DNA BASE EXCISION REPAIR IN PLASMODIUM FALCIPARUM

恶性疟原虫 DNA 碱基切除修复

• 批准号: 6371036
• 负责人: Theodore F Taraschi
• 金额: $ 32.3万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-05-01 至 2006-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6371036
• 关键词: DNA repair; Escherichia coli; Plasmodium falciparum; endonuclease; enzyme activity; molecular cloning; phosphoester ligase; protozoal genetics; recombinant proteins

DESCRIPTION: (provided by the applicant): DNA replication and repair, processes that are essential for cellular proliferation and the maintenance of genome integrity, have gone largely unexplored in parasitology. The replication and control of DNA repair in Plasmodium falciparum are likely to have a number of differences from the mammalian cell. The rapid replication as trophozoites mature into schizonts and the three rounds of replication that microgametes accomplish in 10 minutes at exflagellation are both unusual. For this reason, a basic understanding of these processes in the parasite is an important goal. Our groundbreaking investigations revealed that Plasmodium falciparum (Pj) has DNA repair capabilities, and that the removal of uracil and the repair of abasic sites in DNA are exclusively by a long-patch base excision repair (BER) pathway, which is remarkably different from mammalian cells. Important quantitative differences between the enzymology of the BER pathway in P. falciparum and mammalian cells have been established. The short-term goal of this proposal is to define the fundamental reaction of BER in Plasmodium falciparum. The essential proteins in the parasite BER pathway have been identified and the over expression of the enzymes in bacteria will facilitate their biochemical characterization. These enzymes include Pf AP endonuclease, Pf flap endonuclease (Pf FEN-1) and Pf DNA ligase. Expression of these enzymes is part of our plan to reconstitute the entire parasite BER pathway for studying the individual contributions of each of the key enzymes to the long-patch repair process. A reconstituted BER system will afford future study of the various protein-protein interactions, mechanisms, associations and biochemical reactions under controlled situations of BER. The ultimate goal of these studies is to identify the Plasmodium excision repair genes, determine their biological and biochemical function and assess their role in maintaining the parasite genome. Completion of the proposed aims in this project will provide important, new information about a neglected area of parasite biology, and possibly the opportunity to exploit differences in DNA repair between P. falciparum and mammalian cells to develop new strategies for antimalarial therapy.

描述：（由申请人提供）：DNA复制和维修，过程 对于细胞增殖和维持基因组至关重要 诚信，在很大程度上没有探索寄生虫学。复制和 恶性疟原虫中DNA修复的控制可能具有许多 与哺乳动物细胞的差异。快速复制作为滋养体 成熟成schizonts和微型组的三轮复制 在十分钟的时间内完成，两者都不寻常。因此， 对寄生虫中这些过程的基本理解是一个重要目标。 我们开创性的调查表明，恶性疟原虫（PJ）具有 DNA修复功能，并去除尿嘧啶和修复 DNA中的abasic位置仅通过长块基础切除修复（BER） 途径，这与哺乳动物细胞有很大不同。重要的 P.中BER途径的酶学之间的定量差异。 恶性菌和哺乳动物细胞已经建立。短期目标的 该建议是定义BER在疟原虫中的基本反应 恶意。寄生虫途径中的必需蛋白质已经 鉴定并在细菌中酶的过度表达将有助于 他们的生化特征。这些酶包括PF AP核酸内切酶， PF瓣核酸内切酶（PF FEN-1）和PF DNA连接酶。这些酶的表达 是我们重新建立整个寄生虫途径的计划的一部分 研究每种关键酶对 长距离维修过程。重构的BER系统将提供未来的研究 各种蛋白质蛋白质相互作用，机制，关联和 BER受控情况下的生化反应。最终目标 这些研究是确定疟原虫切除修复基因，确定 它们的生物学和生化功能，并评估它们在维持的作用 寄生虫基因组。完成该项目的拟议目标的完成将 提供有关被忽视的寄生虫生物学领域的重要新信息， 并且可能有机会利用P.之间的DNA修复差异。 恶性菌和哺乳动物细胞开发新的抗疟疾策略 治疗。