adaptive response of a gene network to environmental changes by fitness-induced attractor selection基因网络环境变化的适应性反应fitness-induced吸引子的选择.pdfVIP

Adaptive Response of a Gene Network to Environmental Changes by Fitness-Induced Attractor Selection 1 2 3,5,6 1,3,4 Akiko Kashiwagi , Itaru Urabe , Kunihiko Kaneko , Tetsuya Yomo * 1 Department of Bioinformatics Engineering, Graduate School of Information Science and Technology, Osaka University, Suita, Osaka, Japan, 2 Department of Biotechnology, Graduate School of Engineering, Osaka University, Suita, Osaka, Japan, 3 Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, Japan, 4 Complex Systems Biology Project, Exploratory Research for Advanced Technology, Japan Science and Technology Agency, Osaka University, Suita, Osaka, Japan, 5 Department of Pure and Applied Sciences, The University of Tokyo, Tokyo, Japan, 6 Complex Systems Biology Project, Exploratory Research for Advanced Technology, Japan Science and Technology Agency, The University of Tokyo, Tokyo, Japan Cells switch between various stable genetic programs (attractors) to accommodate environmental conditions. Signal transduction machineries efficiently convey environmental changes to the gene regulation apparatus in order to express the appropriate genetic program. However, since the number of environmental conditions is much larger than that of available genetic programs so that the cell may utilize the same genetic program for a large set of conditions, it may not have evolved a signaling pathway for every environmental condition, notably those that are rarely encountered. Here we show that in the absence of signal transduction, switching to the appropriate attractor state expressing the genes that afford adaptation to the external condition can occur. In a synthetic bistable gene switch in Escherichia coli in which mutually inhibitory operons govern