Molecular Genetics of Aging in C elegans

描述(申请人提供)：已鉴定出大量可延长线虫寿命的突变。其中许多物种在进化上是保守的。有一个令人信服的案例，即增强抗逆性与延长寿命有关；然而，这种抗压性背后的特定分子机制大多尚不清楚。同样未知的还有什么类型(S)的抗逆性(抗氧化性损伤、脱氧核糖核酸突变、变性蛋白质重折叠等)。对于延长寿命是最关键的。目前也不清楚应激抵抗的不同组织特异性在多大程度上对延长寿命至关重要。线虫是探索衰老过程中组织特异性的有效系统，因为它是短暂的但多细胞的，可以研究后生动物对压力反应的重要方面，而这在单细胞生物体中是无法探索的。我们打算确定必要的效应器，以及那些足以安装应激反应的效应器。我们提出了一套综合的方法来解决这些问题。我们的一般假设是，抵抗压力的能力是线虫寿命延长机制(S)的必要部分。(我们已经知道，抗压是不够的。)我们之前已经分离出对细胞内产生超氧化物的苯二酚：胡桃仁酮有不同反应的突变体，并证明了一些耐O2胁迫的突变体延长了平均寿命和最长寿命。我们将通过选择更多的抗逆性突变体和使用新的高通量策略识别突变体来扩展这些研究。这些研究还将探讨这些变化是否依赖于已知的调控蛋白，如DAF-16，并将利用基于微阵列的研究来补充突变和RNAi方法，因为它们可以识别基于转录的分析可能遗漏的关键基因和基因产物(例如，热休克因子)。

DESCRIPTION(provided by applicant): Numerous mutations that increase the life span of the nematode Caenorhabditis elegans have been identified. Many of these are evolutionarily conserved. There is a compelling case that increased stress resistance is involved in increased longevity; however, the specific molecular mechanisms underlying this stress resistance are mostly unknown. Also unknown are what type(s) of stress resistance (resistance to oxidative damage, mutations in DNA, refolding of denatured proteins, etc.) are most crucial to increased longevity. It is also unclear to what extent differential tissue-specificity of stress resistance is important for enhanced longevity. The nematode is an efficient system for exploring tissue-specificity during aging because it is short-lived but multicellular, allowing the study of important aspects of metazoan response to stress that cannot be explored in single-celled organisms. We intend to identify necessary effectors, as well as those that are sufficient for mounting a stress response. We propose an integrated set of methods for addressing these issues. Our general hypothesis is that the ability to resist stress is a necessary part of the life-extension mechanism(s) in C. elegans. (We already know that stress-resistance is not sufficient.) We have previously isolated mutants showing altered response to the intracellular superoxide-generating quinone: juglone, and demonstrated that some O2-stress resistant mutants have increased mean and maximal life spans. We will extend these studies both by selecting more stress-resist mutants and by identifying mutants using novel high-throughput strategies. These studies will also address whether these changes are dependent on known regulatory proteins like DAF-16 and will utilize microarray-based studies to complement the mutational and RNAi approaches, as they can identify critical genes and gene products that might be missed by transcription-based analyses (e.g., heat shock factor).