1. You are a molecular biologist working at a biotech company. Your CEO has identified an untapped niche market — Canadian bachelor farmers — and thinks the company can make millions
developing new crops to sell to them. Your assignment is to develop, for the pickle industry, frost resistant cucumbers that glow fluorescent green so they are easy to find in the dark (short days in
northern Canada, you know). You have identified the Northern cod as a fish species that produces the appropriate anti-freeze protein (AFP). You are also able to buy a plasmid from BioRad
Laboratories containing the gene from a jellyfish species that produces a glowing fluorescent protein (GFP). You obtain Arctic cod and raise them in an aquarium in the lab. Your first step is to make a
genomic DNA library from the cod. Describe this process. Be specific!
2. Now you want to find the AFP gene in this cod genomic DNA library. Although the genome of the Arctic cod has not been sequenced, from careful study of GenBank, the online database of
DNA sequences, you are able to create a probe for the AFP gene from other arctic fish species. Explain what a probe is, and describe how you will use this to isolate the AFP gene from the
DNA library. Be specific!
3. You have now isolated the bacterial colony which contains the plasmid with a DNA fragment that includes the cod AFP gene. As a research control, you need to double check the size of
that cod DNA fragment. Describe a procedure for cutting out the cod DNA fragment from the plasmid and measuring its size.
4. Once you isolate the bacterial colony containing the plasmid with the cod AFP gene, you need to combine this gene with the jellyfish GFP gene on a single plasmid. As is standard practice in
the biotech industry, the GFP plasmid has a multiple cloning site and a selectable marker. Describe this cloning process. Be specific!
5. Research is going well! You are now working on overcoming the obstacle of getting your recombinant plasmid into the pickling cucumbers and getting high expression of both AFP and
GFP. Unfortunately, one night someone breaks into your lab and steals your most promising prototype cucumber seedlings. Your company’s security force calls in the CSI New York team
and they find a single hair follicle at the crime scene. How will they use this to find the thief? Be specific!