Research Starter Grant: Analysis of ODS-1 in C. elegans Exposed to Anoxia

研究启动资助：分析暴露于缺氧的线虫中的 ODS-1

• 批准号: 0307491
• 负责人: Pamela Padilla
• 金额: $ 5万
• 依托单位: University of North Texas
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-06-01 至 2004-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0307491&HistoricalAwards=false
• 关键词: Research; Starter; Grant; Analysis; ODS

Oxygen deprivation influences the growth and development of organisms. Many organisms in nature are subjected to changes in oxygen levels and have adapted to survive oxygen deprivation. The soil nematode Caenorhabditis elegans is capable of surviving a wide range of oxygen levels and the developmental progression of the organism depends on the oxygen concentration. For example, C. elegans exposed to a hypoxic environment (0.5% to 1.5% oxygen) develop slowly, but nematodes exposed to an anoxic environment (0% oxygen) arrest in their developmental and cell cycle progression. This arrest, anoxia-induced suspended animation, is reversible upon re-exposure to oxygen. Organisms other than C. elegans, such as zebrafish, brine shrimp, and fruit flies are also capable of surviving anoxia by arresting development. Little is known about the developmental and cell cycle arrest in response to anoxia. To gain a full understanding of anoxia-induced suspended animation it is necessary to understand the genetic, physiologic, and cellular responses to anoxia in a variety of metazoans at different stages of development.Embryos exposed to anoxia arrest developmental and cell cycle progression. It is not known if there is a genetic and cellular basis for anoxia induced cell cycle arrest. Using a genetic model system such as C. elegans to study anoxia induced cell cycle arrest will help determine if there is a genetic response to anoxia. C. elegans is a model system in which classical forward and reverse genetic analysis is possible. The large size and transparency of nematode embryos make them an excellent system for observing cell cycle events during early development. Additionally, C. elegans chromosomes are holocentric, with kinetochores that extend the length of the chromosomes. Thus, during anaphase chromosomes move as entire units without lagging arms. Furthermore, the large size of C. elegans kinetochores (up to 4 microns) make it easy to study cell cycle events. Thus, the recent finding by Dr. Padilla that the nematode embryo arrests cell cycle progression in anoxia, make the nematode a useful system for understanding the cellular and genetic responses required for oxygen deprivation survival.Dr. Padilla's long-term research goal is to determine the mechanisms employed by C. elegans to respond to severe oxygen deprivation. The hypothesis of this one-year project is that a gene (ODS-1), identified by an RNA interference (RNAi) screen for genes that are essential for C. elegans embryos to survive anoxia, is a component of the spindle checkpoint in the nematode embryo. The research will focus on the characterization of ODS-1, and consists of the following two aims:Aim 1. To determine the subcellular localization of ODS-1 protein in embryos exposed to a normoxic or anoxic environment.Aim 2. To evaluate the phenotype of ODS-1 (RNAi) embryos.This research will result in the characterization of a gene and gene product that appears to be important for nematode embryos to survive anoxia, and will permit the testing of the hypothesis that spindle checkpoints are involved in anoxia-induced cell cycle arrest.Broader impacts: This is a Research Starter Grant, awarded to an NSF Postdoctoral Fellow who has accepted a tenure-track position at an eligible institution, as described in NSF 00-139. Dr. Padilla actively integrates research and education by recruiting undergraduate and graduate students to work on research projects in her lab, as well as by teaching in the undergraduate classroom.

缺氧会影响生物体的生长和发育。自然界中的许多生物体都会受到氧气水平变化的影响，并且已经适应了缺氧环境。土壤线虫秀丽隐杆线虫能够在各种氧气水平下生存，并且生物体的发育进程取决于氧气浓度。例如，暴露于缺氧环境（0.5％至1.5％氧气）的线虫发育缓慢，但暴露于缺氧环境（0％氧气）的线虫其发育和细胞周期进程停滞。这种由缺氧引起的假死状态的停止在重新暴露于氧气时是可逆的。除了线虫之外，斑马鱼、丰年虾和果蝇等生物也能够通过阻止发育来在缺氧中生存。 关于缺氧引起的发育和细胞周期停滞知之甚少。为了充分了解缺氧引起的假死，有必要了解不同发育阶段的多种后生动物对缺氧的遗传、生理和细胞反应。暴露于缺氧的胚胎会阻止发育和细胞周期进程。目前尚不清楚缺氧诱导的细胞周期停滞是否存在遗传和细胞基础。使用线虫等遗传模型系统来研究缺氧诱导的细胞周期停滞将有助于确定是否存在对缺氧的遗传反应。 线虫是一个模型系统，可以进行经典的正向和反向遗传分析。线虫胚胎的大尺寸和透明度使其成为观察早期发育过程中细胞周期事件的优秀系统。 此外，线虫染色体是全着丝粒的，具有延长染色体长度的动粒。因此，在后期染色体作为整个单位移动而没有滞后臂。此外，线虫动粒的大尺寸（高达 4 微米）使得研究细胞周期事件变得容易。因此，帕迪拉博士最近发现，线虫胚胎在缺氧条件下阻止细胞周期进展，使线虫成为了解缺氧生存所需的细胞和遗传反应的有用系统。帕迪拉的长期研究目标是确定线虫应对严重缺氧的机制。这个为期一年的项目的假设是，通过 RNA 干扰 (RNAi) 筛选对秀丽隐杆线虫胚胎在缺氧中生存至关重要的基因，鉴定出一个基因 (ODS-1)，该基因是纺锤体检查点的一个组成部分。线虫胚胎。 该研究将重点关注 ODS-1 的表征，并包括以下两个目标： 目标 1. 确定暴露于常氧或缺氧环境的胚胎中 ODS-1 蛋白的亚细胞定位。 目标 2. 评估表型ODS-1 (RNAi) 胚胎的特征。这项研究将得出对线虫胚胎在缺氧条件下存活很重要的基因和基因产物的表征，并将允许测试纺锤体检查点参与缺氧诱导的细胞周期停滞的假设。更广泛的影响：这是一项研究启动补助金，授予已在合格机构接受终身教职的 NSF 博士后研究员，如 NSF 00-139 中所述。 帕迪拉博士通过招募本科生和研究生在她的实验室从事研究项目以及在本科生课堂上教学，积极将研究和教育结合起来。