2. RECOMBINANT DNA TECHNOLOGY
INTRODUCTION
⚫A recombinant DNA molecule is produced
by joining together two or more DNA
segments usually originating from different
organism.
⚫Achieved by cutting DNA(restriction
enzymes)into suitable fragments and
joining together the appropriate
fragments(ligation).
3. TOOLS OF GENETIC ENGINEERING
A)RESTRICTION
ENDONUCLEASES(RE)
⚫Bacterial enzyme that can cut DNA at
specific sites
⚫Recognition sequences; site in DNA
which is cut by RE.
⚫Cleavage pattern; Form sticky ends
which can easily pair with other DNA
having complementary sticky ends.
⚫Also called as molecular scissors
4.
5. B)DNA LIGASE
⚫Cutted DNA fragments are covalently
joined by this.
⚫Join the fragments by forming
phosphodiester bond between
phosphate group of 5’carbon of one
deoxy ribose with hydroxyl group of
3’carbon of another deoxy ribose.
6.
7. BASIC PRINCIPLES
STEPS IN GENE CLONING
1)Identification and isolation of desired
gene.
2)Insertion of isolated DNA into a suitable
vector
3)Introduction of this vector into suitable
organism
4)Selection of transformed host cells
5)Multiplication/Expression/Integration
followed by expression of the gene
8.
9. APPLICATIONS
Manufacture of proteins/hormones
Interferon, plasminogen activating factor,
blood clotting factors, insulin, growth
hormone,several enzymes etc.
⚫Diagnosis of molecular diseases:
sickle cell anaemia, thalassaemia,
familial hypercholesterolaemia, cystic
fibrosis.
⚫Prenatal diagnosis: DNA from cells
collected from amniotic fluid, chorionic
villi.
10. Gene Therapy:
⚫This is achieved by cloning a gene into
a vector that will readily be taken up &
incorporated into genome of a host
cell.
Application in Agriculture:
⚫Genetically engineered plants are
developed to resist draught &
diseases. Good quality of food &
increased yield of crops is also
possible.
11. REFERENCES
⚫ T.A.Brown.Gene cloning and DNA
analysis.Blackwell publishers;2006(5);302-
322.
⚫ B.D.Singn.Text book of biotechnology.
Kalyani Publishers.;2006(1);11-104.
⚫ U.Satyanarayana and U.Chakrapani.
Textbook of biochemistry.Allied
Publishers.2006(3).578-618.
⚫ Hugo Almeida, Maria Helena Amaral, Paulo
Lobão. Drugs obtained by biotechnology
processing. Brazilian Journal of
Pharmaceutical Sciences;vol. 47;2011.
