explain Transient transfection - (Sep/15/2010 )
In transfection, foreign DNA is introduced into eukaryotic cells. Experimentally, this is most often done as an instance of transient transfection, in which the transfected gene is expressed only transiently, that is, in only the cell to which it was originally inserted and only for a short period of time. This process is usually used to test how various genetic modifications affect the functioning of particular genes.
In transient transfection, the gene introduced can be lost from the cell at any time depending on environmental factors. At the latest, the transient gene will be lost during cell mitosis; neither daughter cell will retain the transient gene. For a cell's genetic material to retain the gene introduced through transfection, a stable transfection must occur.
Most transfection is accomplished either by microinjection of the foreign DNA into the cell, or through a chemical or biological reagent such as a calcium ion or liposome that creates a "gate" in the cell allowing the uptake of the foreign DNA. 