Structural and functional characterization of sugar transporters in health and disease

健康和疾病中糖转运蛋白的结构和功能特征

• 批准号: 9137918
• 负责人: Jeffrey S Abramson
• 金额: $ 8.33万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-01 至 2019-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9137918
• 关键词: Baculoviruses; Binding; Binding Sites; Biochemical; Biological Models; Biomedical Research; Blood Circulation; Carrier Proteins; Cell Line; Cells; Collaborations; Complement; Congenital Disorders; Crystallography; Cytoplasm; Data; Diabetes Mellitus; Dietary Monosaccharide; Disease; Drug usage; Electrons; Enterocytes; Environment; Equilibrium; Family; Family member; Foundations; Galactose; Glucose; Glucose Plasma Concentration; Glucose Transporter; Goals; Golgi Apparatus; Grant; Health; Homo sapiens; Hormonal; Human; Human body; Insecta; Kidney; Label; Ligands; Lipids; Mammalian Cell; Maps; Membrane; Metabolic; Metabolism; Molecular Conformation; Monitor; Motion; Movement; Non-Insulin-Dependent Diabetes Mellitus; Organelles; Organism; Pathway interactions; Pharmacologic Substance; Physiology; Polysaccharides; Positioning Attribute; Process; Protein Family; Proteins; Pump; Reaction; Research; Resolution; Role; Sampling; Series; Side; Site; Small Intestines; Sodium; Solutions; Source; Spectrum Analysis; Structure; Time; Transmembrane Transport; Ursidae Family; Vibrio parahaemolyticus; Work; Yeasts; absorption; base; conformational conversion; drug development; experience; human disease; member; molecular dynamics; movie; novel; protein structure; restraint; solute; sugar; sugar nucleotide; symporter; x-ray free-electron laser

 DESCRIPTION (provided by applicant): Glucose is a ubiquitous cellular fuel source in virtually all organisms. In addition to its energetic role in the human body, glucose also serves as a critical metabolic intermediate in which activated glucose molecules are transported to the ER and Golgi and used for glycosylating proteins, lipids and polysaccharides as part of the biosynthetic-secretory pathway. The path of entry to the body is common for glucose and the other dietary monosaccharides, which are absorbed by enterocytes of the small intestine and distributed throughout the body in the bloodstream. The plasma glucose concentration is tightly maintained by hormonal control and conserved reabsorption mechanisms in the kidneys. Secondary active transporters facilitate these absorption/reabsorption processes as well as the exclusive delivery of activated glucose molecules to the ER and Golgi. Alterations in their inherent functions result in numerous human diseases and disorders, such as type II diabetes; thus, an intricate understanding of their structure and dynamics is a critical objective for biomedical research. During the original grant cycle, we solved the first crystal structure for an member of the sodium glucose transporter family, the Vibrio parahaemolyticus sodium/galactose symporter (vSGLT). On the subsequent renewal, we solved additional structures of the inward-open conformation of vSGLT, which in conjunction with biochemical and molecular dynamics simulations reveals the mechanism allowing substrate release. These two distinct conformations obtained during the course of this grant have fundamentally advanced our understanding of membrane transport to an atomic level and are the foundation for this competitive renewal. In addition, we aim to resolve mammalian transporters (in particular Homo sapiens) of SGLT (SLC5 family) as well as a distinct, and as of yet structurally unresolved class of nucleotide sugar transporters, the SLC35 family. The aims of this renewal are: Aim 1 captures a complete transport cycle for vSGLT using double electron-electron resonance and wide-angle x-ray scattering. Aims 2 and 3 structurally resolve two classes of human transporters with pharmaceutical relevance, the Solute Sodium Symporter family (SLC5) and the Nucleotide Sugar Transporters family (SLC35). Elucidating the structural basis for these transport families will increase our understanding of the related diseases and aid in drug development.

 描述(申请人提供)：葡萄糖是几乎所有生物体中普遍存在的细胞燃料来源。除了在人体内的能量作用外，葡萄糖还是一种重要的代谢中间体，在生物合成-分泌途径中，激活的葡萄糖分子被运输到内质网和高尔基体，用于糖基化蛋白质、脂类和多糖。进入体内的途径对于葡萄糖和其他膳食单糖来说是常见的，它们被小肠的肠道细胞吸收，并以血液的形式分布在全身。血糖浓度是由激素控制和肾脏保守的重吸收机制严格维持的。次级活性转运体促进了这些吸收/重吸收过程，以及将激活的葡萄糖分子独占地输送到内质网和高尔基体。它们固有功能的改变会导致许多人类疾病和障碍，如II型糖尿病；因此，对它们的结构和动力学的复杂理解是生物医学研究的关键目标。在最初的资助周期中，我们解决了钠葡萄糖转运蛋白家族的一个成员，副溶血性弧菌钠/半乳糖转运蛋白(VSGLT)的第一个晶体结构。在随后的更新中，我们解决了vSGLT向内开放构象的额外结构，结合生化和分子动力学模拟揭示了允许底物释放的机制。这两种截然不同的构象在这项资助过程中从根本上将我们对膜运输的理解提高到了原子水平，并为这种竞争性更新奠定了基础。此外，我们的目标是解析SGLT(SLC5家族)的哺乳动物转运体(特别是智人)以及一类独特的、结构上尚未解决的核苷酸糖转运体，SLC35家族。这次更新的目的是：AIM 1利用双电子-电子共振和广角X射线散射捕捉到vSGLT的完整传输周期。AIMS 2和3从结构上解析了两类与药物相关的人类转运蛋白，即溶质钠转运蛋白家族(SLC5)和核苷酸糖转运蛋白家族(SLC35)。阐明这些运输家族的结构基础将增加我们对相关疾病的了解，并有助于药物开发。