Assembly and Dynamics of the DNA Replication Machine

我们体内的细胞携带的遗传信息与我们曾经的胚胎时相同。编码在DNA中，随着我们的成长，信息可靠地从母细胞传递到子细胞数千次。分子机器在细胞内工作，复制和维护这些遗传信息。对这些机器和其他在不同细胞过程中工作的机器的研究，一直受到生物化学的一个主要限制的阻碍：不可能在试管中重建细胞内条件。该提案概述了研究DNA复制的另一种策略，该策略涉及远离体外重建细胞内条件的尝试，而是直接从活细胞中获取相关的生化信息。该实验室的长期目标是通过利用显微镜领域的最新进展，直接从活细胞中提取DNA代谢过程的详细机制见解。而在目前的提案中，候选人将研究DNA复制机器的两个特定方面：其在细胞周期早期的组装和防止其在DNA复制完成之前过早拆卸的机制。这项工作将有助于进一步研究细胞内发生的分子事件的新方法。使用这种方法来研究复制机制的组装和稳定性将为他们的理解提供前所未有的见解。加深对细菌中DNA复制机器的理解将有助于理解在所有其他生物体中类似机器是如何复制和维持染色体的。

Cells in our body carry the same genetic information as that of the embryo we once were. Coded in DNA, the information is reliably transferred from mother to daughter cells thousands of times as we grow. Molecular machines work inside the cells to copy and maintain this genetic information. The study of these machines, and others working in different cellular processes, has been hindered by a major limitation of biochemistry: the impossibility of reconstructing intracellular conditions in test tubes.Outlined in this proposal is an alternative strategy to study DNA replication, one that involves moving away from attempts to reconstruct intracellular condition in vitro and instead obtaining relevant biochemical information directly from living cells. The long-term objective of this laboratory is to extract detailed mechanistic insights on the processes of DNA metabolism directly from living cells by capitalizing on recent advances in the field of microscopy. While in the current proposal the candidate will investigate two specific aspects of the DNA replication machine: its assembly early during the cell cycle and the mechanisms that prevent its premature disassembly prior to the completion of DNA replication.This work will help furthering a novel approach for the study of molecular events happening within cells. Use of this approach to study the assembly and stability of the replication machinery will provide unprecedented insight towards their understanding. Increased comprehension on the DNA replication machine in bacteria will help understanding how similar machines copy and maintain the chromosome in all other organisms.