MODELS FOR GENETIC DISORDERS OF CALCIUM TRANSPORT

钙转运遗传疾病模型

• 批准号: 6627483
• 负责人: GARY EDWARD SHULL
• 金额: $ 47.47万
• 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/6627483
• 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.

这项提议的长期目标是制定一项详细的 了解特定的钙/2+泵在心血管和心脏疾病中的作用 活体肺生理学。正在研究的Ca/2+转运ATPase 是肌浆网钙/2+-三磷酸腺苷酶(SERCA)，它 细胞内储存细胞器和血浆中的钙离子 膜Ca/2+-ATPase(PMCAs)，从细胞中排出Ca/2+。 很明显，SERCA和PMCA作为效应分子控制 钙/2+稳态和信号的关键方面，以及兴奋- 肌肉的收缩偶联；然而，个体的具体作用 人们对异构体知之甚少。为了获得这一信息，我们正在 建立每一种钙/2+泵突变的小鼠模型。我们有 准备了SERCA2，SERCA3和PMCA2零突变的小鼠，并有 在SERCA2杂合子突变体和 血管内皮和上皮依赖的缺陷松弛 SERCA3缺失突变体中的肺平滑肌。在目标1中，我们将制定 PMCA1和PMCA4基因零突变的小鼠，还将 开发一种带有修饰的PMCA1基因的小鼠，该基因只会产生 无处不在的PMCA1b变体，而不是含有酸性钙调蛋白的变体 限制在可兴奋组织中的结合域。这些实验 将检验单个钙/2+泵起作用的一般假设 器官特定功能的基本内务管理，并可能揭示 产生关于特定功能的洞察力的意想不到的表型 这些水泵。在目标2中，我们将分析发展和 每个Ca/2+泵突变的组织病理学后果， 并将利用完整的动物和分离的组织进行研究 为了评估这些泵在心血管和心脏疾病中的生理作用 肺组织。这些实验将检验SERCA的假设 PMCA泵调节心脏收缩能力以及肺和血管 平滑肌张力和收缩能力，这反过来又影响心脏 功能、呼吸道阻力和动脉血压。我们期待着 在这个提案中开发的六个突变小鼠的生命将成为 分析Ca/2+转运机制的有价值的模型 ATPase调节心血管、肺和心脏的生理功能 其他纸巾。