Lecture 19 - Recombinant DNA technology Flashcards
DIABETES
Type 1
Type 2
NZ Type 1
1:5000
childhood onset
NZ Type 2
15% lifelong risk
What are recombinant DNA technologies?
Joining bits of DNA together (some from different species).
Insert into organism to produce (express) a useful protein.
recombinant DNA technologies examples
Fluorescent jellyfish
Take DNA (green fluorescent protein) from jellyfish and place inside fly
what are critical elements for recombinant DNA technologies?
Plasmids
Plasmids
• circular pieces of double stranded DNA
• Replicate independently of
the host’s chromosomal
DNA
• Provide a benefit to hosts
e.g. antibiotic resistance
• Common in bacteria, but
also found in eukaryotes.
Key components of recombinant DNA plasmids
Origin of replication (ORI)
Antibiotic resistance gene
Promoter
Origin of replication (ORI)
allows initiation of replication using host DNA polymerase
Antibiotic resistance gene
allows selection of cells containing plasmid.
Promoter
Drives expression of your favorite gene (e.g. insulin or GFP) in cells with appropriate transcription factor.
Promoter needs to
change to allow expression in.
Bacteria (prokaryote)
Fish (Eukaryote)
Neurons (cell type specific)
Cutting and pasting DNA into plasmids
Restriction enzymes
Ligases
Restriction enzymes
- found in bacteria – defense system to degrade foreign DNA
* Cut dsDNA at specific sequences
DNA Ligases
- Complementary base pairing
* Catalyses formation of phosphodiester bond to repair nick in DNA backbone