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（由申请人提供）：葡萄糖是所有生物体中普遍存在的细胞燃料来源，葡萄糖除了在人体中发挥能量作用外，还充当关键的代谢中间体，其中活化的葡萄糖分子实际上被转运到内质网和高尔基体。并用于糖基化蛋白质、脂质和多糖，作为生物合成分泌途径的一部分。葡萄糖和其他膳食单糖进入人体的途径很常见。被小肠的肠细胞吸收并通过血液分布到全身。血浆葡萄糖浓度通过肾脏中的激素控制和保守的重吸收机制来严格维持，从而促进这些吸收/重吸收过程以及排他性递送。内质网和高尔基体固有功能的改变会导致许多人类疾病和病症，例如 II 型糖尿病；因此，对其结构和动力学的复杂了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成员副溶血性弧菌钠/半乳糖同向转运蛋白（vSGLT）的第一个晶体结构。在随后的更新中，我们解决了 vSGLT 向内开放构象的其他结构，结合生化和分子动力学模拟揭示了允许底物释放的机制，在本次资助过程中获得的这两种不同的构象从根本上将我们对膜运输的理解提高到了原子水平，并且是这种竞争的基础。此外，我们的目标是解决哺乳动物转运蛋白（特别是智人）的 SGLT（SLC5 家族）以及一种独特的、结构上尚未解决的核苷酸糖转运蛋白，即 SLC35 家族。目标 1 使用双电子-电子共振和广角 X 射线散射捕获 vSGLT 的完整传输周期，目标 2 和 3 从结构上解决了两类人类转运蛋白。与药物相关的溶质钠转运蛋白家族 (SLC5) 和核苷酸糖转运蛋白家族 (SLC35) 阐明这些转运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。