Integration of Nucleotide Synthesis and DNA Replication in E.coli

对几种细菌的细胞学研究表明，参与DNA复制、修复和染色体凝聚的多种蛋白质在细胞中心高度富集。增加这些蛋白质的局部浓度被认为可以促进DNA复制的进程和效率。从噬菌体感染的细菌细胞到哺乳动物细胞，多种证据表明，有一种多酶复合物参与了脱氧核苷三磷酸（dNTPs）的合成，与DNA复制机制的组成部分有物理关联。虽然这些复合物的耦合不是必需的，但耦合的含义是在复制的活性位点会增加dNTPs的浓度，从而最大限度地提高复制分叉的效率和稳定性。本研究旨在了解必须在空间和时间上控制的过程，以最大限度地提高DNA复制的效率：(i)通过解决核苷酸合成和DNA复制的协调问题；（ii）通过确定构成或与复制体相关的因素，复制体是一种多酶复合物或负责DNA复制的“工厂”。这些研究的一个关键特征是，它们有可能定义与DNA复制相关的蛋白质相互作用网络。了解这些过程对所有细胞都至关重要，因为遗传信息从母细胞到子细胞的忠实和准确的传递对所有生物体都至关重要。此外，失去复制叉稳定性可能导致叉崩溃，导致突变或丧失生存能力。研究生和本科生是本研究项目的关键参与者。

Cytological studies in several bacterial species have shown that multiple proteins involved in DNA replication, repair and chromosome condensation are highly enriched at the cell center. Increasing the localized concentration of such proteins is thought to facilitate the processivity and efficiency of DNA replication. Multiple lines of evidence, from phage infected bacterial cells to mammalian cells, indicate that there is a multi-enzyme complex involved in the synthesis of deoxynucleoside triphosphates (dNTPs), physically associated with components of the DNA replication machinery. Although the coupling of these complexes is non-essential, the implication for coupling is that there would be an increased concentration of dNTPs at active sites of replication, maximizing the efficiency and stability of replication forks. This research is aimed at understanding the processes that must be spatially and temporally controlled to maximize the efficiency of DNA replication: (i) by addressing the coordination of nucleotide synthesis and DNA replication and (ii) by identifying factors that constitute or are associated with the replisome, a multi-enzyme complex or 'factory' responsible for DNA replication. A key feature of these studies is that they have the potential to define the protein interaction network associated with DNA replication. Understanding these processes is of fundamental importance to all cells because faithful and accurate transmission of genetic information from mother cell to daughter cell is crucial in all organisms. Additionally, loss of replication fork stability can lead to fork collapse, resulting in mutation or loss of viability. Graduate and undergraduate students are critical participants in this research project.