Abstract
Replication and its control in lambda are reviewed in the framework of the replicon hypothesis. The experiments and arguments presented here give evidences that: (1) the N product acts in replication only by controlling the levels of the O and P products. (2) The O product controls positively theis replicon at the initiation step. (3) A new mutant, tiny 12, demonstrates that the replicator is a single structure and allows a high-resolution mapping of it. (4) Replication at an early stage is bidirectional, The characteristic linear polymer DNA molecules found at the late stage are discussed. (5) Transcription of the x-o-p region stimulates the initiation process not by leading to the synthesis of a protein, but by modifying the structure or cellular location of the replicates.
