Project 3/Struct. of the CDB3:ankyrin:protein 4.2 complex in erythrocytes by EPR

项目 3/结构。

基本信息

批准号：
7449168
负责人：
ALBERT H BETH
金额：
$ 19.52万
依托单位：
VANDERBILT UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-05-01 至 2013-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7449168
关键词：
Actins Adaptor Signaling Protein Affinity Aldehyde-Lyases Amino Acids Anion Exchangers (Proteins)Ankyrin Repeat Ankyrins Architecture Binding Binding Proteins Blood Circulation Blood capillaries Cardiovascular system Cell Shape Cell Size Cell membrane Cells Class Complex Condition Cytoplasmic Tail DNA Sequence Rearrangement Data Defect Disease Docking Erythrocyte Membrane Erythrocytes Exhibits Family Fluorescence Fructosediphosphate Aldolase Glycophorin C Goals Hemoglobin Hemolysis Hemolytic Anemia Hereditary Spherocytosis Homology Modeling Human Integral Membrane Protein Knowledge Label Laboratories Lead Length Lipid Bilayers Literature Mechanics Membrane Membrane Proteins Methods Microcirculation Modeling Molecular Peripheral Phenotype Physiologic pulse Point Mutation Positioning Attribute Property Proteins Pulse taking Range Relative (related person)Reporting Resolution Shapes Side Site Skeleton Spectrin Spin Labels Structural Models Structure Surface Testing Work adapter protein band 3 protein Tuscaloosa base capillary dimer human SYK protein insight molecular dynamics molecular modeling protein 4.1 protein protein interaction shear stress

项目摘要

Human erythrocytes exhibit an unusual biconcave disc shape together with remarkable stability and deformability, all of which are necessary for their survival in the circulatory system. It is now well established that the unusual cell shape and membrane mechanical properties are due in large part to the presence of an extensive membrane skeleton, composed primarily of the proteins spectrin and actin, that lines the inner membrane surface and to specific bridging interactions between this membrane skeleton and intrinsic membrane proteins in the lipid bilayer. The spectrin-actin skeleton associates with the membrane bilayer via two types of contacts, one involving short actin protofilaments and protein 4.1 interacting with the cytoplasmic domain of glycophorin C, and the second involving the bridging protein ankyrinR and protein 4.2 interacting with the cytoplasmic domain of the anion exchange protein (AE1). This project seeks to characterize the structure of the complex of proteins that forms this second class of bridging interactions in human erythrocytes. This focus is dictated by the knowledge that alterations in this second class of interactions results in spherical erythrocytes with decreased cell size and increased fragility, a condition known clinically as hereditary spherocytosis (HS). HS is a spectrum of diseases, occurring in one family out of 2,000 to 3,000, that present clinically as varying degrees of hemolytic anemia resulting from hemolysis of the spherical erythrocytes when they traverse the microcirculation. Recent data have indicated that 15-20% of HS cases are attributable to AE1 defects and ~50% of HS cases result from ankyrin defects (4). A reduction in protein 4.2 binding to the membrane is also a common finding (5). Studies over the past three decades have led to the definition of the intrinsic and peripheral membrane proteins that assemble to stabilize the erythrocyte membrane (reviewed in (6,7)). A central player in the assembly of these proteins is the cytoplasmic domain of AE1 (also known as band 3). The cytoplasmic domain of band 3 (cdb3) has been hypothesized to serve as an organizing center for binding ankyrinR (8) and protein 4.2 (9) as well as other cytosolic proteins including GAPDH (10,11), aldolase (12), phosphofructokinase (13), hemoglobin (14), hemichromes (15), and p72syk (16). Figure 1 shows a schematic diagram of some of the key protein-protein interactions that have been elucidated.

人类红细胞表现出不寻常的双凹圆盘形状以及显着的稳定性和变形能力，所有这些都是它们在循环系统中生存所必需的。现在已经很完善了不寻常的细胞形状和膜机械性能在很大程度上是由于存在广泛的膜骨架，主要由血影蛋白和肌动蛋白组成，排列在内部膜表面以及该膜骨架和内在的特定桥接相互作用脂双层中的膜蛋白。血影蛋白-肌动蛋白骨架通过以下方式与膜双层结合两种类型的接触，一种涉及短肌动蛋白原丝和与细胞质相互作用的蛋白质 4.1 血型糖蛋白 C 的结构域，第二个涉及桥接蛋白 ankyrinR 和蛋白 4.2 的相互作用具有阴离子交换蛋白（AE1）的细胞质结构域。该项目旨在描述形成人类红细胞中第二类桥接相互作用的蛋白质复合物的结构。这个焦点是由这样的知识决定的：第二类相互作用的改变会导致球形红细胞的细胞尺寸减小且脆性增加，这种情况临床上称为遗传性球形红细胞增多症（HS）。 HS 是一系列疾病，每 2,000 至 3,000 个家庭中就有一个发生，表现为临床上表现为球形红细胞溶血而引起不同程度的溶血性贫血。它们穿过微循环。最近的数据表明 15-20% 的 HS 病例可归因于 AE1 缺陷和约 50% 的 HS 病例是由锚蛋白缺陷引起的 (4)。蛋白质 4.2 结合减少膜也是一个常见的发现 (5)。过去三十年的研究已经确定了内膜和外周膜的定义组装以稳定红细胞膜的蛋白质（在（6,7）中进行了综述）。是球队中的核心球员这些蛋白质的组装是 AE1 的胞质结构域（也称为带 3）。细胞质结构域假设带 3 (cdb3) 是结合 ankyrinR (8) 和蛋白质的组织中心 4.2 (9) 以及其他胞质蛋白，包括 GAPDH (10,11)、醛缩酶 (12)、磷酸果糖激酶 (13)、血红蛋白 (14)、半色素 (15) 和 p72syk (16)。图1为部分关键示意图蛋白质与蛋白质之间的相互作用已被阐明。