Positive autoregulation of cI is a dispensable feature of the phage lambda gene regulatory circuitry.

ABSTRACT: Complex gene regulatory circuits contain many features that are likely to contribute to their operation. It is unclear, however, whether all these features are necessary for proper circuit behavior or whether certain ones are refinements that make the circuit work better but are dispensable for qualitatively normal behavior. We have addressed this question using the phage lambda regulatory circuit, which can persist in two stable states, the lytic state and the lysogenic state. In the lysogenic state, the CI repressor positively regulates its own expression by stimulating transcription from the P(RM) promoter. We tested whether this feature is an essential part of the regulatory circuitry. Several phages with a cI mutation preventing positive autoregulation and an up mutation in the P(RM)

SUBMITTER: Michalowski CB 

PROVIDER: S-EPMC1236637 | biostudies-literature | 2005 Sep

REPOSITORIES: biostudies-literature