A number of bacterial and viral genes take part in the decision between lysis and lysogenisation in temperate bacteriophages. In the case of the bacteriophage lambda, at least 5 viral regulatory products (CI, Cro, CII, N and CIII) and several bacterial genes are involved (see [1] for an excellent overview).
We focus here on the logical modelling developed in [2]. As in this paper, for the sake of explanation clarity, we proceed in two steps. We present a model of the core of the lambda regulatory network, constituted by the cross-regulation between the regulatory genes CI (encoding the repressor) and Cro (see phage2.zginml). In a second step, we propose a four element model (see phageLambda4.zginml), encompassing the roles of the regulatory genes CII and N in addition of CI and Cro.
Note that in [3], we considered a modified version of the four component model: phage4 (alternate).zginml. This paper deals with the Petri net representation of logical models. The versions of the two and four component models of the phage lambda switch are available in the form of Petri nets (INA format).
References
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- . 1995. Dynamical behaviour of biological regulatory networks--II. Immunity control in bacteriophage lambda.. Bulletin of mathematical biology. 57(2):277-97.
- . 2008. Petri net modelling of biological regulatory networks. Journal of Discrete Algorithms. 6(2):165-177.