recombinant dna technology part 2 topics genomic libraries id a specific clone or sequence within a...

RECOMBINANT DNA TECHNOLOGY

PART 2

Topics• Genomic libraries

• Id a specific clone or sequence within a library

• Transgenic plants

• Transgenic animals

• Timely topics

Genomic library contains all of the organism’s genome

Probe design

Bacterial clones and finding desired clone

Probe design

A Final about vectors : There are many

types

• Small vectors

• Large vectors

• Expression vectors

• Viral vectors

Transgenic Mice

transgene

Linear DNA

Non-homologous recombination

Knockout Mice

Phenotype of the knockout mouse gives information on protein function

Homozygous knockout

G418gancyclovir

Applications of DNA technology

• Agriculture

• Drug design

• Genetic testing

• Gene therapy

Genetic Modified Plants: “GM”

Tobacco with luciferase gene from firefly

Transgenic plant

Tumor Inducing Plasmid

Model for making genetically modified (GM) plants

GM crops

• Bt toxin genes (Bacillus thuringensis)

Bt Toxin

Cry toxins and cry genes: damages gut of larvae

GM Plants• Roundup ready plants: herbicide

resistant

• Herbicide known as: Glyphosate

Glyphosate• Enzyme inhibitor

• Prevents amino acid synthesis

• Prevents weed growth

• Environmental concerns

Antisense Technology• 5´   C A U G   3´     mRNA

3´   G U A C   5´     Antisense RNA

Anti-Sense Technology &

FLAVR SAVRTM Tomato

•Anti-sense DNA technology inhibits polygalacturonase (PG)

The Flavr-Savr Tomato• Ripens on the vine

• Preserves firmness and flavor

• Uses anti-sense technology

Cloning of a whole organism: Reproductive Cloning

Somatic Cell Germ Cell

For ex. Mammary cell ovum

SHEEP CELLS

54 27

Somatic Cell Germ Cell

For ex. Mammary cell ovum

How to process begins:

542754

discarded

Now the germ cell contains 54 chromosomes!

• The germ is stimulated “electrically”.

• Cell division in some instances begins.

• Individual is identical to host “DNA” donor.

• Aging affects?

“Was Dolly a sheep in lamb’s clothing?”

Somatic Gene Therapy

Successes• SCIDS (Severe Combined Immunodeficiency

Disease)

• Head and neck cancers

But also failures and controversy