|MadSci Network: Molecular Biology|
Hello Hina! Did you know that there already are transgenic plants which glow?! The glow-in-the-dark genes come from sources such as fireflies, jellyfish and phosphorescent bacteria. As pretty as they may be, plants have not been modified to glow-in-the- dark for aesthetic reasons. Phosphorescent genes have been introduced into plants as "reporter genes". Scientists put new genes into a plant with the hopes of improving various qualities. The gene is attached to a "vector" which should be able to slip into the plant cell and get carried along as a part of the cell's DNA. If all works well, the gene will be treated as though it were always a part of the cell's genome. However, this does not always happen. The vector may not be able to get into the cell, or may be stopped by the cell's defense system. In order to locate the successfully transformed cells, a second gene is attached to the first one. This second gene will produce something that can be easily observed. One typical product is an antibiotic resistance; only transformed cells will grow when the antibiotic is added to the cells. This second gene is called a "reporter gene". Instead of antibiotic resistant reporter genes, some scientists have started using phosphorescent reporter genes. The genes taken from the firefly and bacteria are the luciferase enzymes. When these enzymes break down the substrate luciferin, light is produced. The genes taken from jelly fish are called green fluorescent proteins. These genes need a blue light (or UV light) and calcium in order to glow in the dark. So to summarize, the "glow-in-the-dark" gene and another gene are attached to a vector which is introduced into a plant cell. The vector should insert the genes into the cell genome. When a plant grows from the cell, adding the right substances (light and calcium or luciferin) will cause the plant to glow in the dark. I hope this helps you in answering your friend's question! Thanks for asking! Evelyne
This photo of a plant containing the luciferase enzyme is from the website: http://kazza.cia.com .au/website/luciferase.html For some nifty photos of plants with the green fluorescent protein inserted, see this site: http://www.oardc.ohio- state.edu/plantranslab/gfp.htm Here are a list of web references that I used: Dr. Haseloff and his lab, Background on Green Fluorescent Protein http://w ww.plantsci.cam.ac.uk/Haseloff/GFP/GFPbackgrnd.html "Shedding light on how jellyfish glow" Diedtra Henderson , Seattle Times science reporter http://seattletimes.nwsource.com/news/health- Science/html98/jell_071498.html "FAQ for Green Fluorescent Protein (GFP)", Gayle Callis HT,HTL(ASCP)MT Veterinary Molecular Biology, Montana State University, Bozeman, MT 59717-3610 http://www.histology.to/GFPfaq.h tml "Video Imaging of Regulated Firefly Luciferase Activity in Transgenic Plants and Drosophila" Steve A. Kay - Andrew J. Millar, Kenneth W. Smith, Shawn L. Anderson NSF Center for Biological Timing Department of Biology Gilmer Hall University of Virginia Charlottesville, VA 22901 Christian Brandes, Jeffrey C. Hall NSF Center for Biological Timing Department of Biology Brandeis University Waltham, MA 02254 http://www.promega .com/pnotes/49/2788d/2788d.html "Plant Transformation by Lux+ Agrobacterium" Anna Szenthe and William J. Page Department of Biological Sciences M-341 Bio Science Bldg. University of Alberta Edmonton, Alberta T6G 2E9 http://www.zoo.utoronto.ca/able/volumes/vol-19/07-szenthe/07- szenthe.htm
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