Analyzing the role of TXNIP as a universal regulator of glucose transport

分析 TXNIP 作为葡萄糖转运通用调节剂的作用

基本信息

批准号：
10004153
负责人：
Ning Wu
金额：
$ 39.9万
依托单位：
VAN ANDEL RESEARCH INSTITUTE
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-09-15 至 2022-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10004153
关键词：
1-Phosphatidylinositol 3-Kinase 5&apos -AMP-activated protein kinase Acute Adipocytes Adipose tissue Affect Arrestins Biochemical Biological Biological Assay Biological Process Cancerous Carrier Proteins Cell membrane Cells Clathrin Defect Disease Endocytosis Environment Event Exercise Family Foundations Future G-Protein-Coupled Receptors GLUT-1 protein GLUT-3 protein GLUT2 gene GLUT4 gene Glucose Glucose Transporter Growth Growth Factor Human Hyperlipidemia Hyperphagia Hypoglycemia In Vitro Insulin Investigation Knockout Mice Knowledge Learning Lipids Location Malignant Neoplasms Maps Mediating Metabolic Metabolic stress Metabolic syndrome Mitogen-Activated Protein Kinases Modeling Movement Mus Muscle Muscle Fibers Nutrient Organism Pathway interactions Peripheral Phenotype Phosphatidylinositols Phosphorylation Phosphorylation Site Phosphotransferases Physiological Play Post-Translational Protein Processing Postabsorptive Hypoglycemia Proteins Proto-Oncogene Proteins c-akt Regulation Reporting Role SLC2A1 gene Sequence Homology Signal Transduction Site Stress Structure Symptoms System TXNIP gene Testing Tissues Up-Regulation Vitamin D age related blood glucose regulation cell growth cell type extracellular glucose metabolism glucose transport glucose uptake human disease in vivo insight insulin regulation knockout animal member metabolic phenotype metabolic profile prevent protein degradation protein transport prototype response solute therapy development tumor growth upstream kinase

1-Phosphatidylinositol 3-Kinase 5&apos -AMP-activated protein kinase Acute Adipocytes Adipose tissue Affect Arrestins Biochemical Biological Biological Assay Biological Process Cancerous Carrier Proteins Cell membrane Cells Clathrin Defect Disease Endocytosis Environment Event Exercise Family Foundations Future G-Protein-Coupled Receptors GLUT-1 protein GLUT-3 protein GLUT2 gene GLUT4 gene Glucose Glucose Transporter Growth Growth Factor Human Hyperlipidemia Hyperphagia Hypoglycemia In Vitro Insulin Investigation Knockout Mice Knowledge Learning Lipids Location Malignant Neoplasms Maps Mediating Metabolic Metabolic stress Metabolic syndrome Mitogen-Activated Protein Kinases Modeling Movement Mus Muscle Muscle Fibers Nutrient Organism Pathway interactions Peripheral Phenotype Phosphatidylinositols Phosphorylation Phosphorylation Site Phosphotransferases Physiological Play Post-Translational Protein Processing Postabsorptive Hypoglycemia Proteins Proto-Oncogene Proteins c-akt Regulation Reporting Role SLC2A1 gene Sequence Homology Signal Transduction Site Stress Structure Symptoms System TXNIP gene Testing Tissues Up-Regulation Vitamin D age related blood glucose regulation cell growth cell type extracellular glucose metabolism glucose transport glucose uptake human disease in vivo insight insulin regulation knockout animal member metabolic phenotype metabolic profile prevent protein degradation protein transport prototype response solute therapy development tumor growth upstream kinase

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项目摘要

PROJECT SUMMARY Glucose is one of the most highly regulated metabolites for nearly all organisms. In humans, misregulation of glucose metabolism plays a role in many diseases, from systemic metabolic syndrome to cancerous cell growth. This proposal focuses on the glucose transporters (GLUTs) in the solute carrier family 2 (SLC2), which includes the well-known transporters GLUT1, GLUT2, GLUT3, and GLUT4. These transporters facilitate the movement of glucose across the cell membrane following concentration gradients in an energy-independent manner. Since GLUTs serve as gates between the cell and the extracellular environment, their activity must be tightly controlled by both signaling events and metabolite levels. Despite their key roles in the major metabolic tissues, very little is known about GLUT protein-level regulation. Insulin regulation of GLUT4 is the notable exception, but even in this case, many mechanistic details (such as insulin-dependent inhibition of GLUT4 endocytosis) remain unknown. We discovered that an α-arrestin protein, TXNIP (thioredoxin interacting protein), acts as an adaptor between GLUT1 and the clathrin-dependent endocytosis machinery, facilitating GLUT1 endocytosis. The interaction between TXNIP and GLUT1 is signal-dependent: phosphorylation of TXNIP by AMPK (AMP-activated kinase) dissociates TXNIP from GLUT1, preventing GLUT1 endocytosis, thus leading to a rapid increase in glucose influx. Given the sequence and structural homology among the GLUTs, together with signal-induced post- translational modifications found on the TXNIP protein, we aim to show that TXNIP is a universal regulatory node evolved for modulating acute glucose flux response. Specific Aim 1 will analyze the regulation of TXNIP on GLUTs, using GLUT1 as the prototype and developing a detailed map of its interaction through various biochemical assays. The information we learn about GLUT1 will be tested on other GLUTs, particularly GLUT4, to verify the role of TXNIP as a common adaptor for all GLUTs. In this Aim, we will also examine the role of lipids in TXNIP-GLUT interactions to build a foundation for future investigation of GLUT protein trafficking. Specific Aim 2 will focus on the upstream regulation of TXNIP by cell signaling events, particularly growth factor stimulation. We intend to identify upstream kinases and their phosphorylation sites on TXNIP; we also plan to test the effect of this regulation in vivo, using insulin regulation of glucose uptake in muscle and adipose tissue as the model. Muscle- and adipose-specific TXNIP knock-out mice will be generated to examine their metabolic profile. Combined understanding of the upstream and downstream regulatory mechanisms of TXNIP should provide greater insight into how glucose metabolism can be misregulated in human diseases.

项目摘要葡萄糖是几乎所有生物的高度调节代谢物之一。在人类中葡萄糖代谢在许多疾病中起作用，从系统性代谢综合征到取消细胞生长。该提案重点是可溶性载体家族2（SLC2）中的葡萄糖转运蛋白（GLUT），包括众所周知的转运蛋白GLUT1，GLUT2，GLUT3和GLUT4。这些运输者准备了浓度无关的浓度梯度后，葡萄糖在细胞膜上的运动方式。由于插槽用作细胞和细胞外环境之间的大门，因此它们的活性必须为受信号事件和代谢物水平紧密控制。尽管在主要代谢中它们的关键作用组织，对GLUT蛋白水平调节知之甚少。 GLUT4的胰岛素调节是著名的例外，但即使在这种情况下，许多机械细节（例如胰岛素依赖性抑制GLUT4 内吞作用）仍然未知。我们发现一种α-arrestin蛋白TXNIP（硫氧还蛋白相互作用）充当了 GLUT1和依赖性依赖性内吞作用机制，支持GLUT1内吞作用。相互作用 TXNIP和GLUT1之间是信号依赖性的：AMPK（AMP激活激酶）对TXNIP的磷酸化将TXNIP与GLUT1分离，防止GLUT1内吞作用，从而导致葡萄糖迅速增加影响。鉴于间隙之间的序列和结构同源性，以及信号诱导的后 - 在TXNIP蛋白上发现的翻译修饰，我们的目的是表明TXNIP是通用的调节节点进化用于调节急性葡萄糖通量反应。特定的目标1将使用Glut1作为原型分析TXNIP的调节，并开发A 通过各种生化测定法的相互作用的详细地图。我们了解GLUT1的信息将在其他Gluts（特别是Glut4）上进行测试，以验证TXNIP作为所有Gluts的常见适配器的作用。在此目标中，我们还将研究脂质在txnip-glut互动中的作用，以建立未来的基础研究lut蛋白运输的研究。特定的目标2将重点放在细胞对TXNIP的上游调节上信号事件，尤其是增长因子刺激。我们打算识别上游激酶及其 TXNIP上的磷酸化位点；我们还计划使用胰岛素调节测试体内该调节的效果肌肉和脂肪组织中的葡萄糖摄取作为模型。肌肉和脂肪特异性TXNIP敲除将生成小鼠以检查其代谢谱。对上游的结合理解 TXNIP的下游调节机制应更深入地了解葡萄糖代谢如何在人类疾病中被误导。