GENES AFFECTING METABOLISM AND LONGEVITY IN C. ELEGANS

四个数量性状基因座（QTL），通过遗传作图发现和重组缩小，影响成虫寿命和一个或多个压力反应在线虫C。优雅每种菌株与亲本菌株的基因组在遗传上有1-3%的差异，但在这些表型上与亲本菌株存在可重复且显著的差异。另外，目前在C.据报道，突变可以延长寿命， 饮食干预（热量限制和辅酶Q缺乏）显著增加野生型菌株和一些突变体的寿命。我们建议研究这四个新的QTL平行两个修改饮食和“长寿面板”的14个突变株（代表所有类别的突变，赋予1.5- 3.8-tbld寿命延长相对于适当的控制），一系列的措施，表明他们的代谢和抗氧化状态。具体目的是（1）通过选择和测试将它们划分的重组体来缩小所涉及的QTL间隔。（二） 评估每个长寿基因座和长寿突变体和饮食（具有对照）组的多种遗传表型：性状包括对氧化和其他应激的抗性、代谢活性（O2消耗; CO2和NH3的产生）和寿命代谢输出，以及作为热量摄入的函数的寿命。(3)评估这些基因座的分子表型，包括（a）代谢谱，以测量自由基生成和损伤指数（对于同源系和寿命组），以及（B）在微阵列上评估的基因表达谱。 (4)通过以下最终策略评估和确认候选基因的功能：（a）通过转基因过表达或RNAi抑制进行表型逆转，针对转录水平明显不同的等位基因;（B）基于作图，对已知具有长寿等位基因多态性的五个菌株中候选基因的外显子进行测序;（c）对于因转座子插入而不同的等位基因，筛选由精确的种系突变引起的回复突变体。 切除;和（d）通过拯救酵母敲除菌株的功能测定。影响寿命和代谢损伤的遗传变异可能在进化中被保留，因此将在其他模式生物中进行评估。这种比较分子老年学策略可能导致发现影响人类寿命和年龄相关疾病的途径，从而减轻老年人的疾病和衰弱。

Four quantitative trait loci (QTLs), discovered by genetic mapping and narrowed through recombination, affect both adult longevity and one or more stress responses in the nematode C. elegans. Each strain differs genetically from the parental strain by 1-3% of the genome, yet differs from it reproducibly and significantly in these phenotypes. In addition, 47 loci are presently known in C. elegans, at which mutations have been reported to extend life, and two dietary interventions (caloric restriction and CoQ deficiency) markedly increase the life spans of wild type strains and some mutants. We propose to study these four new QTLs in parallel with two modified diets and a "longevity panel" of 14 mutant strains (representing all classes of mutation that confer 1.5- to 3.8-tbld life-extension relative to appropriate controls), for an array of measures indicating their metabolic and antioxidant status. The Specific Aims are to (1) Narrow the implicated QTL intervals by selecting and testing recombinants that partition them. (2) Assess multiple in rive phenotypes for each longevity locus and the panel of long-lived mutants and diets (with controls): traits include rcsistance to oxidative and other stresses, metabolic activity (02 consumption; production of CO2 and NH3) and lifetime metabolic output, and life span as a function of caloric intake. (3) Assess molecular phenotypes of these loci, including (a) metabolic profiles to measure indices of free radical generation and damage (for the congenic lines and also for the longevity panel), and (b) genc-cxprcssion profiles assessed on microarrays. (4) Assess and confirm candidate-gene functions by the following end-game strategies: (a) phenotypic reversion through transgenic overexpression or RNAi suppression, for alleles differing markedly in transcript levels: (b) sequencing exons of candidate gene in five strains known to harbor allelic polymorphisms for longevity based on mapping; (c) for alleles differing by a transposon insertion, screening for revertants that arise by precise germline excision; and (d) functional assay by rescue of yeast knock-out strains. Genetic variants that affect both longevity and metabolic damage are likely to be conserved in evolution, and will therefore be evaluated in other model organisms. This comparative molecular gerontology strategy may lead to discovery of pathways affecting life span and age-associated diseases in humans, and thus to the alleviation of illness and debility among the aged.