DYNAMICS OF THE GENETIC REGULATORY NETWORK FOR ARABIDOPSIS-THALIANA FLOWER MORPHOGENESIS

We present a network model and its dynamic analysis for the regulatory relationships among 11 genes that participate in Arabidopsis thaliana flower morphogenesis. The topology of the network and the relative st rengths of interactions among these genes were based from published ge netic and molecular data, mainly relying on mRNA expression patterns u nder wild type and mutant backgrounds. The network model is made of bi nary elements and we used a particular dynamic implementation for the network that we call semi-synchronic. Using this method the network re aches six attractors; four of them correspond to observed patterns of gene expression found in the floral organs of Arabidopsis (sepals, pet als, stamens and carpels) as predicted by the ABC model of flower morp hogenesis. The fifth state corresponds to cells that are not competent to flowering, and the sixth attractor predicted by the model is never found in wild-type plants, but it could be induced experimentally. We discuss the biological implications and the potential use of this net work modeling approach to integrate functional data of regulatory gene s of plant development. (C) 1998 Academic Press