Examining the Role of Exo V in Repairing DNA Damage

检查 Exo V 在修复 DNA 损伤中的作用

• 批准号: 6829440
• 负责人: ANDRES A LARREA
• 金额: $ 3.2万
• 依托单位: UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6829440
• 关键词: DNA damage; DNA repair; SDS polyacrylamide gel electrophoresis; X ray crystallography; affinity chromatography; affinity labeling; bacterial genetics; enzyme activity; exodeoxyribonuclease; exonuclease; genetic recombination; plasmids; predoctoral investigator; protein protein interaction; protein purification; protein structure function; yeast two hybrid system

DESCRIPTION (provided by applicant): Life depends upon the faithful transmission of genetic information from one generation to the next. Unfortunately DNA damage occurs and, when it does, it can lead to the loss of important genetic information. My work focuses on understanding how two different groups of bacteria have chosen to solve the problem presented by one very harmful type of DNA damage: double-strand breaks. The first part of this proposal focuses on RecBCD, which is a heterotrimeric protein from E. coli. RecBCD is a potent double strand 5'-3' and 3'-5' nuclease, helicase, and ATPase. It is highly processive, digesting kilobases of DNA per binding event. It is, however, also a recombinase that promotes homologous recombination. These two paradoxical roles are mediated by the 8-nucleotide chi sequence (5'-GCTGGTGG-3'). The second part of the proposal focuses on AddAB, the two-subunit enzyme responsible for Exo V activity in T. tengcongensis and other gram-positive bacteria. AddAB has the same activity and role in the cell as RecBCD except it responds to a different chi sequence. In this project I will use a variety of techniques including crystallography, genetics, and enzymology to determine the structure and dissect the regulation of these processive nucleases.

描述（由申请人提供）：生活取决于忠实地传播遗传信息从一代到另一代的传播。不幸的是，DNA损伤发生，并且在发生时会导致重要的遗传信息的丧失。我的工作着重于了解如何选择两组不同的细菌来解决一种非常有害的DNA损伤所带来的问题：双链断裂。该提案的第一部分侧重于RECBCD，这是大肠杆菌中的异三聚体蛋白。 RECBCD是有效的双链5'-3'和3'-5'核酸酶，解旋酶和ATPase。每个结合事件都具有高度的方便，消化了DNA的千目标。但是，这也是一种促进同源重组的重组酶。这两个矛盾的作用是由8-核苷酸卡序列（5'-GCTGGTGG-3'）介导的。该提案的第二部分侧重于ADDAB，即tengcongensis和其他革兰氏阳性细菌中负责EXO V活性的两亚基酶。 Addab在细胞中具有与RECBCD相同的活性和作用，除了它对不同的CHI序列响应。在这个项目中，我将使用各种技术在内，包括晶体学，遗传学和酶学来确定结构并剖析这些过程核酸酶的调节。