Biotechnology: Manipulating Genes This is a no-frills PowerPoint for the basic foundational information for the bacterial transformation simulation activity. Please modify as appropriate for your class! Suggestion: preview the overall concept of “biotechnology” to students. Inform them that over the course of this week they will walk through a simulation of how we take genes from one organism and literally insert them into a different species! If your class will be doing the actual fluorescent protein bacterial transformation lab, preview that as well.

1950s: DNA Structure Chargaff: A + G = T + C Rosalind Franklin’s X-ray Watson & Crick: double helix This should be review for students. In the 1950s, Watson & Crick outlined the structure of DNA, illuminated by the x-ray picture taken by Rosalind Franklin, showing the double helix structure. This understanding opened the door to “reading” the As, Ts, Cs and Gs in DNA. Soon after, we were able to “read” bases (A, T, C, G).

1960s: DNA  Proteins Jacob & Monod propose mRNA transcription for getting copies of single genes out of the nucleus. Many scientists contributed to figuring out the “Genetic Code” of tRNA translation. The concepts of transcription and translation should be review for the students. They should have practice with at least one of the two Genetic Code charts pictured. For this activity, students will need to do a translation using the single-letter abbreviations for amino acids (charts provided). Translation graphic is from http://www.nbii.gov/portal/server.pt/community/basic_genetics___cell_biology/401/reading_instructions/561

1970s: Automated DNA Technology Sequencing: Reading the As, Ts, Cs and Gs Synthesis*: Writing the As, Ts, Cs and Gs Human Genome Project: completed in 2003 (* Note: Synthesis of a DNA molecule just makes a DNA molecule – it does not make an entire living cell, nor does it insert that DNA into a living cell. All the same, it is the beginning of being able to actually manipulate (change) DNA.) Now what?

…in 2 people, mice and flies… New York Times article: “Mutation Tied to Need for Less Sleep Discovered”! Actual Study: “We have identified a mutation…that is associated with human short sleep phenotype.” …in 2 people, mice and flies… Even with a “complete” human genome, it’s still difficult to “read” human genes. Once we “finished” mapping the Human Genome, many people expected that full understanding of human genetics would be right around the corner, opening up brave new worlds of gene-based drugs, genetic therapy to cure genetic diseases, increasingly thorough and reliable genetic screening for traits/diseases, etc. But this has been slow going. Here is an example of a recent “discovery” of a gene that sounds exciting in the New York Times article – but actually had a very small (human) scope in the original article. So, yes, we are making discoveries about genes that cause all sorts of traits for all sorts of organisms – but there is much more work to be done for human genetics… From http://www.sciencemag.org/cgi/content/abstract/sci;325/5942/866

Brainstorm Why can’t we just “read” all of an embryo’s genes/traits before (s)he is born?  Article: Twin Study Deepens Multiple Sclerosis Mystery Read the article “Twin Study Deepens Multiple Sclerosis Mystery” (provided as WS.ArticleMSGenetics.docx) as a framework for helping the class to brainstorm why we still can not “read” all of a person’s genes/traits even though we can “read” all the bases in their genome. Some points to make sure are included: We’re still figuring out which proteins do what (nevermind where the genes are that make those proteins). Most human traits are governed by more than one gene. In nearly all eukaryotes, sections of mRNA (introns) get spliced out of the code before it is translated – so we actually can not just look at DNA and figure out the amino acids for all the proteins that get made. There’s so much to sift through! It takes lots of time, lots of people, and lots of money… Even if we could figure out everything that’s in the base sequence of our genome, it turns out the environment plays a huge role too – both through mutation, and also by silencing genes through events like methylation of chromatin.

Applied Genetics Once we identify and sequence genes, we can start manipulating them:

Gene Therapy: Changing a person’s genes to cure their disease From http://stemcells.nih.gov/info/scireport/2006Chapter4.html

Genetically Modified Foods: adding genes to plants to make “super”-crops Pictures from http://www.fehd.gov.hk/english/research_education/heerc/gmf.html, http://www.ifood.tv/b/news/blogs/a2z/5

Production of Pharmaceuticals: Using agriculture to make drugs for diseases Bioengineering on the Farm from http://www.nytimes.com/2009/02/07/business/07goatdrug.html Corn graphic from http://www.foodrenegade.com/gmos-and-pharmaceuticals/

Applied Genetics Once we identify and sequence genes, we can start manipulating them: Gene Therapy Genetically Modified Food Production of Pharmaceuticals NECESSARY FIRST STEP: Find and sequence the proteins & genes for a trait

Simplified Simulation We’re going to simulate a bacterial transformation, in which genes from jellyfish are inserted into bacteria. FIRST STEP: Find and sequence the proteins & genes for a trait

Simplified Simulation Materials for each group: 2 bacterial plasmids (identical) 2 jellyfish genes (different) 1 “Genetic Expression” slip for each gene/plasmid Genetic Code wheel Fill out the “Genetic Expression” slip for each jellyfish gene and for the bacterial plasmid.

Clean Up Did you highlight the genes on the original DNA? Turn in the Genetic Expression slips. Store DNA in Zip-loc for use tomorrow. (Include your names.)