Complex Systems

A Model of Gene Expression and Regulation in an Artificial Cellular Organism Download PDF

Paul J. Kennedy
Electronic mail address:
Department of Software Engineering,
Faculty of Information Technology,
University of Technology, Sydney,
PO Box 123 Broadway NSW 2007 Australia

Thomas R. Osborn
The NTF Group, Decision Support Consultants,
Level 7, 1 York Street, Sydney NSW 2000 Australia


Gene expression and regulation may be viewed as a parallel parsing algorithm---translation from a genomic language to a phenotype. We describe a model of gene expression and regulation based on the operon model of Jacob and Monod. Operons are groups of genes regulated in the same way. An artificial cellular metabolism expresses operons encoded on a genome in a parallel genomic language. This is accomplished using an abstract entity called a spider. A genetic algorithm is used to evolve the simulated cells to adapt to a simple environment. Genomes are subjected to recombination, mutation, and inversion operators. Observations from this experiment suggest four areas to explore: dynamic environments for the evolution of regulation, advantages of time lags inherent in the expression algorithm, sensitivity of our genomic language, and noncoding regions on the genome. Issues relating to the application of the expression model to evolutionary computation are discussed.