Molecular mechanisms of recovery of stalled DNA replication fork

点击翻译按钮获取中文摘要

Using oriC plasmid DNA replication in vitro, we analyzed molecular mechanisms recovering the stalled replication fork. We found that a translesion DNA polymerase, Pol IV, readily catalyzed a bypass DNA synthesis at a DNA lesion placed on leading or lagging strand DNA and that the replication fork progression was resumed by this bypass DNA synthesis. We demonstrated that Pol IV rapidly (<15 sec) obstructs the stable interaction between Pol III^* and the beta clamp (the lifetime of the complex >5min), causing the removal of Pol III^* from template DNA. Our study suggests a model in which the interaction between Pol III^* and the beta clamp is mediated by Pol IV to ensure that DNA replication proceeds with minimal interruption.