title: RNA metabolism during a developmental process. Modeling by Boolean functions and automata theory.
abstract: This work describes a model for simulation of rRNA and polyA(+)mRNA evolution during a developmental process - the wing disc differentiation of an Insect, Pieris Brassicae. The model was constructed in two sections: --a logical section built around a logical network of genetic regulations for RNA synthesis and degradation. We postulated the existence of clock pulses, which act as specific stages of development on parameters determining the accumulation and disappearance of the different RNA classes. A simple model was thus able to account for the complex variations of the studied macromolecules during the differentiation phase. --an analogical section, to account for and calculate the accumulation of terminal gene products. This part of the model was based on essential features of the automata theory. In addition, the relations between clock pulses, biological rhythms and their alteration during diapause are discussed. Diapause and emergence from diapause were included in the above model for RNA metabolism. This model enabled us to compute the time at which particular events take place and the stages of synthesis of the main RNA classes. We evaluated the synthesis and degradation rates of these different classes of molecules. These rates are closely related to those reported by other authors in several differentiation systems. Our model seems applicable to any developmental process in which RNA synthesis exhibits noticeable variations. Although such an approach has seldom been used to interpret macromolecular expressions, its application in the present case allowed us to obtain by a simple computation, complex information on the genetic and biochemical features of RNA molecule regulation.
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D007915:Lepidoptera / Q000235:genetics; D008957:Models, Genetic; D012313:RNA / Q000378:metabolism*; D014921:Wings, Animal / Q000166:cytology
chemical_list: D012313:RNA