1. TRANSFECTION OF ANIMAL CELLS
Ekta
Msc.Biotechnology(3rd sem)
Roll no. - 201628
Submitted to - Dr. Ram Gopal

2. TRANSFECTION
● Transfection is a method of transporting DNA , RNA and/or various
macromolecules into an eukaryotic cell by using chemical , lipids or
physical based methods.
● Cells that have incorporated the foreign DNA are called transfectants.
Transformation - genetic alteration of bacteria by the direct uptake and
incorporation of exogenous DNA from their surroundings.
Transduction - virus transfers genetic material from one bacterium to
another.

3. PURPOSE/USES OF TRANSFECTION
● Study gene function
● Study protein expression
● Transfer DNA into embryonic stem cells

5. CALCIUM PHOSPHATE CO-PRECIPITATION
● DNA is mixed with calcium chloride
● Addition to buffered saline / phosphate
solution and incubating at room
temperature
● Formation of DNA - calcium phosphate
coprecipitates which adhere to surface of
cells
● Uptake presumably by endocytosis or
phagocytosis
● Precipitate must be formed freshly at the
time of transfection

6. ELECTROPORATION
● Uses an electric pulse to create
temporary pores in cell
membranes.
● Most critical parameter is the
intensity and duration of
electrical pulses.

7. LIPOFECTION
● Used to inject genetic material into a cell by means
of liposomes.
● Electrostatic interactions between the positive
charges of cationic lipid head groups and the
negatively charged phosphates of the DNA
backbone are the main forces that allow DNA to
spontaneously associate with cationic lipids.
● When liposomes encounter nucleic acids they re-
form into nucleic acid lipid complexes called
lipoplexes.
● An overall net positive charge of the complex
allows closer association of the complex with the
negatively charged cell membrane.
● Entry of the liposome complex into the cell via.
Endocytosis

8. VIRAL VECTORS
● DNA can also be introduced into cells using viruses as a carrier, the technique is
called transduction.
● Transgene may be incorporated into viral vectors either by addition to the whole
genome or by replacing one or more viral genes.This can be done by ligation or
by homologous recombination.
● If the transgene replaces a none essential gene the vector is will be helper-
independent , if it replaces an indispensable gene , then this vector will be helper
dependent.
Advantages of such vectors
● High capacity for foreign DNA
● Because no viral gene products are made , the vector has no intrinsic cytotoxic
effects.

10. MICROINJECTION
● A technique of delivering foreign DNA into
a living cell.
● Through a glass micropipette
● Introduced DNA may lead to the over or
under expression of certain genes.
● Micropipette tip of 0.5 mm diameter.
● This method is limited to ex vivo
applications.

11. REFERENCES
https://en.wikipedia.org/wiki/Transfection
https://www.promega.in
https://www.slideshare.net/

12. THANK YOU