GENETIC DISSECTION OF NATURAL VARIATION IN CALORIC RESTRICTION-INDUCED CELLULAR L

热量限制诱导的细胞 L 自然变异的基因解剖

• 批准号: 8825887
• 负责人: Christopher S Nelson
• 金额: $ 5.42万
• 依托单位: BUCK INSTITUTE FOR RESEARCH ON AGING
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-01 至 2017-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8825887
• 关键词: Age; Aging; Aging-Related Process; Alleles; Behavior; Biochemical; Biological Assay; Biology; Caloric Restriction; Cell Aging; Cell Death; Cell Proliferation; Cells; Chromosome Mapping; Chronic Disease; DNA; DNA Sequence; Data; Diet; Disease; Dissection; Endothelial Cells; Engineering; Environment; Environmental Risk Factor; Future; Gene Expression; Genes; Genetic; Genetic Determinism; Genetic Epistasis; Genetic Polymorphism; Genetic Variation; Genotype; Glucose; Goals; Growth; Human; Individual; Inherited; Intervention; Laboratory Study; Lead; Life; Light; Link; Longevity; Malignant Neoplasms; Maps; Measurement; Measures; Mediating; Metabolism; Methods; Microfluidics; Modeling; Molecular; Molecular Genetics; Mus; Mutagenesis; Mutation; Myelogenous; Nature; Nutritional; Oak Tree; Pathway interactions; Population; Proteins; Quantitative Trait Loci; Rattus; Regulation; Reporter; Research; Role; Signal Transduction; Starvation; Stem cells; Stress; Surveys; System; Techniques; Testing; Validation; Variant; Vascular Diseases; Yeast Model System; Yeasts; aging gene; base; cell age; fitness; fly; genetic analysis; genetic linkage analysis; genetic variant; genome-wide; longevity gene; meetings; novel; novel diagnostics; novel therapeutics; nutrition; overexpression; promoter; public health relevance; reconstruction; research study; response; tool; trait

DESCRIPTION (provided by applicant): Replication and environmental stresses sustained over a cell's lifetime cause damage and ultimately lead to different types of cell death. Understanding the precise molecular mechanisms by which cells age is a major unsolved problem of modern biology. A comprehensive understanding of cellular aging will shed light on chronic diseases such as myeloid cancer and vascular disease, which result from hematopoetic stem cell aging and endothelial cell aging, respectively. Environmental factors have a significant impact on longevity, and one of the best-documented lifespan-extending perturbations is caloric restriction (CR). Yeast, worms, flies, mice, and rats all live longer when reared on CR diets, via a mechanism that remains poorly understood. Genome-scale screens for determinants of the CR response have not been tractable to date; I propose to meet this challenge by harnessing natural genetic variation in the CR response, using wild yeast isolates as a model. My preliminary studies have revealed robust changes between yeast strains in lifespan during CR, including a wild isolate with a distinctly long lifespan under CR conditions. I hypothesize that th genetic determinants of the lifespan extension, growth behavior, and regulatory profile of wild yeast under CR conditions include novel determinants of the CR response. I will test this hypothesis with the following specific aims: Aim 1- I will map the genetic basis of differences between yeast strains in lifespan under CR conditions. Using a panel of genotyped progeny from a cross between two wild yeast isolates, I will assay the lifespan of each with established microfluidic techniques. Statistical-genetic analyses will identify genes and polymorphisms that reproducibly segregate with the lifespan trait, and the role of these factors in lifespan will be validated in independent molecular-genetic experiments. Aim 2- To understand how CR modulates cell proliferation and fitness, I will measure growth traits under CR conditions in the progeny from the cross used in Aim 1, and I will map genetic loci linked to growth behaviors via statistical-genetic methods. Molecular validation of these screen hits will establish genes that mediate the sensing of and response to CR at the cellular level. Comparison to the results of Aim 1 will enable a test of the degree to which lifespan and growth under CR are under shared genetic control. Aim 3- To investigate at a systems level the state of cells grown under CR, I will transcriptionally profile each strain from the cross used in Aim 1. I will map sequence variants that co-inherit with the expression response to CR, and validate these loci in molecular experiments. The results will identify components and connections of the gene network that regulates cell state in response to the nutritional environment, dovetailing with the first two Aim and allowing a genome-scale molecular dissection of growth and longevity decisions during CR.

描述（由申请人提供）：细胞一生中持续的复制和环境压力会造成损害并最终导致不同类型的细胞死亡。了解细胞衰老的精确分子机制是现代生物学尚未解决的主要问题。对细胞衰老的全面了解将有助于阐明分别由造血干细胞衰老和内皮细胞衰老引起的慢性疾病，例如骨髓癌和血管疾病。环境因素对寿命有重大影响，而记录最充分的延长寿命干扰之一是热量限制 (CR)。酵母、蠕虫、苍蝇、小鼠和大鼠在采用 CR 饮食饲养时都寿命更长，但其机制仍知之甚少。迄今为止，对 CR 反应决定因素的基因组规模筛选还不太容易处理。我建议通过利用 CR 反应中的自然遗传变异来应对这一挑战，并使用野生酵母分离物作为模型。我的初步研究揭示了 CR 期间酵母菌株寿命的显着变化，其中包括在 CR 条件下具有明显长寿命的野生分离株。我假设 CR 条件下野生酵母寿命延长、生长行为和调控特征的遗传决定因素包括 CR 反应的新决定因素。我将通过以下具体目标来检验这一假设： 目标 1 - 我将绘制 CR 条件下酵母菌株寿命差异的遗传基础。我将使用来自两种野生酵母分离株杂交的一组基因型后代，通过已建立的微流体技术测定每种酵母的寿命。统计遗传学分析将识别与寿命特征可重复分离的基因和多态性，并且这些因素在寿命中的作用将在独立的分子遗传学实验中得到验证。目标 2 - 为了了解 CR 如何调节细胞增殖和适应性，我将测量目标 1 中使用的杂交后代在 CR 条件下的生长性状，并且我将通过统计遗传方法绘制与生长行为相关的遗传位点。这些筛选结果的分子验证将建立在细胞水平上介导 CR 感知和响应的基因。与目标 1 的结果进行比较将能够测试 CR 下的寿命和生长受共同遗传控制的程度。目标 3-为了在系统水平上研究 CR 下生长的细胞的状态，我将 对目标 1 中使用的杂交中的每个菌株进行转录分析。我将绘制与 CR 表达反应共同遗传的序列变体，并在分子实验中验证这些基因座。结果将确定调节细胞状态以响应营养环境的基因网络的组成部分和连接，与前两个目标相吻合，并允许对 CR 期间的生长和寿命决策进行基因组规模的分子解剖。