SbcCD Regulation and Localization in Escherichia coli

The SbcCD complex and its homologues play important roles in DNA repair and in the maintenance of genome stability. In Escherichia coli, the in vitro functions of SbcCD have been well characterized, but its exact cellular role remains elusive. This work investigates the regulation of the sbcDC operon and the cellular localization of the SbcC and SbcD proteins. Transcription of the sbcDC operon is shown to be dependent on starvation and RpoS protein. Overexpressed SbcC protein forms foci that colocalize with the replication factory, while overexpressed SbcD protein is distributed through the cytoplasm.