Modeling and control of the protein synthesis process in eukaryotic cells

Protein synthesis is an essential process of cell cycle and growth in eukaryotic cells. The initiation stage of the translation process is known to be the most crucial in regulation of gene expression. This paper presents a reduced model of the initiation process using the eukaryotic initiation factor (eIF)-2 unit and proposes methods to control it. Linearization of the model is presented as a measure to simplify the analysis and the control applications. The properties of the linear model were investigated and compared to the nonlinear model. It was shown that the linear model is (marginally) stable and a linear controller was introduced to regulate the production level of protein. A nonlinear state feedback control was also applied in order to increase production of protein in a controlled manner. In both linear and nonlinear models, the rate of protein synthesis can be regulated using a specific factor as an intracellular input, and by means of measurement techniques available today. The density of the ribosomes on the mRNA can then be set to a desired level. If this strategy can be implemented de facto, then a genuine control on protein synthesis process can be obtained.