Recombinant Gene Expression Protocols: Overview of Experimental Strategies for the Expression of Recombinant Genes

The direct cloning of DNA fragments, either derived from naturally occurring or artificially designed gene sequences, into various cloning vectors, including bacteriophages, plasmids, and viruses, is the cornerstone of modern molecular biology. Such recombinant constructs represent the basic reagents of molecular biology. One of the major applications utilizing cloned DNA sequences is the expression of the cloned DNA into a protein product, i.e., the expression of recombinant genes. Because the cloned DNA sequences can be modified or altered, recombinant expression technology thus enables the investigator to custom-design the final protein product to sun specific requirements. The production of such recombinant gene products is in fact one of the major success stories of modern molecular biology. Thus, in addition to answering fundamental questions related to regulation of gene expression, gene structure and function, and other basic issues of molecular biology, the technology of recombinant genes has revolutionized modern biotechnology and biomedicine. Applications in gene therapy, biopharmaceutics, biopolymers, and the like, have major impacts on science, medicine, agriculture, and industry.