Creative Expression: Mammalian Expression Vectors and Systems

Date: February 2, 1998

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Prokaryotic expression systems, reviewed in the September 1, 1997, issue of The Scientist were part of the early repertoire of research tools in molecular biology. Although the expression of recombinant protein in prokaryotes provided a means to develop other research tools (antibodies, for example ) and study basic aspects of biological function, the scope and depth of this research were limited, especially with regard to eukaryotic proteins. The de novo synthesis of recombinant eukaryotic proteins in a prokaryotic system imposed a number of detrimental constraints on the eukaryotic gene product. Among the two most critical were improper protein folding and assembly, and the lack of posttranslational modification, principally glycosylation and phosphorylation. Prokaryotic systems do not possess all the appropriate protein synthesizing machinery to produce a structural and/or catalytically functional eukaryotic protein.

To overcome this hurdle, a new technology was developed that utilized...