Structural Determinants of Glycogen Synthase Regulation

糖原合酶调节的结构决定因素

• 批准号: 8663240
• 负责人: THOMAS D. HURLEY
• 金额: $ 32.92万
• 依托单位: INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2016-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8663240
• 关键词: Active Sites; Affect; Agonist; American; Binding; Binding Sites; Biological Assay; Blood Glucose; Catalysis; Cell Culture Techniques; Cells; Complex; Development; Diabetes Mellitus; Diet; Digestive System Disorders; Discrimination; Disease; Enzymes; Exhibits; Family member; Galactose; Glucosamine; Glucose; Glucose-6-Phosphate; Glycogen; Glycogen (Starch) Synthase; Glycogen Storage Disease; Glycogen storage disease type II; Goals; Hand; Human; Individual; Institutes; Kidney Diseases; Lafora Disease; Lead; Link; Liver Glycogen; Mammalian Cell; Modeling; Molecular; Molecular Conformation; Monitor; Muscle; Mutagenesis; Non-Insulin-Dependent Diabetes Mellitus; Outcome; Pharmaceutical Preparations; Phosphorylation; Polymers; Process; Production; Property; Reaction; Regulation; Research; Site; Specificity; Structure; Structure-Activity Relationship; Testing; Therapeutic; Uridine Diphosphate Glucose; Uridine Diphosphate Sugars; Work; Yeasts; analog; base; diabetic; feeding; glucose disposal; glycosyltransferase; high throughput screening; inhibitor/antagonist; insight; mutant; novel; prevent; screening; small molecule; sugar nucleotide; tool

DESCRIPTION (provided by applicant): The overall goal of this proposal is to understand the structural and functional properties of the enzymes responsible for the synthesis and elongation of the glucose storage polymer, glycogen. Glycogen is an important storage reserve of glucose and the mechanism by which the synthesis of glycogen is initiated and elongated is conserved from yeast to humans. Our recent structural work on yeast glycogen synthase has provided important new insight into the functional properties of all eukaryotic enzymes. The long-range goal of this proposal is to build off this initial work to delineate the structural context for the reaction catalyzed by glycogen synthase and uncover the structural interplay between glycogen association and glucose-6- phosphate activation of glycogen synthase. As part of this effort, we will initialize a screen for small molecule modulators of human glycogen synthase that can manipulate the activity state of the enzyme and promote glucose disposal under conditions found in Type 2 Diabetes or inhibit the action of glycogen synthase as a potential approach for treating glycogen storage disorders, such as Lafora and Pompe's Disease. Structure determination will be an integral part or our efforts as complexes between glycogen synthase and its substrates in combination with glucose-6-phosphate or novel agonists/antagonists of the activator binding site will provide important structure/activity relationships that will guide further development of our research. As part of our screening efforts in Aim 2 we will produce novel enzymatic forms representing homogenous phosphorylation states and these will be tested against the novel modulators of glycogen synthase identified in this aim. In addition, we will pursue structure determination of these novel modulators in the presence and absence of substrates, substrate analogs or glucose-6-phosphate which will link to our work in aim 1. Aim 3 will determine the molecular mechanism of catalysis and the specificity of glycosyltransfer. One of the goals of this aim is to understand whether catalytic mistakes produced by glycogen synthase are ultimately responsible for aberrations in glycogen processing. This aim will draw upon the structural information developed in aim 1 and will employ wild-type and mutant forms of both yeast Gsy2p and human glycogen synthase and will feed important structure/activity information into our modulator discovery and development as part of aim 2.

描述（由申请人提供）：该提案的总体目标是了解负责葡萄糖储存聚合物糖原的合成和延伸的酶的结构和功能特性。糖原是葡萄糖的重要储存储备，糖原合成启动和延长的机制从酵母到人类都是保守的。我们最近对酵母糖原合酶的结构研究为所有真核酶的功能特性提供了重要的新见解。该提案的长期目标是建立在这项初步工作的基础上，以描绘糖原合成酶催化的反应的结构背景，并揭示糖原缔合和糖原合成酶的葡萄糖-6-磷酸激活之间的结构相互作用。作为这项工作的一部分，我们将启动人糖原合酶小分子调节剂的筛选，这些调节剂可以操纵酶的活性状态并促进 2 型糖尿病条件下的葡萄糖处理，或作为潜在方法抑制糖原合酶的作用用于治疗糖原储存障碍，例如拉福拉病和庞贝病。结构测定将是我们努力的一个组成部分，因为糖原合成酶及其底物与葡萄糖-6-磷酸或激活剂结合位点的新型激动剂/拮抗剂相结合的复合物将提供重要的结构/活性关系，这将指导我们的进一步开发研究。作为目标 2 筛选工作的一部分，我们将生产代表同质磷酸化状态的新型酶形式，并将针对该目标中确定的新型糖原合酶调节剂进行测试。此外，我们将在存在和不存在底物、底物类似物或葡萄糖-6-磷酸的情况下对这些新型调节剂进行结构测定，这将与我们的目标 1 的工作联系起来。目标 3 将确定催化的分子机制和特异性糖基转移。该目标的目标之一是了解糖原合酶产生的催化错误是否最终导致糖原加工异常。该目标将利用目标 1 中开发的结构信息，并将采用酵母 Gsy2p 和人糖原合酶的野生型和突变形式，并将重要的结构/活性信息输入到我们的调节剂发现和开发中，作为目标 2 的一部分。