Transformation vs Transfection
Transformation and transfection are two simple techniques used to introduce a foreign gene into a host cell. However, these techniques depend on the type of host or vector systems.
What is Cell Transformation?
Transformation is the technique employed to introduce genes into yeast and bacterial cells. This technique usually causes heritable changes in genes, and thus the expression of the gene is permanent. The bacterial transformation was first introduced in 1928 by Frederick Griffith. Then in early 1970s, this technique was used in E. coli. During the process of transformation of E. coli, the cells are soaked in ice-cold solution of CaCl2. This step makes E.coli cells competent. After that, the competent cells are mixed with the plasmid DNA and are incubated on ice for 20-30 min. Then a short heat shock is given in order to enable the transfer of DNA into the cell. Finally, the cells are placed in a nutrient broth and incubated at 37 °C for 60-90 min in order to establish the plasmids. Once these steps are successfully completed, the transformed cells can be placed on a suitable media for propagation of cells. Since, transformation is considered as an inefficient technique, it may not be used for preparation of clone banks.
What is Cell Transfection?
Transfection is a method of introduction of a foreign gene, usually, into mammalian cells. There are two methods of transfection; namely, transient transfection and stable transfection. In transient transfection, gene expression is available for a limited time; thus, the alteration of gene causes temporary expression. This transfection method is simple and fast; hence it can be used routinely. One drawback of transient transfection is the difficulty of applying for large scale protein synthesis systems.
During stable transfection, a target gene is integrated into the genome of the host cell, and thus the gene expression is permanent, unlike the transient transfection.
What is the difference between Transformation and Transfection?
• Transformation is the introduction of a gene into a prokaryotic cell (bacterial and yeast), whereas transfection is usually called the introduction of a gene into a mammalian cell.
• Transformation results in heritable alteration, in genes, whereas transfection can result in either temporary expression or permanent changes in genes.