ABSTRACT
The initial impetus for rDNA technology came about in the early 1970s with the simultaneous development of techniques for the transformation of E. coli, cutting and joining of DNA molecules, and monitoring of the products of cutting and joining reaction. To explain the processes of gene cloning and gene manipulations, understanding of certain basic techniques is essential. This chapter discusses these techniques. Electrophoresis through agarose gels is the standard method for the separation, identification, and purification of DNA and RNA fragments ranging in size from a few hundred to 20 kb. The pulsed field gel electrophoresis technique was conceived by D. C. Schwartz and C. R. Cantor to allow the electrophoretic separation of DNA molecules several megabases in size. In native polyacrylamide gel electrophoresis, proteins are applied to a porous polyacrylamide gel and separated in an electric field.
