Hyperglycemia-induced translational control of gene expression in the retina

高血糖诱导的视网膜基因表达翻译控制

• 批准号: 9057160
• 负责人: Michael D. Dennis
• 金额: $ 24.9万
• 依托单位: PENNSYLVANIA STATE UNIV HERSHEY MED CTR
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2018-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9057160
• 关键词: Ablation; Accounting; Acetylglucosamine; Address; Affect; Age; American; Angiogenic Factor; Binding; Binding Proteins; Blindness; Blood Vessels; C-terminal; Complex; Data; Development; Diabetes Mellitus; Diabetic Retinopathy; Diabetic mouse; Disease; Evidence based treatment; Figs - dietary; Functional disorder; Future; Gene Expression; Gene Expression Profile; Genetic Translation; Glucose; Goals; Growth Factor; Health; Hexosamines; Hyperglycemia; Impairment; Incidence; Individual; Innovative Therapy; Insulin; Internal Ribosome Entry Site; Intervention; Laboratories; Lasers; Lead; Link; Mediating; Mentors; Messenger RNA; Metabolic; Methodology; Modification; Molecular; Outcome; Pathogenesis; Pathway interactions; Patients; Peptide Initiation Factors; Phase; Phosphorylation; Physiological; Play; Poly(A)-Binding Proteins; Prevalence; Prevention; Preventive; Preventive Intervention; Proteins; Regulation; Research; Retina; Retinal; Retinal Detachment; Role; Serine; Signal Transduction; Site; Systems Analysis; Technical Expertise; Testing; Therapeutic Intervention; Threonine; Time; TimeLine; Training; Translations; United States; Up-Regulation; Vascular Endothelial Growth Factors; Vascular Permeabilities; Vision; Work; base; diabetic; innovation; mRNA capping; macular edema; middle age; molecular pathology; neovascularization; novel; pre-clinical; prevent; proliferative diabetic retinopathy; protein degradation; retinal damage; skills; Ablation; Accounting; Acetylglucosamine; Address; Affect; Age; American; Angiogenic Factor; Binding; Binding Proteins; Blindness; Blood Vessels; C-terminal; Complex; Data; Development; Diabetes Mellitus; Diabetic Retinopathy; Diabetic mouse; Disease; Evidence based treatment; Figs - dietary; Functional disorder; Future; Gene Expression; Gene Expression Profile; Genetic Translation; Glucose; Goals; Growth Factor; Health; Hexosamines; Hyperglycemia; Impairment; Incidence; Individual; Innovative Therapy; Insulin; Internal Ribosome Entry Site; Intervention; Laboratories; Lasers; Lead; Link; Mediating; Mentors; Messenger RNA; Metabolic; Methodology; Modification; Molecular; Outcome; Pathogenesis; Pathway interactions; Patients; Peptide Initiation Factors; Phase; Phosphorylation; Physiological; Play; Poly(A)-Binding Proteins; Prevalence; Prevention; Preventive; Preventive Intervention; Proteins; Regulation; Research; Retina; Retinal; Retinal Detachment; Role; Serine; Signal Transduction; Site; Systems Analysis; Technical Expertise; Testing; Therapeutic Intervention; Threonine; Time; TimeLine; Training; Translations; United States; Up-Regulation; Vascular Endothelial Growth Factors; Vascular Permeabilities; Vision; Work; base; diabetic; innovation; mRNA capping; macular edema; middle age; molecular pathology; neovascularization; novel; pre-clinical; prevent; proliferative diabetic retinopathy; protein degradation; retinal damage; skills

DESCRIPTION (provided by applicant): Diabetic retinopathy is the leading cause of blindness in working age Americans, accounting for more than 12,000 new cases in the United States each year. The principle evidenced based treatment for proliferative diabetic retinopathy involves laser-mediated ablation, which fails to alter the molecular pathology of the disease, and as such, nearly half of patients require future treatments. Thus, our overall goal is to identify new targets for intervention at the molecular level that will lead to development of innovative, nondestructive therapies that address treatment of the cause of diabetic retinopathy, rather than the effect. The pathogenesis of this disease is caused by a combination of hyperglycemia and a reduction in insulin mediated signaling, which results in diabetic neurovascular complications through the induction of structural and physiological changes in the retina. The research proposed in this application is innovative, because it represents an entirely different approach to address the molecular basis of diabetic retinopathy, i.e. hyperglycemia-induced alterations in the translational control of gene expression. The central hypothesis is that the addition of O- linked N-Acetylglucosamine (O-GlcNAcylation) to serine or threonine residues of translation initiation factors mediates a shift from cap-dependent to cap-independent mRNA translation, resulting in an altered gene expression pattern that contributes to the pathophysiology of diabetic retinopathy. The hypothesis is supported by findings of elevated flux of glucose through the hexosamine biosynthetic pathway and O-GlcNAcylation of key components of the mRNA cap-binding complex, including eIF4E binding protein 1, eIF4G, eIF4A, and poly(A)-binding protein, under conditions of diabetes-induced hyperglycemia. Furthermore, herein we provide preliminary evidence that hyperglycemia favors the translation of mRNAs with internal ribosome entry sites, such as those encoding key vascular growth factors, in a manner that is dependent on the disruption of eIF4F complex assembly. During the mentored phase, the PI will acquire technical expertise from the laboratory of Dr. Gerald Hart on the methodology used to identify O-GlcNAcylation sites in proteins that control mRNA translation. Once the modified sites have been identified, the mechanisms through which hyperglycemia impairs eIF4F complex assembly will be defined. The mentored phase will also provide time for the candidate to receive guidance from Dr. Thomas Gardner to evaluate if preventing disruption of eIF4F complex assembly is sufficient to inhibit early preclinical phases of the pathogenesis of this disease in a mouse model of diabetes. With respect to outcomes, this project is expected to not only expand the PI's skills and systems of analysis, but will also identify novel mechanisms that link the metabolic abnormalities associated with diabetes to enhanced vascular growth factor expression in the retina. Identification of such mechanisms is significant because it is expected to validate new targets for the development of preventive and/or therapeutic interventions aimed at addressing the molecular basis of diabetic retinopathy and promoting healthy vision.

描述（由申请人提供）：糖尿病性视网膜病是美国人失明的主要原因，每年在美国占12,000多个新病例。该原理对增生性糖尿病性视网膜病的基于基于的治疗涉及激光介导的消融，这未能改变该疾病的分子病理，因此，将近一半的患者需要将来的治疗。因此，我们的总体目标是确定在分子水平上进行干预的新靶标，这将导致创新，无损疗法的发展，这些疗法解决糖尿病性视网膜病因的治疗方法，而不是影响。该疾病的发病机理是由高血糖和胰岛素介导的信号降低的结合引起的，这通过诱导视网膜的结构和生理变化而导致糖尿病神经血管并发症。本应用程序中提出的研究具有创新性，因为它代表了一种完全不同的方法 解决糖尿病性视网膜病的分子基础，即高血糖诱导的基因表达转化控制的改变。中心假设是，添加O-连接的N-乙酰葡萄糖胺（O-Glcnacylation）与翻译起始因子的丝氨酸或苏氨酸残基介导了从依赖CAP依赖性的mRNA转换到依赖CAP的mRNA翻译，从而导致基因表达模式改变了糖尿病的病理学杂物症的病理学。通过六胺生物合成途径的葡萄糖通量升高以及mRNA帽结合复合物的关键成分的O-Glcnacylation的发现，该假设得到了支持，包括EIF4E结合蛋白1，EIF4G，EIF4G，EIF4A，EIF4A和POLY（A） - 结合蛋白质，在糖尿病下的条件下。此外，我们提供了初步证据，表明高血糖有利于内部核糖体进入位点的mRNA的翻译，例如编码关键血管生长因子的mRNA，以依赖于EIF4F复合体组装的破坏方式。在指导阶段，PI将从Gerald Hart博士的实验室中获取有关用于识别控制mRNA翻译的蛋白质O-Glcnacylation位点的方法。一旦确定了修改的位点，高血糖会损害EIF4F复合物组件的机制。指导阶段还将为候选人提供时间从托马斯·加德纳（Thomas Gardner）博士获得指导，以评估是否防止EIF4F复合体组装破坏足以抑制小鼠模型中该疾病发病机理的早期临床前阶段 糖尿病。关于结果，预计该项目不仅会扩大PI的技能和分析系统，而且还将确定与糖尿病相关的代谢异常与增强视网膜血管生长因子的增强的机制。这种机制的识别非常重要，因为预计将验证旨在解决糖尿病性视网膜病的分子基础并促进健康视力的预防和/或治疗干预措施的开发的新目标。