heterozygous mutants and defective endothelium and epithelium dependent relaxation of vascular and pulmonary smooth muscle in SERCA3 null mutants. In aim 1 we will develop mice with null mutations in the PMCA1 and PMCA4 genes, and will also develop a mouse with a modified PMCA1 gene that will produce only the ubiquitous PMCA1b variant, and not the variants with an acidic calmodulin binding domain that are restricted to excitable tissues. These experiments will test the general hypotheses that individual Ca/2+ pumps serve essential housekeeping on organ-specific functions, and may reveal unexpected phenotypes that yield insights regarding the specific functions of these pumps. In aim 2 we will analyze the developmental and histopathological consequences of mutations in each of the Ca/2+ pumps, and will perform studies using both the intact animal and isolated tissues to assess the physiological role of these pumps in cardiovascular and pulmonary tissues. These experiments will test the hypotheses that SERCA and PMCA pumps regulate cardiac contractility and pulmonary and vascular smooth muscle tone and contractility, which in turn affects cardiac function, airway resistance, and arterial blood pressure. We anticipate that the six mutant mouse lives developed in this proposal will become valuable models for analysis of the mechanisms by which Ca/2+-transporting ATPases modulate physiological functions of cardiovascular, pulmonary, and other tissues.

该提议的长期目标是开发一个详细的 了解特定CA/2+泵在心血管中的作用 体内肺部生理。研究的CA/2+传输ATPases正在研究 是sarco（endo）等离子网状CA/2+-ATPases（SERCAS），它 细胞内存储细胞器中的CA/2+和等离子体 膜Ca/2+ -ATPases（PMCAS），将Ca/2+从细胞中挤出。 显然，SERCA和PMCA充当控制的效应分子 CA/2+稳态和信号传导的关键方面以及激发 - 肌肉的收缩耦合；但是，个人的具体角色 同工型知之甚少。为了获得这些信息，我们是 在每个CA/2+泵中开发具有突变的小鼠模型。我们有 用SERCA2，SERCA3和PMCA2无效突变准备的小鼠，并具有 在SERCA2杂合突变体和 缺陷的内皮和上皮依赖性血管的松弛和 SERCA3无效突变体中的肺平滑肌。在目标1中，我们将发展 PMCA1和PMCA4基因中无效突变的小鼠，也将 开发具有修饰PMCA1基因的小鼠，该基因仅产生 无处不在的PMCA1B变体，而不是具有酸性钙调蛋白的变体 结合结构域仅限于可激发组织。这些实验 将测试单个CA/2+泵服务的一般假设 特定器官功能的必不可少的家政服务，并可能揭示 意外的表型产生有关特定功能的见解 这些泵。在AIM 2中，我们将分析发展和 CA/2+泵中每个突变的组织病理学后果， 并将使用完整的动物和孤立的组织进行研究 评估这些泵在心血管中的生理作用 肺组织。这些实验将检验SERCA的假设 PMCA泵调节心脏收缩性以及肺和血管 平滑的肌肉张力和收缩力，进而影响心脏 功能，气道阻力和动脉血压。我们期待 在该提案中发展了六个突变的鼠标生命 有价值的模型，用于分析CA/2+传输的机制 ATP酶调节心血管，肺和 其他组织。