Genetics/Cell Biology of Anoxia in C.elegans

描述(由申请人提供)：极端缺氧是几种涉及心脏和肺功能障碍的疾病的病理中心。缺氧在实体肿瘤对放射或化疗的抵抗中也起到了作用。了解耐缺氧生物对缺氧的遗传和细胞反应，将有助于开发抢救受损的缺血组织或破坏缺氧的肿瘤细胞的治疗方法。我们发现线虫能够在长时间的缺氧(&lt；.001kpa氧气)中存活。胚胎暴露在缺氧环境中会导致细胞周期和发育进程完全停止。一旦再次暴露在氧气中，这些过程就会恢复。这项研究的长期目标是描述线虫对缺氧的分子和细胞反应。这一应用的中心假设是，胚胎包含一个遗传程序，以协调细胞分裂等生物过程的停止，以应对缺氧。以前，我们发现纺锤体检查点是胚胎在缺氧过程中阻止中期卵裂球发育所必需的。我们将结合遗传和细胞生物学技术，进一步研究线虫胚胎缺氧和细胞分裂停滞之间的途径，以期达到以下目的。目的1.检测纺锤体检查点组件在缺氧条件下对胚胎的反应。以前我们发现纺锤体检查点组件(SAN-1和MDF-2)是胚胎缺氧存活所必需的。我们将使用基因和细胞生物学技术来扩展这一发现。目的2.利用RNA干扰技术识别胚胎发育所不需要的基因，但这些基因是胚胎在缺氧状态下存活所必需的。细胞生物学技术将被用来确定这些基因产物是否是卵裂球在缺氧时阻止细胞周期所必需的。

DESCRIPTION (provided by applicant): Extreme oxygen deprivation is central to the pathology of several diseases involving cardiac and pulmonary dysfunction. Oxygen deprivation also plays a role in the resistance of solid tumors to radiation or chemotherapy treatment. Understanding the genetic and cellular response oxygen-deprivation resistant organisms have to anoxia, hypoxia will facilitate the development of treatment for the rescue of damaged ischemic tissue, or the destruction of oxygen deprived tumor cells. We found that the nematode C. elegans is capable of surviving prolonged exposure to anoxia (<.001 kPa Oxygen). Embryos exposed to anoxia leads to a complete arrest of cell cycle and developmental progression. Upon reexposure to oxygen, these processes are resumed. The long-term goal of this research is to characterize the molecular and cellular responses nematodes have to oxygen deprivation. The central hypothesis of this application is that embryos contain a genetic program to coordinate the arrest of biological processes such as cell division in response to anoxia. Previously, we found that the spindle checkpoint is required for embryos to arrest blastomeres in metaphase during exposure to anoxia. We will use a combination of genetic and cell biological techniques to further investigate the pathway between oxygen deprivation and cell division arrest in the nematode embryo by pursuing the following aims. Aim 1. Examine the response the spindle checkpoint components have in embryos exposed to anoxia. Previously we found that the spindle checkpoint components (san-1 and mdf-2) are required for embryos to survive anoxia. We will use genetic and cell biological techniques to expand on this finding. Aim 2. Use RNA interference to identify genes that are not required for embryo development, but are required for embryos to survive anoxia. Cell biological techniques will be used to determine if these gene products are required for blastomeres to arrest the cell cycle in response to anoxia.