Replication Fork Repair

项目摘要 复制分叉修复对于细胞存活和遗传物质的稳定是必不可少的。在人类身上， 修复效率低下与癌症倾向、神经、免疫学、 发育缺陷和过早衰老。对于微生物病原体来说，修复DNA的能力 损伤是细菌病原体生存所必需的，并促进基因变化，从而 导致抗生素耐药性和感染的持久性。 我们研究的长期目标是更完整地从机械上理解修复 复制分叉及其如何影响基因组稳定性。这将通过使用基因 大肠埃希氏菌系统，其生理机制已为人熟知。一个核心的兴趣是如何 细菌细胞发出信号表明复制困难，以促进修复，以及这是如何与 细菌生长的其他方面。通过生化和遗传分析，这项工作将阐明 新发现的一种保守的DNA解旋酶蛋白YoaA是如何与复制体相互作用的 克服复制过程中的障碍。这项研究将专门讨论RNA的影响 转录和DNA蛋白质复合体对复制和基因组不稳定性的影响 机制被用来克服复制和转录机制之间的冲突。 还将探索由严格饥饿蛋白SSPA控制的调控途径 了解它如何影响DNA新陈代谢。 因为所有细胞通过进化相关的途径以基本相似的方式修复DNA， 这些使用微生物模型生物的研究应该揭示适用于修复的机制 人类细胞中的DNA。此外，因为微生物病原体的DNA损伤反应 在毒素产生、抗生素耐药性和感染持久性方面发挥作用，这项工作可能 为传染病的治疗提供重要的新信息。

Project Summary Replication fork repair is essential for cell survival and stability of genetic material. In humans, inefficiency of repair is associated with cancer proneness, neurological, immunological, developmental defects and premature aging. For microbial pathogens, the ability to repair DNA damage is required for survival of bacterial pathogens and promotes genetic change that can contribute to antibiotic resistance and persistence of infection. The long-term goal of our studies is a more complete mechanistic understanding of the repair of replication forks and how it affects genomic stability. This will be accomplished using the genetic system of Escherichia coli, whose physiology is well understood. A central interest is how bacterial cells signal difficulties in replication to facilitate repair and how this is integrated with other aspects of bacterial growth. By biochemical and genetic analysis, this work will elucidate how a newly discovered conserved DNA helicase protein, YoaA, interacts with the replisome to overcome barriers in replication. This study will specifically address the influence of RNA transcription and DNA protein complexes on replication and genomic instability and what mechanisms are used to overcome conflicts between replication and transcription machinery. The regulatory pathway controlled by stringent starvation protein, SspA, will also be explored to discover how it impacts DNA metabolism. Because all cells repair DNA in fundamentally similar ways by evolutionarily related pathways, these studies using microbial model organisms should reveal mechanisms applicable to repair of DNA in human cells. In addition, because the DNA damage response in microbial pathogens plays a role in toxin production, antibiotic resistance and persistence of infection, this work could provide new information important for the treatment of infectious disease.