Chapter 20

DNA Technology & Genomics

Slide 2 of 14

Biotechnology Terms

Biotechnology Process of manipulating organisms or their components to

make useful products Genetic engineering + tissue/cell culturing technologies

Genetic Engineering Manipulation of genes and genome Insulin & GMO (Genetically Modified Organism)

Recombinant DNA Artificially created DNA Typically, DNA is integrated from another species

Slide 3 of 14

Biotechnology Terms

Gene Cloning Laboratory production of multiple copies of DNA segment Therapeutic cloning – embryonic stem cells

Spinal cord injuries Reproductive (organismal) cloning – Dolly the sheep

Restriction Enzymes Enzymes that cut DNA at specific locations Usually, derived from bacteria Cut sites of DNA = restriction fragments Sticky ends – restriction fragments usually have one end

longer than the other

Slide 4 of 14

Slide 5 of 14

Slide 6 of 14

Cloning is fun!!

5 steps1. Identify & isolate the gene of interest

Involves finding a cloning vector – plasmid or organism used to carry the DNA sequence to be cloned

2. Restriction enzymes cut gene of interest from original site & cut vector’s DNA This ensures matching sticky ends on gene of interest &

vector DNA

Slide 7 of 14

Cloning is fun!! (Page 2)

5 steps3. Form the recombinant plasmid

Recombinant plasmid – plasmid + DNA fragments Sealed together using DNA Ligase Restriction enzymes cut gene of interest from original site & cut

vector’s DNA This ensures matching sticky ends on gene of interest &

vector DNA

4. Get the vector (w/gene of interest) into a host cell Usually involves bacterial transformation

5. Select for cells that have been transformed Identify cells with gene of interest (antibiotic resistance)

Slide 8 of 14

Slide 9 of 14

PCR Polymerase Chain Reaction Thermal cycling Amplification of DNA

3 Steps Denaturation (Heating)

Annealing (Cooling)Primer formation

Extension DNA polymerase adds nucleotides at 3’ end

Slide 10 of 14

Slide 11 of 14

Slide 12 of 14

Slide 13 of 14

Biotechnology Terms (More)

Genomic library Thousands of recombinant plasmid clones Each has a piece of the original genome

cDNA Library Complementary DNA Reverse transcriptase makes cDNA from mRNA

Slide 14 of 14