Towards universal systems for recombinant gene expression.
Recombinant gene expression is among the most important techniques used both in molecular and medical research and in industrial settings. Today, two recombinant expression systems are particularly well represented in the literature reporting on recombinant expression of specific genes. According to searches in the PubMed citation database, during the last 15 years 80% of all recombinant genes reported on in the literature were expressed in either the enterobacterium Escherichia coli or the methylotropic yeast Pichia pastoris. Nevertheless, some eukaryotic proteins are misfolded or inadequately posttranslationally modified in these expression systems. This situation demands identification of other recombinant expression systems that enable the proper expression of the remaining eukaryotic genes. As of now, a single universal system allowing expression of all target genes is still a distant goal. In this light, thorough experimental screening for systems that can yield satisfying quantity and quality of target protein is required. In recent years, a number of new expression systems have been described and used for protein production. Two systems, namely Drosophila melanogaster S2 insect cells and human embryonic kidney 293 (HEK293) cells stably expressing the EBNA-1 gene, show exceptional promise. The time has come to identify a few well-performing systems that will allow us to express, purify, and characterize entire eukaryotic genomes.
Sørensen
Hans Peter
HP
Danish-Chinese Centre for Proteases and Cancer, Danish National Research Foundation, Aarhus University, Department of Molecular Biology, Gustav Wieds Vej 10C, DK 8000 Aarhus, Denmark. hps@mb.au.dk
D000818:Animals; D002460:Cell Line; D003001:Cloning, Molecular / Q000379:methods*; D004331:Drosophila melanogaster; D019309:Epstein-Barr Virus Nuclear Antigens / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D005822:Genetic Vectors; D006801:Humans; D010843:Pichia / Q000235:genetics; D011994:Recombinant Proteins / Q000096:biosynthesis*
D019309:Epstein-Barr Virus Nuclear Antigens; D011994:Recombinant Proteins; C417029:EBV-encoded nuclear antigen 1