Translational control of ROS Management

ROS 管理的翻译控制

基本信息

批准号：
9063543
负责人：
Thomas J Begley
金额：
$ 38.73万
依托单位：
SUNY POLYTECHNIC INSTITUTE
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-08-15 至 2019-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9063543
关键词：
Address Affect Anticodon Antioxidants Automobile Driving Biochemical Cancer Model Cell Death Cell Proliferation Cell model Cell physiology Cells Codon Nucleotides Colon Carcinoma Colorectal Cancer Computer Analysis DNA DNA Damage DNA Repair DNA Sequence Alteration Data Down-Regulation Drug Metabolic Detoxication Engineering Enzymes Equilibrium Event Gene Expression Genes Genome Stability Goals Health Human Hydrogen Peroxide Link Lipids Malignant Neoplasms Malignant neoplasm of urinary bladder Mass Spectrum Analysis Measures Messenger RNA Methylation Methyltransferase Modeling Modification Molecular Monitor Mutation Normal Cell Output Oxidative Stress Pattern Positioning Attribute Process Proteins Publishing RNA Reactive Oxygen Species Reading Resistance Resources Ribonucleotide Reductase Selenocysteine Signal Transduction Signaling Protein Solid Neoplasm Stress Substrate Specificity System Terminator Codon Testing Transfer RNA Translations Tumorigenicity Work biological adaptation to stress cancer cell cancer prevention cancer therapy carcinogenesis carcinogenicity disease-causing mutation glutathione peroxidase improved insight novel overexpression prevent programs response thioredoxin reductase tool treatment strategy tumor growth

项目摘要

DESCRIPTION (provided by applicant): Both environmental and endogenous processes generate pathologically high levels of ROS, with subsequent damage to lipids, proteins and DNA promoting mutation and cell death. However, low levels of ROS are physiologically important in regulating cell proliferation and gene expression.1,2 Cells must thus prevent the detrimental and promote the beneficial aspects of ROS, which suggests that there are precise regulatory strategies to maintain proper ROS levels. We propose to test the hypothesis that cells manage ROS balance by turning-on and turning-off the translation of ROS detoxification and DNA damage response proteins, using the opposing activities of the RNA methyltransferases ALKBH8 and TRM9L. The underlying mechanism arises from our discovery that enzyme-catalyzed methylation signals by ALKBH8, operating at the level of tRNA modification to anticodons, can translationally up-regulate selenocysteine (Sec)-containing ROS management proteins. These RNA modifications are required for "stop-codon recoding" - the mechanism of reading internal stop-codons as Sec-codons in mRNAs for Sec-containing glutathione peroxidases (GPXs, antioxidants) and thioredoxin reductases (TrxRs, regulate ribonucleotide reductase activity to promote the DNA damage response). We hypothesize that dueling RNA modifications control stop-codon recoding to promote (ALKBH8) or prevent (TRM9L) the translation of Sec-proteins and thus regulate ROS and DNA damage responses. Further, we hypothesize that part of the process of carcinogenicity involves hijacking of RNA modification systems to turn-off stress responses and promote a pro-mutagenic program of ROS-induced DNA damage and decreased DNA repair. To facilitate our studies, we have developed a modification analysis platform to monitor 33 human tRNA modifications and we have demonstrated that anticodon modifications are significantly regulated in response to ROS stress. Together with our RNA modification analysis platform, we will use biochemical, molecular and computational analyses to test our hypothesis in a robust set of normal, cancer- derived and engineerable lines. Importantly, our studies will define a novel system of translational control of stress response, dissect the mechanism a pro-mutagenic program, and reveal new targets and strategies for cancer treatment and prevention.

描述（由申请人提供）：环境和内源过程都会产生病理学上高水平的 ROS，随后对脂质、蛋白质和 DNA 造成损害，从而促进突变和细胞死亡。然而，低水平的 ROS 在调节细胞增殖和基因表达方面具有重要的生理意义。1,2 因此，细胞必须防止 ROS 的有害方面并促进其有益方面，这表明存在精确的调节策略来维持适当的 ROS 水平。我们建议使用 RNA 甲基转移酶 ALKBH8 和 TRM9L 的相反活性来测试细胞通过打开和关闭 ROS 解毒和 DNA 损伤反应蛋白的翻译来管理 ROS 平衡的假设。潜在的机制源于我们的发现，即 ALKBH8 的酶催化甲基化信号，在反密码子的 tRNA 修饰水平上运行，可以翻译上调含有硒代半胱氨酸 (Sec) 的 ROS 管理蛋白。这些 RNA 修饰是“终止密码子重新编码”所必需的，该机制将内部终止密码子读取为 mRNA 中的 Sec 密码子，用于含 Sec 的谷胱甘肽过氧化物酶（GPX，抗氧化剂）和硫氧还蛋白还原酶（TrxR，调节核糖核苷酸还原酶活性，以促进DNA 损伤反应）。我们假设双重 RNA 修饰控制终止密码子重新编码，以促进 (ALKBH8) 或阻止 (TRM9L) Sec 蛋白的翻译，从而调节 ROS 和 DNA 损伤反应。此外，我们假设致癌过程的一部分涉及劫持 RNA 修饰系统以关闭应激反应并促进 ROS 诱导的 DNA 损伤和 DNA 修复减少的促突变程序。为了促进我们的研究，我们开发了一个修饰分析平台来监测 33 种人类 tRNA 修饰，并且我们已经证明反密码子修饰在 ROS 应激反应中受到显着调节。与我们的 RNA 修饰分析平台一起，我们将使用生化、分子和计算分析在一组强大的正常、癌症衍生和可工程细胞系中检验我们的假设。重要的是，我们的研究将定义一种新的应激反应转化控制系统，剖析促突变程序的机制，并揭示癌症治疗和预防的新目标和策略。