DNA Technology Activity: Restriction enzymes What is DNA Technology? Its a set of methods Name some of these methods: 1 Cut DNA into segments What cuts the DNA? Restriction enzymes Another method? Gel electrophoresis Why use it? To separate segments 2 Activity: Cloning a gene in bacteria What is done with the segments? Transfer to another organism (E. coli) What are they transferred into in E. coli? A plasmid 3 (also called a ‘vector’ ) What are these ‘new’ plasmids called? Recombinant DNA plasmids 4 What is done with these ‘new’ plasmids? Put back into E. coli 5 E. Coli continues living and dividing But, what new capability does E. coli have? Produces a ‘new’ protein From that gene segment 6 What are the methods used for? Used to study and manipulate genetic material Called? Genetic engineering Or, recombinant DNA technology The basic techniques of genetic engineering have many applications DNA Technology and useful products What was the world’s first genetically engineered pharmaceutical product? Insulin Before modern biotechnology, where did insulin come from? Cows, pigs, horses Why is the genetically engineered insulin better? Its made from a human gene Does not cause allergic reactions Ample supply available What is the name of the technique used to make insulin? Recombinant DNA technology gene A discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA (or RNA, in some viruses) How does the recombinant DNA technique work? A quick look: The gene is inserted into the DNA of another (host) cell The host cell now contains recombinant DNA DNA carrying a gene of interest is taken from a (e.g., a human) cell The host cell multiplies What happens to the DNA? The desired protein is produced recombinant a molecule carrying DNA from more than one organism Humulin production • Huge vats • Liquid culture of bacteria • Bacteria contain insulin gene • And, insulin is produced Insulin collected, purified, tested for quality, packaged Where else is recombinant DNA used? To introduce a gene into crop plants The gene gives resistance to specific herbicides What other crop plants can you think of? e.g., rice, soybeans, cotton Look at the golden rice activity Have you heard about the Flavr Savr tomato? Its been genetically engineered… To reduce rate of spoilage What does this mean? … a marketing advantage It can sit on the shelf longer It can be picked at a later stage of ripeness How is the stone washed denim look achieved? Via genetic engineering… • Recombinant DNA techniques are used • To clone cellulase genes in bacteria • To produce large quantities of cellulase To sell to textile manufacturers What does the enzyme do? It partially breaks down the cotton fibers (They also wear out faster!) Have you ever skied on artificial snow? This is another example of recombinant (r) DNA technology… What has r DNA technology done for skiing? Increase expression of a bacterial protein Called SnowMax Used in snow making machines Mix cold water and protein & huge amounts of snow are produced Activity: Applications of DNA technology Gel electrophoresis What would you do if you needed to analyze the DNA from a crime scene? Collect DNA samples 1 From what? Then what’s next? 2 3 The crime scene itself (1) And any suspects (2, 3) • Extract DNA • Cut &/or amplify the DNA samples What are these fragments called? Restriction fragments Activity: Gel electrophoresis of DNA • Load DNA into wells • Turn on power supply • Watch fragments travel through gel • Observe separated fragments What do you know about DNA to cause the fragments to travel in the gel? - (PO4 ) Length 1 2 1 2 3 3 Compare the results Which DNA sample matches DNA from the crime scene? Do you think this person is guilty of the crime? What is this field of science called? Learning check 1. A recombinant DNA molecule _____. a. is necessary for manufacturing protein on a large scale b. is produced in yeasts c. is the product of a defective gene d. requires DNA from two different individuals-perhaps even individuals from different species e. requires the use of cDNA Learning check 1. A recombinant DNA molecule _____. a. is necessary for manufacturing protein on a large scale b. is produced in yeasts c. is the product of a defective gene d. requires DNA from two different individuals-perhaps even individuals from different species e. requires the use of cDNA 2. This is a DNA fingerprint exhibiting samples from a victim, two suspects, and the crime scene. Which of these DNA fragments is common to both the victim and Suspect 1? A B C D E Activity: DNA Fingerprinting 2. This is a DNA fingerprint exhibiting samples from a victim, two suspects, and the crime scene. Which of these DNA fragments is common to both the victim and Suspect 1? A B C D E 3. This is a DNA fingerprint exhibiting samples from a victim, two suspects, and the crime scene. Which of these DNA fragments is common to both the victim and Suspect 2? A B C D E 3. This is a DNA fingerprint exhibiting samples from a victim, two suspects, and the crime scene. Which of these DNA fragments is common to both the victim and Suspect 2? A B C D E 4. Why is Suspect 1 considered more likely to have committed the crime than Suspect 2? a The crime scene sample contains DNA fragments from both the victim and Suspect 1. b The crime scene sample contains DNA fragments from both the victim and Suspect 2. c Suspect 1 and the victim have more DNA fragments in common that do the victim and Suspect 2. d Suspect 2 and the victim have more DNA fragments in common that do the victim and Suspect 1. e Suspect 1 and Suspect 2 have more DNA fragments in common than either have in common with the victim. 4. Why is Suspect 1 considered more likely to have committed the crime than Suspect 2? a The crime scene sample contains DNA fragments from both the victim and Suspect 1. b The crime scene sample contains DNA fragments from both the victim and Suspect 2. c Suspect 1 and the victim have more DNA fragments in common that do the victim and Suspect 2. d Suspect 2 and the victim have more DNA fragments in common that do the victim and Suspect 1. e Suspect 1 and Suspect 2 have more DNA fragments in common than either have in common with the victim. 5. In gel electrophoresis, DNA molecules migrate from _____ to _____ ends of the gel. a acidic ... basic b negative ... positive c basic ... acidic d long ... short e positive ... negative 5. In gel electrophoresis, DNA molecules migrate from _____ to _____ ends of the gel. a acidic ... basic b negative ... positive c basic ... acidic d long ... short e positive ... negative For Thursday Continue reading chapter 12 More detail on topics covered in Ch 12 For next Tuesday Remember! Exam #2, Tuesday, 11/6 The exam will cover: Chapter 6, Cell Respiration Chapter 7, Photosynthesis Chapter 12, DNA Technology