Gene Cloning

Gene Cloning

Clone: A group of identical cells or organisms

To clone a gene:

1) Insert the gene into a vector that can carry the into a host cell

2) Ensure that it will replicate there

3) Insertion is carried out by cutting the vector and the DNA to be inserted with the same restriction endonuclease to ensure that both have the same "sticky ends"

Vector for cloning the bacteria come from two major types:

(1) Plasmids, and

(2) Phages

Recombinant DNA Technology

A) It was developed in 1970

B) Procedure:

(1) Obtain DNA from an organism

(2)ADD Restriction enzymes

(3) A reproducible set of fragments

(4)Inset into replicating DNA molecules

(5) This gives Recombinant DNA

(6) Introduce this DNA in appropriate cells

Why clone a gene?

Let's say you have a Genome with GeneA, GeneB & GeneC

Your gene of interest is GeneA, You would

(1) Select the gene of interest

(2) Clone the gene, which could be used for

a) DNA sequence, Protein product expression

b) Gene Therapy

c) Prepare the gene product in large scale

Restriction digestion generates a reproducible set of DNA fragments(?)

Restriction Enzymes:

1) Bacterial Enzymes that recognize a specific 4-8 base pair sequences in double stranded DNA

(2) Cleave both DNA strands at the restriction sites.

(3) Cut the DNA into a reproducible set of

fragments called restriction fragments.

Types of Nucleases

(1) Endonucleases: Make a cut within a DNA molecule

(2) Exonucleases: Digest DNA from the end Types of cuts By Endonocleases:

(A) Sticky