GENETIC ANALYSIS OF HYPOXIC DEATH IN C ELEGANS

线虫缺氧死亡的遗传分析

基本信息

批准号：
7928071
负责人：
C. Michael Crowder
金额：
$ 37.66万
依托单位：
WASHINGTON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-08-01 至 2011-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7928071
关键词：
Acute Address Amino Acyl-tRNA Synthetases Animal Model Arginine-tRNA Ligase Biological Process Caenorhabditis elegans Cause of Death Cell Death Cessation of life Collaborations Complex Consumption Data Drosophila genus Elongation Factor Gene Expression Genes Genetic Genetic Models Goals Hypoxia Injury Learning Lentivirus Vector Literature Mammals Manuscripts Measures Mediating Mediator of activation protein Medical Methods Missense Mutation Mitochondria Modeling Molecular Molecular Chaperones Mus Muscle Cells Mutagenesis Mutation Myocardial Infarction Neuronal Injury Neurons Orthologous Gene Oxidases Oxygen Consumption Pathology Pathway interactions Peptide Initiation Factors Play Process Protein Biosynthesis Proteins Proteolysis RNA Interference Reactive Oxygen Species Resistance Role Small Interfering RNA Stroke Testing Therapeutic Toxic effect Translations United States Universities Washington Whole Organism Work axonal degeneration cancer cell gene discovery genetic analysis genetic manipulation genome-wide insight interest preconditioning promoter relating to nervous system research study response termination factor tool trafficking translation factor

Acute Address Amino Acyl-tRNA Synthetases Animal Model Arginine-tRNA Ligase Biological Process Caenorhabditis elegans Cause of Death Cell Death Cessation of life Collaborations Complex Consumption Data Drosophila genus Elongation Factor Gene Expression Genes Genetic Genetic Models Goals Hypoxia Injury Learning Lentivirus Vector Literature Mammals Manuscripts Measures Mediating Mediator of activation protein Medical Methods Missense Mutation Mitochondria Modeling Molecular Molecular Chaperones Mus Muscle Cells Mutagenesis Mutation Myocardial Infarction Neuronal Injury Neurons Orthologous Gene Oxidases Oxygen Consumption Pathology Pathway interactions Peptide Initiation Factors Play Process Protein Biosynthesis Proteins Proteolysis RNA Interference Reactive Oxygen Species Resistance Role Small Interfering RNA Stroke Testing Therapeutic Toxic effect Translations United States Universities Washington Whole Organism Work axonal degeneration cancer cell gene discovery genetic analysis genetic manipulation genome-wide insight interest preconditioning promoter relating to nervous system research study response termination factor tool trafficking translation factor

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项目摘要

Hypoxic cell death in the form of stroke and myocardial infarction is the largest single cause of death in the United States. The fundamental molecular mechanisms of hypoxic cell death are incompletely understood. Studies in genetically tractable model organisms such as Caenorhabditis elegans and Drosophila have made major advances in the fields of cell death, hypoxia sensing, and adaptation. The proposed work will utilize the powerful genetic tools in C. elegans to explore manipulation of protein synthesis, trafficking, and degradation as a means to control hypoxic cell death. Our specific aims are: (1) Define the mechanisms whereby aminoacyl-tRNA synthetases (aaRS's) and other translational machinery proteins control hypoxic injury. In a screen in C. elegans for mutations that produce hypoxia resistance, we isolated a missense mutation in the rrt- 1 gene, which encodes an arginyl tRNA synthetase, a fundamental protein required for translation. This specific aim proposes a systematic study of translation factors as regulators of hypoxic sensitivity. Through these experiments, we should learn which translation factors are the best candidates to target for hypoxic protection. We will also learn what level of translational suppression is required for hypoxia resistance. Finally, we will learn whether the widely held assumption that translational suppression produces hypoxia resistance by reducing energy consumption is correct or if the mechanism of protection is more complex. (2) Examine the role of unfolded proteins and the unfolded protein response (UPR) in hypoxic injury. Multiple studies primarily with cancer cells have found that hypoxia results in an increase in unfolded proteins that may promote cell death. We have evidence that translational suppression protects from hypoxia by reducing the level or toxicity of unfolded proteins. Using C. elegans genetic tools, we will perform a more extensive examination of how translational suppression, unfolded proteins, and the cellular response to unfolded proteins interact to control acute hypoxic injury. (3) Determine whether the orthologs of the implicated C. elegans genes similarly control hypoxic death of mouse primary neurons. In collaboration with Jeff Milbrandt in the Department of Pathology at Washington University, we will determine whether reducing the expression of genes implicated in specific aims 1 and 2 protect mouse neurons from traumatic and hypoxic injury. These experiments will accomplish two goals: First, determine whether the mouse orthologs of the C. elegans genes play similarly important roles in hypoxic neuronal injury and second, whether these genes can be targeted without baseline neural toxicity. Completion of these aims will provide a more complete understanding of the mechanism whereby translational suppression and the unfolded protein response control hypoxic sensitivity and will determine the feasibility of genetic manipulation of these pathways for hypoxic protection of mammalian neurons.

中风和心肌梗死形式的低氧细胞死亡是最大的死亡原因美国。低氧细胞死亡的基本分子机制尚不完全理解。在遗传上可牵引的模型生物（例如秀丽隐杆线虫和果蝇）的研究中细胞死亡，缺氧感测和适应性领域的重大进展。拟议的工作将利用秀丽隐杆线虫中强大的遗传工具探索蛋白质合成，贩运和降解的操纵作为控制低氧细胞死亡的一种手段。我们的具体目的是：（1）定义的机制氨基酰基-TRNA合成酶（AARS）和其他转化机械蛋白控制低氧损伤。在在秀丽隐杆线虫中筛选出产生缺氧性缺氧的突变，我们在RRT-中分离了一个错义突变 1基因，它编码精氨酸TRNA合成酶，这是翻译所需的基本蛋白质。这具体目的提出了对翻译因子作为低氧灵敏度的调节因子的系统研究。通过这些实验，我们应该学习哪些翻译因素是靶向低氧的最佳候选者保护。我们还将了解缺氧性耐药性需要什么水平的翻译抑制。最后，我们将了解转化抑制会产生缺氧性低的假设是否存在通过减少能源消耗是正确的，或者如果保护机理更为复杂。（2）检查展开的蛋白质和未折叠的蛋白质反应（UPR）在低氧损伤中的作用。多项研究主要是随着癌细胞的发现，缺氧会导致展开的蛋白质增加，这可能促进细胞死亡。我们有证据表明，翻译抑制可以通过降低水平或毒性来保护缺氧展开的蛋白质。使用秀丽隐杆线虫的遗传工具，我们将对如何进行更广泛的检查翻译抑制，展开的蛋白质以及对未折叠蛋白的细胞反应相互作用以控制急性低氧损伤。（3）确定牵连的秀丽隐杆线虫基因的直系同源物是否类似地控制小鼠原发性神经元缺氧死亡。与Jeff Milbrandt在病理学系合作华盛顿大学，我们将确定是否减少与特定目的有关的基因的表达 1和2保护小鼠神经元免受创伤和低氧损伤。这些实验将完成两个目标：首先，确定秀丽隐杆线虫基因的小鼠直系同源物在缺氧性神经元损伤，其次，这些基因是否可以在没有基线神经毒性的情况下靶向。这些目标的完成将为翻译的机制提供更完整的理解抑制和展开的蛋白质反应控制低氧灵敏度，并将确定对这些途径的遗传操纵，用于对哺乳动物神经元的缺氧保护。