Fault tolerance of information processing in gene networks

The major objective of this paper is to study the fault tolerance of gene networks. For single gene knockouts we investigate the disturbance of the communication abilities of gene networks globally. For our study we use directed scale-free networks resembling important properties of gene networks, e.g., signaling, or transcriptional regulatory networks, as well as metabolic networks and define a Markov chain on the network to model the communication dynamics. This allows us to evaluate the spread of information in the network and, hence, detect differences due to single gene knockouts in the gene-to-gene communication asymptotically regarding the limiting stationary distributions governed by the Markov chain. Further, we study the connection of the global effect of the perturbations with local properties of the network topology by means of statistical hypothesis tests.