Host Cell Compatibility in Protein Expression

The expression of cloned genes in prokaryotic or eukaryotic host cells provides the means not only for the study of gene function but also for the production of substantial amounts of protein and nonprotein molecules for commercial and investigational use. In the case of proteins, strategies for determining the most appropriate vector-host combination for the expression of an exogenous gene depend on a diverse range of factors that relate ultimately to the properties of the gene and its product. The approach used in the downstream purification of the product is another factor that impinges on this selection. However, among the most important considerations in the choice of vector and host in ensuring the maximal amount of expression is the compatibility of the host cells to translate the RNA transcript, to ensure the proper folding of the product, and to sustain the protein in the intact and functional state.