Stochastic Model of Lambda Phage Infection (Lysis)

Description


Control of the outcome of phage lambda infection is one of the best understood regulatory systems. Thieffry and Thomas proposed a logical model to describe the dynamics of the network, which is a bistable switch between lysis and lysogeny. Lysis is the state where the phage will be replicated, killing the host. In other words, if the phage is in lysis, then CRO is active and other genes are repressed.


Variables

node1 = CI
node2 = CRO
node3 = CII
node4 = N

Transition Table and Functions

Click to see the transition table of lambda phage model
Click to see the functions of lambda phage model

Propensity Parameters

0.3 0.7
0.7 0.3
0.9 0.9
0.9 0.9

Initial State

0 0 0 0 (representing the state of the bacterium at the moment of phage infection)

Nodes of Interest

1, 2, 3, 4

Number of States

5

Number of Steps

50

Number of Simulations

100

Key Dynamic Features

Steady States

There is only 1 steady state in the system, which is 2 0 0 0.

Cell Population Simulation

Probability Distribution

Transition Matrix

Click to have the transition matrix of lambda phage model for Lysis

Other examples for Stochastic Discrete Dynamical Systems

Stochastic Model of Lambda Phage Infection (Lysogeny)
Stochastic Model of p53-Mdm2

References

D. Murrugarra, A. Veliz-Cuba, B. Aguilar, S. Arat, R. Laubenbacher "Modeling Stochasticity and Variability in Gene Regulatory Networks" (under review)

Author

Seda Arat

Last Updated

February 2012