The simulation of gene knock-out in scale-free random boolean models of genetic networks

This paper describes the effects of perturbations, which simulate the knock-out of single genes, one at a time, in random Boolean models of genetic networks (RBN). The analysis concentrates on the probability distribution of so-called avalanches (defined in the text) in gene expression. The topology of the random Boolean networks considered here is of the scale-free type, with a power-law distribution of outgoing connectivities. The results for these scale-free random Boolean networks (SFRBN) are compared with those of classical RBNs, which had been previously analyzed, and with experimental data on S. cerevisiae. It is shown that, while both models approximate the main features of the distribution of experimental data, SFRBNs tend to overestimate the number of large avalanches. © American Institute of Mathematical Sciences