Hierarchy in the assembly of the Bacillus subtilis replisome in vivo

The regulation of chromosome replication is of critical importance for correct cell-cycle progression and genomic stability. A key protein in bacterial replication initiation is DnaA. This protein is analogous to the eukaryotic origin recognition complex, and also functions as a transcription factor that coordinates cell-cycle and development with replication status. After binding of DnaA to the region of the chromosome called the origin of replication, the other proteins of the replication machinery assemble into a functional complex (replisome) that allows for processive replication. Existing knowledge about the interaction between the various replisome proteins is largely derived from in vitro studies using purified E. coli proteins, and little is known about the temporal requirements and hierarchy in the assembly of the replisome in vivo. The researcher plans to investigate the assembly of the replisome of Bacillus subtilis in vivo using state-of-the-art techniques such as chromatin immunoprecipitation and the user-controlled degradation of tagged proteins. More specifically, the researcher plans to determine which components demonstrate a dependency on other factors to form a functional assembly in vivo.