a two-dimensional simulation model of the bicoid gradient in drosophilabicoid梯度的二维仿真模型在果蝇.pdfVIP

A Two-Dimensional Simulation Model of the Bicoid Gradient in Drosophila Jingyuan Deng1,3, Wei Wang1,4, Long Jason Lu1,3, Jun Ma1,2* 1 Division of Biomedical Informatics, Cincinnati Children’s Hospital Research Foundation, Cincinnati, Ohio, United States of America, 2 Division of Developmental Biology, Cincinnati Children’s Hospital Research Foundation, Cincinnati, Ohio, United States of America, 3 Department of Biomedical Engineering, University of Cincinnati, Cincinnati, Ohio, United States of America, 4 Department of Chemical Engineering, University of Cincinnati, Cincinnati, Ohio, United States of America Abstract Background: Bicoid (Bcd) is a Drosophila morphogenetic protein responsible for patterning the anterior structures in embryos. Recent experimental studies have revealed important insights into the behavior of this morphogen gradient, making it necessary to develop a model that can recapitulate the biological features of the system, including its dynamic and scaling properties. Methodology/Principal Findings: We present a biologically realistic 2-D model of the dynamics of the Bcd gradient in Drosophila embryos. This model is based on equilibrium binding of Bcd molecules to non-specific, low affinity DNA sites throughout the Drosophila genome. It considers both the diffusion media within which the Bcd gradient is formed and the dynamic and other relevant properties of bcd mRNA from which Bcd protein is produced. Our model recapitulates key features of the Bcd protein gradient observed experimentally, including its scaling properties and the stability of its nuclear concentrations during development. Our simulation model also allows us to evaluate the effects of other biological activities on Bcd gradient formation, including the dynamic redistribution of bcd mRNA in early embryo