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Mark Feltner Skyline High School Dallas, Texas Dr. Alvin Yeh Department of Biomedical Engineering Dr. Arne Lekven Department of Biology Faculty Members Dr. Alvin Yeh • Ph.D., Chemistry, University of California, Berkeley, 2000 • B.S.E., Chemical Engineering, University of Michigan, 1993 Dr. Arne Lekven • Ph.D., 1997, UCLA, Molecular, Cell and Developmental Biology • B.A., 1989, UC San Diego, Animal Physiology. Holly Gibbs, Doctoral Student • B.S., 2006, Texas A&M University • M.Sc., 2008, University of Edinburgh Quick Revisit: The Research 1. Genetically modified zebrafish are grown and bred in the lab. 2. Embryos are treated with selected gene suppressors (morpholino). 3. The embryos develop abnormally. Data Acquisition 4. Using 2-photon spectral microscopy, embryos are laser scanned to view the results of gene ‘knock-downs’ (suppression). Ultrafast laser TPF detector SHG detector Objective TPF, SHG & Light microscopy Relevant TEKS Bio TEKS 4: The student knows that cells are the basic structures of all living things with specialized parts that perform specific functions. Bio TEKS 5: The student knows how an organism grows and the importance of cell differentiation. The student can: (A) describe the stages of the cell cycle, including deoxyribonucleic acid (DNA) replication and mitosis, and the importance of the cell cycle to the growth of organisms; (B) examine specialized cells, including roots, stems, and leaves of plants; and animal cells such as blood, muscle, and epithelium; (C) describe the roles of DNA, ribonucleic acid (RNA), and environmental factors in cell differentiation; and (D) recognize that disruptions of the cell cycle lead to diseases such as cancer. Bio TEKS 6: The student knows the mechanisms of genetics, including the role of nucleic acids. The student is expected to: (A) identify components of DNA, and describe how information for specifying the traits of an organism is carried in the DNA; (B) recognize that components that make up the genetic code are common to all organisms; (C) explain the purpose and process of transcription and translation using models of DNA and RNA; Bio TEKS 7: The student knows evolutionary theory is a scientific explanation for the unity and diversity of life. Classroom relevance: Q: Which aspects of this E3 research are being taught as part of the curriculum in Mr. Feltner’s Biology class? A: Genetics, gene expression, evolutionary conservation of DNA. Also: vertebrate anatomy, embryonic development, ecosystems. Day 1 – Introduction to Zebrafish Students will view live zebrafish in the classroom aquarium. 1. Review of Ecosystems – discuss zebrafish habitat, including food supply, reproduction. 2. Review: tissues, cells, proteins, DNA. 3. Pre-quiz, including engineering-related questions. Day 2 1. Teacher demo. Using projector, students are shown zebrafish brains scans (healthy and mutant), using fluorescent imaging. 2. Team assignments: 3 or 4 students per team. Each team gets a different ‘fish card.’ “Save the Baby Zebrafish!” Hi, my name is Sheldon! I am a new zebrafish embryo. In just 24 hours my brain and spinal cord will be well developed, but you see, one of my genes doesn’t work! I have a genetic disease called “One-eyed Pinhead.” Please find it and fix it before my cells start to multiply! Thanks! BFF (Best Fish Forever), Sheldon P.S.) My protein code is A T T G G A T C T A C C T T G A A C A C A T Using their fish cards, students decipher DNA sequence using Chromosome Chart. Students identify protein name and associated DNA regions using chart and provided tables. Students fill in ‘Gene Table’ provided by teacher. Day 3 • Using data collected in Day 2, each team builds a 3-D model of gene sequence using colored blocks. • Green= protein gene • White = conserved, noncoding regions Red = Polymerase site • Blue = Start & stop codons Day 3, cont’d • To test each team’s model, teacher uses projector to show resulting brain scan images: either mutant or wild type (normal). • If students have misrepresented their genetic construct by getting the blocks in the wrong order, they can rebuild their model and try again. Day 4 1. Classroom discussion comparing students’ genes. 2. Students reconstruct 3-D model of gene and explain to class. 3. Teacher-led discussion: Evolutionarily Conserved Regions of DNA – What does this mean for human medicine? Bioengineering gene therapies? Time permitting, this is a good way to get students more interested: Future Directions/Ethics of Bioengineering: Should their be limits to genetic alteration? Medicine? Who decides? 4. Post-Quiz: Same questions as pre-quiz, Day 1. Students compare pre and post answers. Class discussion. Sample Pre- and Post-Test Questions (open-ended questions): 1. True or False: A change to an organism’s DNA is usually fatal (the organism dies). A. True B. False 2. Which of the following are functions of DNA? A. To pass favorable characteristics to offspring. B. To produce a healthy organism. C. To reproduce itself in the next generation. D. All of the above are functions of DNA. Acknowledgments TAMU E3 RET Program National Science Foundation Nuclear Power Institute Dr. Alvin Yeh Research Group: Tissue Microscopy Lab Dr. Arne Lekven Lab Group Thanks also to the following online sources: Dreamstime.com (color photographs) http://speakingofresearch.com/2011/02/16/a-fish-named- hope/ (zebrafish photograph) http://www.neelscorner.com/zebra-fish-blindness-cure/ (image) http://www.worth1000.com/entries/207979/zebra-fish