1. Recombinant DNA Technology ORHow to Mess with DNAfor Fun and
2. ORHow to Make a Mouse Glow in the Dark 3. What the heck is
RecombinantDNA?Recombinant DNA is what you get whenyou combine DNA
from two differentsources.For example: Mouse + Human DNAHuman +
Bacterial DNA Viral + Bacterial DNAHuman + (other) Human DNA(Its
sort of like Frankenstein-DNA!) 4. Why Make Recombinant DNA?
Recombinant DNA Technology May Allow Us To: Cure or treat disease
Genetically modify our foods to increaseflavor, yield, nutritional
value or shelf-life Better understand human genetics Clone cells or
organs 5. Molecular Biologys Best Friends: Bacteria Why use
bacteria? Theyre relatively simple organisms. They reproduce very
quickly and asexually (thismeans that the daughter cells will
contain theexact same DNA as the parent cell). Its pretty easy to
get DNA back into the bacteriaafter youve changed it. We can mess
around with their DNA and kill alot of them during our experiments
and nobodygets mad. ;-) 6. Now for a littlevocabulary 7.
PlasmidsSmall, circular pieces of extraDNA found in bacteria.
Plasmids often carry antibiotic resistance. 8. Restriction Enzymes:
Molecular ScissorsA restriction enzyme (RE) is a specialized
protein thatcuts DNA in a very specific place. Different REs cut at
different places along thenucleotide sequence. 9. Restriction
Enzymes, continued 10. Restriction Enzymes, Cont. Any piece ofDNA
cut witha certainrestrictionenzyme willstick to anyother piececut
with thatsame RE,even if theycome fromdifferentsources. 11. What do
you noticeabout these restrictionsites
(placeswhererestrictionenzymescut)? 12. Cool, but what good are
they?Lets find out 13. Insulin for Diabetics: The Old Way 14.
Insulin for Diabetics: The New Way 15. Step 1: Isolate (find) the
human generesponsible for producing insulin and decide where you
want to put it.In this case, we decide to put our humanDNA into the
plasmid of E. coli, a verycommon bacterium. 16. Step 2: Get the
bacterial (plasmid) DNAout of the E. coli. We do this by basically
exploding them. Step 3:Cut your human DNA and bacterial DNAwith the
same restriction enzyme. 17. Step 4:Mix the cut human DNA, which
contains the insulin gene, with the cut bacterial DNA.Theyll stick
together because they were cut with the same restriction enzyme.
18. Step 5:Get your new recombinantplasmid back into the bacteria.
This is easy because bacteria will take in DNA thats floatingaround
near them. We call this transformation. 19. Step 6 Find the
bacteria that have taken up yourrecombinant plasmid amongst the
riff-raff inthe petri dish. Remember how I said that many plasmids
contain a gene that makes them resistant to antibiotics? How might
you use that to find your special bacteria? 20. Voila!!Now your E.
coli will use its new DNAto make human insulin!Because they
reproduce so quickly, youll soon have thousands, millions, or
billions of human insulin making machines.By filtering out the
bacteria after theyve madeinsulin, youve got clean human insulin
that canbe packaged and given to diabetic patients. YAY! 21. Gene
therapy: another way to use recombinant DNA 22. How do you think
you could makea mouse glow in the dark?Hint: Fireflies have a gene
calledluciferase that makes their little bums light up 23. You can
do itinplants too! 24. What genes do you think wereintroduced to
this poor mouses DNA?