Structure and function of X,K ATPase family members

X,K ATP酶家族成员的结构和功能

基本信息

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
项目类别：
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

项目摘要

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 酶代表结构相关但功能不同的离子传输 ATP 酶家族，包括强心苷受体（Na,K-ATP 酶）和抗溃疡药物（胃 H,K-ATP 酶）。该项目提出的研究重点是人类非胃 H,K-ATP 酶和肌肉特异性 β-m 蛋白（X,K-ATP 酶家族的新成员）的分子方面。非胃 H,K-ATP 酶在在病理生理条件下维持电解质稳态。最多值得注意的是，这种人体离子泵对强心苷敏感，特别是地高辛和洋地黄毒苷，广泛应用于临床。在上一个资助期间，我们具有重组人的基本离子传输和催化功能的特征非胃 H,K-ATP 酶通过在爪蟾卵母细胞和昆虫细胞中表达。该计划的目标第一组拟议的研究是定义反应机理的具体特征非胃 H,K-ATP 酶（具体目标 1）并检查特定结构基序的作用和残留物在测定人非胃的离子特异性和抑制剂敏感性中的应用 H,K-ATP 酶（具体目标 2）。预期的结果应该为分子生物学提供新的见解人类非胃 H,K-ATP 酶功能的基础并定义两者之间的关系 X,K-ATP酶家族的成员。我们的初步研究结果表明，最近鉴定出的肌肉特异性 β 蛋白表现出结构特征、细胞位置和所有这些功能都明显不同于其他 X,K-ATP 酶 β 亚基。独特的时空表达模式表明β-m可能在心脏和骨骼肌的发育中发挥重要作用。待测试的假设是 Betam 在体内与不同于已知 X,K-ATP 酶 α 亚基的蛋白质相关，因此是未知系统的组成部分，该系统可能是未识别的肌肉特异性 PATP 酶。具体目标 3 的主要目标是识别肌肉特异性 β-m 的蛋白质对应物。这些实验应阐明 β-m 与骨骼肌和心脏中其他蛋白质之间的关系，并为理解 β-m 的生理功能提供见解。