Regulation of glucose transporters in skeletal muscle

骨骼肌中葡萄糖转运蛋白的调节

• 批准号: 8100942
• 负责人: JONATHAN S. FISHER
• 金额: $ 38.82万
• 依托单位: SAINT LOUIS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-05-06 至 2015-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8100942
• 关键词: 5' -AMP-activated protein kinase; Adipocytes; Animals; Antioxidants; Ascorbic Acid; Blood; Blood Glucose; C-terminal; Carrier Proteins; Cell Line; Cell surface; Cells; Consensus; Data; Dehydroascorbic Acid; Diet; Epithelial Cells; Exercise; Fatty acid glycerol esters; Free Radicals; GLUT4 gene; Glucose; Glucose Transporter; Goals; Hour; Insulin; Insulin Resistance; Lead; Liver; MAPK14 gene; Maintenance; Mediating; Movement; Mus; Muscle; Muscle Cells; Muscle Fibers; Mutation; Non-Insulin-Dependent Diabetes Mellitus; Patients; Phosphorylation; Phosphorylation Site; Phosphotransferases; Play; Proteins; Reactive Oxygen Species; Recycling; Regulation; Reporting; Research Personnel; Role; SLC2A1 gene; Site; Skeletal Muscle; Substrate Specificity; Tail; Tissues; ascorbate; ataxia telangiectasia mutated protein; glucose transport; improved; novel strategies; prevent; research study; sugar; trafficking

DESCRIPTION (provided by applicant): Regulation of GLUT1, the basal glucose transporter of skeletal muscle and the predominant dehydroascorbic acid (DHA) transporter, has not been fully-elucidated in terms of factors that influence GLUT1 cell surface abundance, GLUT1 trafficking, and GLUT1's activity toward its two substrates in skeletal muscle. Preliminary data suggest that ataxia telangiectasia mutated (ATM) may play a role in regulation of basal glucose transport and GLUT1 abundance in skeletal muscle. In addition, other investigators have reported a potential role for p38 in increasing intrinsic activity of GLUT1 toward glucose transport. There are three C-terminal phosphorylation sites in GLUT1; S490 is known target of ATM, and S473 and T478 match consensus target motifs for ATM and p38, respectively. The goal of the project is to determine the roles of these GLUT1 phosphorylation sites (or activation of the potential kinases for these sites) in regulation of GLUT1 abundance, localization, and activity in cultured skeletal muscle cells or mouse skeletal muscle. Specific Aim 1 of the project is to determine whether S473 and S490 of GLUT1 play roles in regulation of GLUT1 abundance or cell surface localization. The general hypotheses are that phosphorylation of these sites will preserve GLUT1 levels and cell surface localization, while GLUT1 that is not phosphorylated at these sites will be more prone toward internalization and degradation. Effects of S473 and S490 mutations will be determined for GLUT1 abundance, trafficking, and transport activity toward glucose and DHA, and effects of activation of ATM (a potential kinase for both sites) on GLUT1 will also be determined. Specific Aim 2 is to determine whether T478 plays a role in regulation of substrate specificity or intrinsic activity of GLUT1. The hypothesis is that T478 phosphorylation will stimulate increased GLUT1 activity toward glucose and decrease activity toward DHA. Effects of T478 mutations will be determined for intrinsic activity of GLUT1 toward glucose and DHA, though potential effects on GLUT1 abundance and trafficking will also be examined. Effects of activation of p38 (a potential kinase of T478) on GLUT1 activity and trafficking will be determined. Additionally, it will be determined whether factors that alter DHA transport also are associated with changes in levels of reactive oxygen species and/or can influence insulin action in muscle cells. Information provided by this project might be used to develop strategies to increase basal glucose transport in skeletal muscle or to increase DHA transport to support skeletal muscle antioxidant status. PUBLIC HEALTH RELEVANCE: This project will investigate factors that could regulate GLUT1, a protein that allows movement of sugar into skeletal muscle all day long (as opposed to another sugar-transporting protein that is responsible for moving sugar into muscle after meals or exercise). Additionally, the role of GLUT1 in providing the building block for muscle vitamin C, a key antioxidant that destroys free radicals, will be investigated. The goal of the project is to provide information that might be useful in improving blood sugar control or in maintaining antioxidant defenses in muscle.

描述（由申请人提供）：GLUT1（骨骼肌的基础葡萄糖转运蛋白和主要的脱氢抗坏血酸（DHA）转运蛋白）的调节尚未在影响 GLUT1 细胞表面丰度、GLUT1 运输和 GLUT1 的因素方面得到充分阐明。骨骼肌中对其两种底物的活性。初步数据表明，共济失调毛细血管扩张突变（ATM）可能在骨骼肌中基础葡萄糖转运和 GLUT1 丰度的调节中发挥作用。此外，其他研究人员报告了 p38 在增加 GLUT1 对葡萄糖转运的内在活性方面的潜在作用。 GLUT1有3个C端磷酸化位点； S490 是 ATM 的已知靶标，S473 和 T478 分别与 ATM 和 p38 的共有靶基序匹配。该项目的目标是确定这些 GLUT1 磷酸化位点（或这些位点的潜在激酶的激活）在调节培养的骨骼肌细胞或小鼠骨骼肌中的 GLUT1 丰度、定位和活性中的作用。该项目的具体目标1是确定GLUT1的S473和S490是否在GLUT1丰度或细胞表面定位的调节中发挥作用。一般假设是，这些位点的磷酸化将保留 GLUT1 水平和细胞表面定位，而在这些位点未磷酸化的 GLUT1 将更容易内化和降解。将确定 S473 和 S490 突变对 GLUT1 丰度、运输以及对葡萄糖和 DHA 的运输活性的影响，并且还将确定 ATM（这两个位点的潜在激酶）激活对 GLUT1 的影响。具体目标 2 是确定 T478 是否在调节 GLUT1 的底物特异性或内在活性中发挥作用。假设 T478 磷酸化会刺激 GLUT1 对葡萄糖的活性增加，并降低对 DHA 的活性。 T478 突变的影响将取决于 GLUT1 对葡萄糖和 DHA 的内在活性，尽管也将检查对 GLUT1 丰度和运输的潜在影响。将确定 p38（T478 的潜在激酶）激活对 GLUT1 活性和运输的影响。此外，还将确定改变 DHA 转运的因素是否也与活性氧水平的变化有关和/或可以影响肌肉细胞中的胰岛素作用。该项目提供的信息可用于制定增加骨骼肌中基础葡萄糖转运或增加 DHA 转运以支持骨骼肌抗氧化状态的策略。 公共健康相关性：该项目将研究可以调节 GLUT1 的因素，GLUT1 是一种蛋白质，可以让糖整天移动到骨骼肌中（而不是另一种糖转运蛋白，负责在餐后或运动后将糖移动到肌肉中）。此外，还将研究 GLUT1 在提供肌肉维生素 C 的组成部分方面的作用，肌肉维生素 C 是一种破坏自由基的关键抗氧化剂。该项目的目标是提供可能有助于改善血糖控制或维持肌肉抗氧化防御的信息。

项目成果

Role of GLUT1 in regulation of reactive oxygen species.

• DOI: 10.1016/j.redox.2014.03.004
• 发表时间: 2014
• 期刊: REDOX BIOLOGY
• 影响因子: 11.4
• 作者: Andrisse, Stanley;Koehler, Rikki M.;Chen, Joseph E.;Patel, Gaytri D.;Vallurupalli, Vivek R.;Ratliff, Benjamin A.;Warren, Daniel E.;Fisher, Jonathan S.
• 通讯作者: Fisher, Jonathan S.