The Effects of Glucokinase Polymerization During Metabolic Transitions

葡萄糖激酶聚合在代谢转变过程中的影响

• 批准号: 9304287
• 负责人: patrick renwick stoddard
• 金额: $ 3.19万
• 依托单位: HARVARD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-15 至 2018-07-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9304287
• 关键词: Acceleration; Actins; Affect; Allosteric Regulation; Alpha Cell; Biochemical Pathway; Biochemistry; Biological; Biological Assay; Biological Process; Carbon; Cell Death; Cell Survival; Cells; Conflict (Psychology); Consumption; Cryoelectron Microscopy; Data; Dependence; Diabetes Mellitus; Disease; Environment; Enzymes; Ethanol; Fermentation; Filament; Flow Cytometry; Fluorescence Resonance Energy Transfer; Genes; Genetic; Glucokinase; Glucose; Glycolysis; Goals; Growth; Homeostasis; Investments; Kinetics; Lead; Life; Ligands; Malignant Neoplasms; Measures; Metabolic; Metabolism; Microscopy; Modeling; Nutrient; Phase Transition; Physiological; Play; Polymers; Population; Post-Translational Protein Processing; Production; Proteins; Proteolysis; Proteome; Reporter; Respiration; Risk; Role; Saccharomyces cerevisiae; Saccharomycetales; Site-Directed Mutagenesis; Source; Structural Models; Structure; Subgroup; Testing; Time; Variant; X-Ray Crystallography; Yeasts; alcohol exposure; cell growth; cell killing; cell type; experience; hexokinase; member; mutant; polymerization; pressure; public health relevance; response; structural biology; whole genome

 DESCRIPTION (provided by applicant): The major goal of this project is to understand how metabolic networks are regulated in response to sudden changes in the concentration of environmental nutrients. While we have a good understanding of central carbon metabolism in various steady states, it is unclear how these metabolic networks adapt to maintain viability on timescales that are too short to alter the composition of the proteome. We focus on how the first step in glycolysis is regulated when cells growing slowly on ethanol are exposed to high enough glucose concentrations to induce the high flux through glycolysis that supports rapid, fermentative growth. Starting glycolysis too fast can deplete ATP and kill cells. Preliminary studies suggest that polymerization of a metabolic enzyme plays a crucial role in regulating the kinetics of this transition. We have found that Glucokinase-1 (Glk1), one of the three enzymes responsible for catalyzing the first step in glycolysis, forms linear polymers when respiring cells encounter high glucose concentrations. Purified Glk1 forms polymers in the presence of glucose and ATP and polymerization inhibits Glk1's catalytic activity. Using genetics, we have demonstrated that deleting GLK1 reduces cell death but slows the acceleration of growth rate when respiring cells encounter glucose. Taking advantage of the conservation of glycolysis across all kingdoms of life, we will investigate the way that starved Saccharomyces cerevisiae's metabolism responds to sudden introduction into glucose-rich media as a tractable model for the general response to rapid increases in the environmental glucose concentration. We will tackle this problem at multiple scales: using a combination of genetics, biochemistry and microscopy to understand how Glk1 and its polymerization affect both glycolysis and cellular growth; using a combination of biochemistry and structural biology in order to elucidate how Glk1 polymerization reduces Glk1 enzymatic activity; and determining the conservation of these mechanisms.

 描述（通过应用程序证明）：对代谢网络的主要目标是在环境营养的浓度中响应的，而我们对中心碳代谢的良好态度在各种稳定状态下如何保持款项。在蛋白质组上，当细胞在乙醇上长大的糖基浓度而诱导糖含量的第一步快速耗尽了ATP并杀死细胞。糖酵解的第一步，在呼吸细胞时形成线性聚合物 遇到高葡萄糖浓度。我们将在多个尺度上解决这个问题：使用遗传学，生物化学和显微镜组合，以了解Glk1及其聚合ATOT BOT糖酵解如何使用生物化学生长;减少1个酶促活性；