Replication-fork dynamics

The proliferation of all organisms depends on the coordination of enzymatic events within

large multiprotein replisomes that duplicate chromosomes. Whereas the structure and function

of many core replisome components have been clarified, the timing and order of molecular

events during replication remains obscure. To better understand the replication

mechanism, new methods must be developed that allow for the observation and characterization

of short-lived states and dynamic events at single replication forks. Over the last

decade, great progress has been made toward this goal with the development of novel

DNA nanomanipulation and fluorescence imaging techniques allowing for the direct observation

of replication-fork dynamics both reconstituted in vitro and in live cells. This article

reviews these new single-molecule approaches and the revised understanding of replisome

operation that has emerged.