Characterization of Arabidopsis Telomeres

拟南芥端粒的表征

• 批准号: 8905580
• 负责人: Eric Richards
• 金额: $ 9.5万
• 依托单位: Cold Spring Harbor Laboratory
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-07-15 至 1990-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8905580&HistoricalAwards=false
• 关键词: Characterization; Arabidopsis; Telomeres

Telomeres are the specialized structures that form the termini of eukaryotic chromosomes. These structures are essential for the replication and maintenance of the genome. Telomeres have been extensively studied in lower eukaryotes but considerably less in known about higher eukaryotic telomeres. A higher eukaryotic telomere has recently been cloned from the flowering plant Arabidopsis thaliana, providing the opportunity to study the telomeric regions of this organism as a model system. Two aspects of telomere structure and function will be studied. First, the nature and organization of the DNA sequences that lie adjacent to A. thaliana telomeres will be investigated. Second, the mechanism by which a broken chromosome end acquires a new telomere (i.e., telomere healing) will be studied using a chromosomal mutant of A. thaliana which carries a healed telomere. The healed telomere will be isolated and its structure compared to that of the original chromosomal site to determine how the healing event took place. In addition, the healed telomere, which resided proximal to a centromere, will be investigated as a potential tool for studying A. thaliana centromere structure. Characterization of essential structural components of chromosomes gives greater insight into a basic understanding of mechanisms used by cells to maintain the correct chromosome complement. Additionally, this information could be useful in engineering artificial chromosomes for plants, a technique which would add significantly to the already powerful repertoire of available molecular techniques.

端粒是形成真核染色体末端的特殊结构。这些结构对于基因组的复制和维护是必不可少的。端粒在低等真核生物中得到了广泛的研究，但对高等真核生物的端粒知之甚少。最近从开花植物拟南芥中克隆了一个更高的真核细胞端粒，这为研究该生物的端粒区域作为模式系统提供了机会。我们将从端粒结构和功能两个方面进行研究。首先，将研究与拟南芥端粒相邻的DNA序列的性质和组织。第二，染色体断裂末端获得新端粒的机制(即端粒愈合)将使用携带愈合端粒的拟南芥染色体突变体进行研究。修复后的端粒将被分离，并将其结构与原始染色体位置的结构进行比较，以确定愈合事件是如何发生的。此外，修复后的端粒位于着丝粒附近，将被作为研究拟南芥着丝粒结构的潜在工具进行研究。描述染色体的基本结构成分可以更好地理解细胞用来维持正确染色体补充的机制。此外，这些信息可能对为植物设计人造染色体有用，这项技术将显著增加现有强大的分子技术的保留范围。