1 DNA Technology

2 Copying DNA: PCR Polymerase Chain ReactionPolymerase Chain Reaction Gene Amplification A method of making many copies of a piece of DNA

3 PCR: Copying DNA DNA, nucleotides, buffers, “taq” polymerase, and two primers are placed in a small test tube taq polymerasetaq polymerase can work at very high temps

4 PCR: Step 1 DNA is heatedThe DNA is heated (80 o C), the two strands separate PrimersPrimers match with complementary bases Taq pol. begins adding new nucleotides (5’->3’)

5 PCR: Step 2 The tube is cooled the DNA strands together Cycle repeated to make several copies

6 PCR Large amounts of DNA can be made from a small starting sample

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8 Cloning Just a gene vs. whole organims

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10 Bacterial plasmids in gene cloning

11 Cloning a gene Requires: –Plasmid (cloning vector), restriction enzymes, and gene of interest DNA ligase attaches the sticky ends of DNA fragments together Chimeric DNA made!

12 Cloning an organism body cell egg cellA body cell from one organism and an egg cell from another are fused divides like a normal embryoThe resulting cell divides like a normal embryo

13 Cloning “Dolly”

14 Cutting DNA Restriction enzymesRestriction enzymes cut DNA at specific sequences manageable fragmentsUseful to divide DNA into manageable fragments

15 Electrophoresis size and chargeDNA can be separated based on size and charge phosphate groupsnegativelyThe phosphate groups are negatively charged gelelectricityDNA is placed in a gel and electricity is run through

16 Electrophoresis Negative DNANegative DNA moves toward the positive end Smallerfarther and fasterSmaller fragments move farther and faster

17 Electrophoresis