The function of DnaA protein as a replisome organizer in the initiation of DNA replication is reviewed. A model is presented showing the construction of two basic types of DnaA-dependent replication origin. New data demonstrate that the dnaA box-DnaA protein complex is a transcription terminator. Only one orientation of the dnaA box results in termination of transcription. Mutation of the dnaA box within the dnaA reading frame shows that DnaA-mediated transcription termination has a role in the autoregulation of the dnaA gene.