DNA Damage/Repair and Cell Death

DNA 损伤/修复和细胞死亡

• 批准号: 6927467
• 负责人: LEE J MARTIN
• 金额: $ 30.09万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-04-01 至 2010-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6927467
• 关键词: DNA damage; DNA repair; apoptosis; biological signal transduction; cell age; cell death; cerebral cortex; cysteine endopeptidases; developmental neurobiology; embryo /fetus tissue /cell culture; fluorescent in situ hybridization; gene expression; laboratory mouse; mitogen activated protein kinase; neural degeneration; p53 gene /protein

DESCRIPTION (provided by applicant): Neuronal cell death induced by DNA damage has been implicated in the pathogenesis of many acute and chronic neurological disorders in humans, and DNA damage-induced cell death is a fundamental principle driving therapy for many types of cancer. The major goal of the experiments in this grant proposal is to determine if DNA damage is a cause or consequence of neurodegeneration. Cultured embryonic mouse cortical neurons will be used as a model to study cause-effect links between specific types of DNA lesions and cell death and the mechanisms of DNA damage-induced apoptosis in young and mature neurons. In Specific Aim 1 we will identify lethal levels of DNA damage in neurons and the relationships between DNA damage level, DNA lesion type, and cell death pattern (apoptosis, necrosis, or hybrid) and will test the hypothesis that toxicity of DNA damaging agents on neurons is maturation-related. We will study if DNA damage occurs preferentially at specific sites within the neuronal genome using comet-FISH analysis. We will identify the major DNA repair and DNA degradation pathways in cortical neurons and will determine whether DNA repair is different in neurons at different stages of maturation. We will test the hypothesis that the dependence of DNA damage-triggered death on caspases and MARK signaling differs in neurons of different maturational states. In Specific Aim 2, we will evaluate upstream mechanisms that link DNA damage to downstream apoptosis mechanisms in cortical neurons. We will test the hypothesis that DNA damage-induced apoptosis in young and mature neurons is mediated by the ATM-p53 or cAbl-p53 signaling networks. In Specific Aim 3, we will determine if enforced expression of DNA repair enzymes that function in base excision repair can be neuroprotective. These experiments will provide important information on the toxicity of DNA damage in neurons, the specific types of DNA damage that can occur in neurons, the effects of DNA damage on neurons of different ages, and the molecular mechanisms that transduce DNA damage signals to apoptotic pathways in neurons. This work is relevant to human disease because it will contribute to the understanding of the pathobiology of DNA damage-induced neurodegeneration and to the identification of possible molecular targets for reducing the toxic and neurologic side-effects of cancer therapy.

描述（由申请人提供）：DNA损伤引起的神经元细胞死亡与人类许多急性和慢性神经系统疾病的发病机理有关，而DNA损伤诱导的细胞死亡是许多类型的癌症的基本原理驱动治疗。该赠款建议中实验的主要目标是确定DNA损伤是神经变性的原因或结果。培养的胚胎小鼠皮质神经元将被用作研究特定类型的DNA病变与细胞死亡之间的因果关系的模型，以及DNA损伤诱导的年轻和成熟神经元的凋亡的机制。在特定目的1中，我们将确定神经元中DNA损伤的致命水平以及DNA损伤水平，DNA病变类型和细胞死亡模式（凋亡，坏死或杂交）之间的关系，并将测试DNA损伤剂对神经元的毒性的假说与神经元的毒性成熟。我们将使用彗星 - 鱼类分析研究是否在神经元基因组的特定部位优先进行DNA损伤。我们将确定皮质神经元中主要的DNA修复和DNA降解途径，并确定在不同成熟阶段的神经元中DNA修复是否不同。我们将检验以下假设：DNA损伤触发的死亡对胱天蛋白酶的依赖性和标记信号在不同成熟态的神经元中有所不同。在特定目标2中，我们将评估将DNA损伤与皮质神经元中下游凋亡机制联系起来的上游机制。我们将测试以下假设：DNA损伤诱导的年轻和成熟神经元的凋亡是由ATM-P53或CABL-P53信号网络介导的。在特定目标3中，我们将确定在基础切除修复中起作用的DNA修复酶的强制表达是否可以是神经保护性的。这些实验将提供有关神经元中DNA损伤的毒性的重要信息，神经元中可能发生的DNA损伤的特定类型，DNA损伤对不同年龄的神经元的影响以及将DNA损伤信号传递到神经元中凋亡途径的分子机制。这项工作与人类疾病有关，因为它将有助于理解DNA损伤引起的神经退行性的病理生物学，并鉴定出可能减少癌症治疗的毒性和神经系统副作用的可能分子靶标。