Identification of Mammalian Genes Promoting Life Extension

促进寿命延长的哺乳动物基因的鉴定

• 批准号: 8554747
• 负责人: Wallace Siu Hung Chick
• 金额: $ 31.21万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-30 至 2017-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8554747
• 关键词: Affect; Aging; Alleles; Animals; Antioxidants; Behavior; Bloom Syndrome; Breeding; Cadmium; Caenorhabditis elegans; Cause of Death; Cell Line; Cell Survival; Cells; Cellular Stress; Characteristics; Cloning; Collection; Communities; Coupled; Deposition; Detection; Development; Disease; Drosophila genus; ES Cell Line; Ethylnitrosourea; Etiology; Exhibits; Fibroblasts; Fostering; Free Radicals; Genes; Genotype; Germ Lines; Germ-Line Mutation; Health; Heating; Heavy Metals; Human; Hydrogen Peroxide; Intervention; Invertebrates; Knock-out; Letters; Libraries; Life; Life Extension; Longevity; Lower Organism; Mammals; Measures; Methodology; Methods; Modeling; Mole Rats; Mouse Strains; Mus; Mutagenesis; Mutant Strains Mice; Mutate; Mutation; Nematoda; Outcome; Oxidants; Oxidative Stress; Oxygen measurement, partial pressure, arterial; Paraquat; Pathology; Pathway interactions; Phenotype; Point Mutation; Procedures; Production; Reactive Oxygen Species; Regulation; Research; Resistance; Resource Sharing; Resources; Science; Sister Chromatid Exchange; Source; Stem cells; Stress; Surrogate Markers; System; Tail; Testing; Yeasts; age related; base; cell type; design; embryonic stem cell; end of life; genetic analysis; genome-wide; helicase; improved; in vivo; innovation; insight; interest; microbial; mouse model; mutant; novel; novel strategies; offspring; pluripotency; repository; resistant strain; response; screening; stressor; success; trait; transmission process; vector

DESCRIPTION (provided by applicant): The close relationship between increased resistance to stress and extended life span has been extensively demonstrated in invertebrates such as yeast, the fruit fly, and C. elegans. Several long-lived mouse mutants are also resistant to multiple forms of stress, including oxidants, UV, and heavy metals. This relationship holds equally true for the exceptionally long-lived naked mole rat. Selection for stress-resistance has been successfully employed as a surrogate marker to identify long-lived mutants in lower organisms. Based on these findings, we have pioneered novel approaches to apply methodology usually only available in microbial systems: using stress resistance as a selectable surrogate marker to generate long-lived mutants in the mouse. We have developed novel strategies to allow mutagenesis and mass selection for stress resistance in mouse embryonic stem (ES) cells and have coupled these to a method wherein these ES cells maintain both the stress resistant phenotype and pluripotency, thus allowing us to generate mouse mutants that are stress- resistant. These new mouse models allow us to critically test the hypothesis that increased cellular stress-resistance slows aging and improves life and health span in mammals. These are valuable models and we have numerous collaborators awaiting access to these strains; letters from five labs are attached to this application. Since the procedure is not limite to previously identified genes and pathways, it allows for unbiased detection of novel genes affecting multi-stress resistance in mice. Several refinements are incorporated in this application allowing us to detect both dominant and recessive mutations and to rapidly identify the mutated gene(s). To carry out these novel high-throughput strategies we have constructed novel transposon vectors and will generate a genome-wide library of multi-stress resistant mutant mice. We screen for mutant ES cell clones that are resistant to paraquat and we screen these for multi-stress resistance, levels of reactive oxygen species under stress, pluripotency, expression levels of Nrf2 and other antioxidant genes, and their capability of maintaining stress-resistance after differentiation into other cell types. The gene-trapped alleles conferring stress-resistance are easily identified and verified. A collection of stress- resistant ES cell clones are thus generated and will be deposited in the public cell repository as shared resources. We will generate strains of mouse mutants from these cells for in vivo studies of aging in the mouse. The impact of increased cellular stress-resistance on life span, gross development, general behavior, end-of-life pathology, and age-related diseases will be examined. Importantly, the causative gene(s) for life span extension will also be validated; these genes and pathways are potential targets for pharmacological intervention to slow aging and ameliorate multiple diseases of aging in humans. In summary, the success of these studies will identify new genes implicated in stress-resistance and perhaps modulating mammalian life span and health. We anticipate that the insights gained from these studies will foster a variety of new directions for aging research.

描述（由申请人提供）：抗应激能力增强与寿命延长之间的密切关系已在酵母、果蝇和秀丽隐杆线虫等无脊椎动物中得到广泛证明。一些长寿的小鼠突变体还能够抵抗多种形式的压力，包括氧化剂、紫外线和重金属。对于寿命特别长的裸鼹鼠来说，这种关系同样成立。抗逆性选择已成功用作替代标记来识别低等生物中的长寿命突变体。基于这些发现，我们开创了应用通常仅在微生物系统中可用的方法的新方法：使用抗逆性作为可选择的替代标记来在小鼠中产生长寿的突变体。我们开发了新的策略来允许小鼠胚胎干（ES）细胞中的应激抗性的诱变和大量选择，并将这些与这些ES细胞保持应激抗性表型和多能性的方法结合起来，从而使我们能够产生应激抗性的小鼠突变体。这些新的小鼠模型使我们能够严格检验这样的假设：细胞抗应激能力的增强可以减缓哺乳动物的衰老并延长寿命和健康寿命。这些都是有价值的模型，我们有许多合作者正在等待获得这些菌株；本申请附有来自五个实验室的信件。由于该程序不限于先前确定的基因和途径，因此它可以公正地检测影响小鼠多重应激抵抗力的新基因。此应用程序中包含了一些改进 使我们能够检测显性和隐性突变并快速识别突变基因。为了实施这些新颖的高通量策略，我们构建了新颖的转座子载体，并将生成多重应激抗性突变小鼠的全基因组文库。我们筛选对百草枯具有抗性的突变型 ES 细胞克隆，并筛选它们的多重应激耐受性、应激下的活性氧水平、多能性、Nrf2 和其他抗氧化基因的表达水平，以及分化为其他细胞类型后维持应激耐受性的能力。具有抗逆性的基因捕获等位基因很容易识别和验证。一系列抗应激 ES 细胞克隆 由此生成并将作为共享资源存放在公共单元存储库中。我们将从这些细胞中产生小鼠突变体品系，用于小鼠衰老的体内研究。将检查细胞抗应激能力的增强对寿命、总体发育、一般行为、临终病理学和年龄相关疾病的影响。重要的是，寿命延长的致病基因也将得到验证；这些基因和途径是药物干预的潜在目标，可减缓人类衰老和改善多种衰老疾病。总之，这些研究的成功将鉴定出与抗应激有关的新基因，并可能调节哺乳动物的寿命和健康。我们预计从这些研究中获得的见解将为衰老研究开辟各种新方向。