LIFESPAN ENHANCING MUTATIONS IN C ELEGANS

延长线虫寿命的突变

基本信息

批准号：
2052882
负责人：
SAMUEL WARD
金额：
$ 18.93万
依托单位：
UNIVERSITY OF ARIZONA
依托单位国家：
美国
项目类别：
财政年份：
1993
资助国家：
美国
起止时间：
1993-08-15 至 1998-07-31
项目状态：
已结题

项目摘要

We recently discovered that sperm production in the nematode Caenorhabditis elegans reduces male lifespan, and that mutations in the spermatogenesis-defective gene, spe-26, can increase average lifespan 35 to 100% (Van Voorhies, 1992, Nature in press). Thus this gene has the largest effect on lifespan of any gene so far identified in C. elegans. The gene has been cloned, and both wild-type and mutant genes have been completely sequenced. This proposal is to extend and utilize these findings to learn more about how sperm production and the spe-26 gene influence aging, and to take advantage of the cloned spe-26 gene to extend life-span by transformation of worms with altered spe-26 clones. C. elegans has many advantages for genetic analysis of the fundamental causes of aging, including short generation time, ease of culture, homozygous wild-type strain, detailed knowledge of its development, sophisticated genetics, small genome with an extensive genetic map and nearly complete physical map, and methods for gene tagging and for DNA transformation. Thus it is well suited for analysis of either Longevity Assurance Genes, that normally act to increase lifespan, or Aging Genes, like spe-26, that must be mutated to increase lifespan. The specific aims of this proposal are as follows. (l) Determine if the lifespan increase caused by spe-26 mutations is mediated solely by their effect on spermatogenesis or if the phenotypes are distinct functions of the same gene. This will be done by characterization of additional mutations and analysis of the sequences responsible for tissue specific gene regulation. (2) Increase the lifespan of wild-type C. elegans by creating transgenic strains that disrupt the normal spe-26 gene by transformation with DNA constructs encoding either spe-26 antisense RNA or dominant negative mutant proteins. This is the most important experiment in terms of the goals of the "Genetic and Molecular Basis of Longevity" program because it would demonstrate that lifespan can be increased by disrupting a normal aging gene in a transgenic animal, a model that could be applied to humans. (3) Find genes similar in function to spe-26 in other organisms by searching for genes similar in sequence. This will be done by low stringency hybridization and PCR amplification with spe-26 primers to see if spe-26 homologues can be found in other animals including mammals. (4) Determine if other mutations affecting spermatogenesis alter C. elegans lifespan. We will take advantage of our laboratory's more than 50 spermatogenesis-defective genes ordered into a developmental pathway to see exactly when during spermatogenesis and under control of which genes does lifespan become reduced. This proposal is directly relevant to human health because fundamental mechanisms of aging may be found and mammalian and human homologues of spe-26 may be identified, and, most importantly, because establishing that lifespan can be increased by transgenic disruption of aging genes will be a model for potential human therapy.

我们最近发现线虫中的精子产生秀丽隐杆线虫降低了男性寿命，并在精子发生缺陷基因SPE-26可以增加平均寿命35 至100％（van Voorhies，1992年，《自然界》中的自然界）。因此，该基因具有迄今为止在秀丽隐杆线虫中鉴定出的任何基因的寿命最大影响。该基因已被克隆，野生型和突变基因均已完全测序。该建议是扩展和利用这些建议研究结果以了解有关精子产生和SPE-26基因的更多信息影响衰老，并利用克隆的SPE-26基因扩展通过改变SPE-26克隆改变蠕虫的寿命。 C 秀丽隐杆线有许多优势用于基本原因的遗传分析衰老，包括短时间，培养的易感性，纯合子野生型压力，对其发展的详细知识，精致遗传学，小基因组，具有广泛的遗传图，几乎完整物理图，以及用于基因标记和DNA转化的方法。因此，它非常适合分析任一寿命保证基因，通常会提高寿命或衰老基因（如SPE-26）必须突变以增加寿命。该提议的具体目的如下。（l）确定SPE-26引起的寿命是否增加突变仅是由于其对精子发生的影响或表型是同一基因的不同功能。这将由表征其他突变和序列的分析负责组织特异性基因调节。（2）增加寿命野生型C.秀丽隐杆线虫通过创造破坏的转基因菌株正常SPE-26基因通过编码的DNA构建体转化 SPE-26反义RNA或显性阴性突变蛋白。这是最重要的实验是根据“遗传和寿命的分子基础”程序，因为它将证明可以通过破坏A中的正常衰老基因来增加寿命转基因动物，可以应用于人类的模型。（3）找到基因通过搜索基因的功能与其他生物中的SPE-26相似序列相似。这将通过低严格的杂交和用SPE-26引物进行PCR扩增，以查看SPE-26同源物是否可以是在包括哺乳动物在内的其他动物中发现。（4）确定其他突变是否影响精子发生改变了秀丽隐杆线虫的寿命。我们会接受的我们实验室的50多个精子发生缺陷基因的优势被命令进入发育途径，以确切查看何时精子发生并在控制哪些基因生命周期的控制下变为减少。该建议与人类健康直接相关，因为可以找到衰老的基本机制和哺乳动物和人类可以确定SPE-26的同源物，最重要的是，因为确定可以通过转基因破坏来增加寿命衰老基因将成为潜在人类治疗的模型。