Adducin and the Membrane Skeleton

内收蛋白和膜骨架

• 批准号: 6983404
• 负责人: LUANNE L PETERS
• 金额: $ 41.26万
• 依托单位: JACKSON LABORATORY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-12-01 至 2007-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6983404
• 关键词: blood pressure; cell component structure /function; cytoskeletal proteins; cytoskeleton; echocardiography; electrocardiography; erythrocytes; gene mutation; gene targeting; genetically modified animals; heart rate; histology; hypertension; ion transport; kidney; laboratory mouse; phenotype; platelets; protein structure function

DESCRIPTION (provided by applicant): The goal of this research is to test the following hypothesis: adducin plays a critical role in the assembly, stability, and function of the membrane skeleton in red blood cells (RBCs), platelets and the kidney. Genetic defects in adducin result in anemia, platelet dysfunction, and aberrant control of systemic blood pressure. The membrane skeleton is a critical component of most vertebrate cells. In vitro studies in mammalian cells and studies in other organisms such as D. melanogaster suggest that adducin plays a critical role in the developmental assembly of the membrane skeleton in the red blood cell (RBC), while data have also emerged showing that adducin is a component of the platelet membrane skeleton and is important in platelet function (e. g., aggregation, formation of filopodia and lamellipodia). Moreover, adducin polymorphisms have been associated with altered RBC and kidney cation transport activity and a hypertensive phenotype in the Milan hypertensive (MHS) rat strain. Notably, the cation transport differences between MHS and normotensive (MNS) control rats are abolished upon removal of the membrane skeleton. In humans, adducin polymorphisms have been associated with hypertension in some but not all populations. Here, we will determine the role of adducin in RBC membrane skeleton assembly and stabilization of the lipid bilayer, platelet function, and RBC cation transport activity and the regulation of systemic blood pressure in vivo using genetically defined mice. The specific aims are to: (1) Determine the role of adducin in RBC membrane skeleton assembly and stabilization. We will generate conditional knockouts of the adducin genes in mice using the loxP system and an interferon-inducible Cre-expressing promoter strain (Mxl-Cre) and perform a complete analysis of the RBC phenotype of each mutant strain (singly and in combination). (2) Determine the role of adducin in platelet physiology and pathophysiology. We will perform a complete battery of platelet function tests in adducin null strains to assess shape change, adhesion and spreading, clot retraction, secretion, aggregation, phosphatidylserine exposure and the incidence of thrombi and infarcts. (3) Determine the role of adducin in RBC cation transport and systemic blood pressure regulation. We will determine RBC cation transporter rates (which mirror transport activities in the kidney), systolic blood pressure and heart rates in adducin null strains. Follow up studies will include electrocardiology and echocardiology.

描述（由申请人提供）：本研究的目的是检验以下假设：内收蛋白在红细胞（RBC）、血小板和肾脏中膜骨架的组装、稳定性和功能中起关键作用。内收蛋白的遗传缺陷导致贫血、血小板功能障碍和全身血压的异常控制。膜骨架是大多数脊椎动物细胞的关键组成部分。在哺乳动物细胞中的体外研究和在其他生物体中的研究，如D。Melanogaster的研究表明，内收蛋白在红细胞（RBC）中膜骨架的发育组装中起关键作用，而数据也显示内收蛋白是血小板膜骨架的组分并且在血小板功能中是重要的（例如，例如，在一个实施例中，聚集、丝状伪足和片状伪足的形成）。此外，内收蛋白多态性与米兰高血压（MHS）大鼠品系中改变的RBC和肾脏阳离子转运活性以及高血压表型相关。值得注意的是，MHS和血压正常（MNS）对照大鼠之间的阳离子转运差异被取消后，去除膜骨架。在人类中，内收蛋白多态性与一些但不是所有人群的高血压相关。在这里，我们将确定内收蛋白在红细胞膜骨架组装和稳定的脂质双层，血小板功能，红细胞阳离子转运活性和全身血压的调节在体内使用遗传定义的小鼠的作用。具体目的是：（1）确定内收蛋白在红细胞膜骨架组装和稳定中的作用。我们将使用loxP系统和干扰素诱导型Cre表达启动子菌株（Mxl-Cre）在小鼠中产生内收蛋白基因的条件性敲除，并对每种突变株（单独和组合）的RBC表型进行完整分析。(2)确定内收蛋白在血小板生理学和病理生理学中的作用。我们将在内收蛋白缺失菌株中进行一系列完整的血小板功能试验，以评估形状变化、粘附和扩散、凝块收缩、分泌、聚集、磷脂酰丝氨酸暴露以及血栓和梗死的发生率。(3)确定内收蛋白在红细胞阳离子转运和全身血压调节中的作用。我们将测定RBC阳离子转运蛋白速率（反映肾脏中的转运活性）、收缩压和内收蛋白无效株的心率。随访研究将包括心电图和超声心动图。