Abstract

Genexpression that is the cellular synthesis of proteins is comprised of the sub-steps tran- scription (mRNA synthesis based on the DNA master), translation (protein synthesis based on the mRNA) and protein folding. Owing to the large number of interactions between individual components this process is very complex in vivo and therefore mathematical modeling is extremely laborious. By means of simpli�ed in vitro model systems individual aspects of cellular gene expression can be studied in detail. Cell-free gene expression denotes the biochemical synthesis of proteins in vitro. Cell-free systems are comprised of the predominant components of the cellular transcription and translation machinery like polymerases, ribosomes, amino acids and nucleotides dissolved in bu�er. These systems are either cellular extracts or are reconstituted from puri�ed components. In this thesis gene expression in a cell-free system was used to develop a quantitative model system of the gene expression kinetics in vitro. To this end techniques were developed that enable reproducible quantitative fuorescence measurements of mRNA and protein synthesized in a cell-free system.