Structure and function of X,K ATPase family members

X,K ATP酶家族成员的结构和功能

• 批准号: 7464614
• 负责人: NIKOLAI MODYANOV
• 金额: $ 35.55万
• 依托单位: UNIVERSITY OF TOLEDO HEALTH SCI CAMPUS
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-03-01 至 2008-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7464614
• 关键词: ATP Hydrolysis; ATP phosphohydrolase; Abbreviations; Acids; Amino Acids; Anti-Ulcer Agents; Arrhythmia; Baculoviruses; Bladder; Bufo marinus; C-terminal; Cardiac Glycosides; Catalytic Domain; Cell membrane; Cells; Chimera organism; Chronic; Clinical; Complex; Condition; Confusion; Congestive Heart Failure; Cytoplasmic Tail; Data; Development; Digitalis (genus); Digitalis preparation; Digitoxin; Digoxin; Electrolytes; Enzymes; Exhibits; Facility Construction Funding Category; Family; Family member; Family suidae; Fractionation; Funding; Gene Family; Genes; H(+)-K(+)-Exchanging ATPase; Hand; Homeostasis; Human; Human Genome; Hypokalemia; Ink; Insecta; Ion Pumps; Ion Transport; Ions; K ATPase; Length; Libraries; Location; Maintenance; Membrane; Molecular; Monoclonal Antibodies; Mus; Muscle; Myocardium; N-terminal; Na(+)-K(+)-Exchanging ATPase; Names; Newborn Animals; Nomenclature; Numbers; Pattern; Peptide Fragments; Pharmaceutical Preparations; Phosphorylation; Physiological; Play; Positioning Attribute; Potassium; Preparation; Procedures; Property; Protein Isoforms; Proteins; Publications; Rattus; Reaction; Recombinants; Regulation; Research; Role; Sensitivity and Specificity; Site-Directed Mutagenesis; Skeletal Muscle; Skeletal system; Specificity; Stomach; Structure; Structure-Activity Relationship; Sus scrofa; System; Techniques; Terminology; Testing; Tissues; Xenopus oocyte; base; cardiac glycoside receptors; cardiogenesis; immunoaffinity chromatography; in vivo; inhibitor/antagonist; inorganic phosphate; insight; interest; member; mutant; novel; programs; research study; sodium ion; toad; yeast two hybrid system

DESCRIPTION (provided by applicant): The X,K-ATPases represent a family of structurally related but functionally distinct iontransporting ATPases including receptors for cardiac glycosides (Na,K-ATPase) and anti-ulcer drugs (gastric H,K-ATPase). Studies proposed in this project focus on the molecular aspects of the human nongastric H,K-ATPase, and the muscle-specific beta-m-protein, which is a novel memberof the X,K-ATPase family. Nongastric H,K-ATPase plays an important role in the maintenance of electrolyte homeostasis under pathophysiological conditions. Most significantly, this human ion pump is sensitive to cardiac glycosides, particularly to digoxin and digitoxin, which are widely used in clinical practice. During the previous funding period we have characterized basic ion-transport and catalytic functions of recombinant human nongastric H,K-ATPase via expression in Xenopus oocytes and insect cells. The objective of the first group of proposed studies is to define specific features of reaction mechanism of nongastric H,K-ATPase (Specific Aim 1) and to examine the roles of particular structural motifs and residues in the determination of ion specificity and inhibitor sensitivity of human nongastric H,K-ATPase (Specific Aim 2). The anticipated results should provide new insight into molecular basis of the human nongastric H,K-ATPase functioning and define relationship between members of X,K-ATPase family. The results of our preliminary studies demonstrated that recently identified muscle-specific betam protein exhibits structural features, cellular location and functional roles all of which are clearly different from those of the other X,K-ATPase beta subunits. The unique temporospatial expression pattern suggests that beta-m may play an essential role in development of heart and skeletal muscle. The hypothesis to be tested is that betam is associated in vivo with the protein(s) different from known X,K-ATPase alpha-subunits, thus being a component of an unknown system, which might be an unidentified muscle-specific PATPase. The main objective of Specific Aim 3, is to identify protein counterpart(s) of the muscle specific beta-m. These experiments should clarify the relationship between the beta-m and other proteins in skeletal muscle and heart and provide insight into understanding the beta-m physiological function.

描述（由申请人提供）： X，K-ATP酶代表一个与结构相关但功能上不同的电离电离ATPases的家族，包括心脏糖苷的受体（Na，k-atpase）和抗硫酸药物（胃H，K-ATPase）。该项目中提出的研究集中于人非胃H，K-ATPase和肌肉特异性β-M蛋白的分子方面，该β-M蛋白是X，K-ATPase家族的新成员。 nongastric H，K-ATPase在 在病理生理条件下维持电解质稳态。最多 值得注意的是，该人离子泵对心脏糖苷敏感，特别是对地高辛和地高辛和 数字毒素，广泛用于临床实践。在上一个资金期间我们 已经表征了重组人的基本离子传输和催化功能 非胃H，k-ATPase通过异武卵母细胞和昆虫细胞中的表达。目的 第一组提出的研究是定义反应机理的特定特征 nongastric H，K-ATPase（特定目标1），并检查特定结构基序的作用 以及确定人非胃的离子特异性和抑制剂敏感性的残基 h，k-atpase（特定目标2）。预期的结果应为分子提供新的见解 人类非胃H，K-ATPase功能和定义关系的基础 X，K-ATPase家族的成员。我们的初步研究的结果表明，最近 鉴定出的肌肉特异性β蛋白具有结构特征，细胞位置和 功能作用所有与其他x，k-atpase beta亚基的作用明显不同。 独特的暂时空间表达模式表明，β-M在心脏和骨骼肌的发展中可能起着至关重要的作用。要测试的假设是，β与体内与已知X，K-ATPaseα-亚基的蛋白质相关，因此是未知系统的组成部分，这可能是一个未识别的肌肉特异性patpase。 特定目标3的主要目标是鉴定肌肉特异性β-M的蛋白质对应物。这些实验应阐明骨骼肌和心脏中β-M与其他蛋白质之间的关系，并提供了解β-M生理功能的见解。