Page 8 - Science Focus (issue 15)

For protein synthesis, the DNA sequence of some with greater brightness of green light
a gene has to be transcribed into messenger emitted, and those that fluoresce different colors
RNA (mRNA), which is then translated into a – like yellow fluorescent protein (YFP), enhanced
polypeptide. Prasher imagined that it would be cyan fluorescent protein (ECFP) [6]. Wait, did you
possible to use tools in molecular biology to insert notice that the colors near the red end of the
the GFP gene right near the gene of interest. The spectrum are missing? Scientists discovered a
cell would then produce a single molecule of red fluorescent protein, mRFP1, from mushroom
fusion protein – the target protein is fused to the anemone Discosoma after the discovery of GFP
GFP – which ideally retains the original functions of [7]. Tsien and other researchers then used the
both proteins. same technique to engineer the red fluorescent
proteins so that variations of different colors, like
Prasher’s idea was made into reality by a
professor in Columbia University, Martin Chalfie, cherry (mCherry) and orange (mOrange), are
available [6]. This complete rainbow of fluorescent
and his wife Tulle Hazelrigg. Chalfie and his proteins allows scientists to label multiple target
team were the first to incorporate GFP into other proteins simultaneously.
organisms. He first managed to express GFP in
bacteria Escherichia coli, which produced a The potential applications of fluorescent
beautiful green pattern when grown on an agar proteins are enormous! It has now become regular
plate. He then succeeded to light up a small practice to study the function and activity of
number of neurons in the transparent nematode countless proteins, especially those implicated
Caenorhabditis elegans, by expressing GFP for certain diseases. The true importance and
in them. Hazelrigg employed her husband’s potential of GFP were finally recognized in 2008 -
techniques, and successfully studied numerous Shimomura, Chalfie and Tsien were awarded the
critical proteins in fruit fly development [5]. Nobel Prize in Chemistry [8].

In the following years, biochemists Roger And who would have thought that jellyfishes’
Tsien and other scientists made alterations, by exquisite glow would light the way in biological
introducing mutations to the original GFP. This research?
results in many new versions of GFP, including

Emerald from the Sea –

Green Fluorescent Protein

References 參考資料：
[1] Ferry, G. (2018, November 13). Osamu Shimomura (1928–2018). Retrieved from https://www.nature.com/articles/d41586-018-07401-1
[2] Shimomura, O. (2008). DISCOVERY OF GREEN FLUORESCENT PROTEIN, GFP. Nobel Lecture presented in Marine Biological Laboratory,
Woods Hole, MA 02543, USA. Retrieved from https://www.nobelprize.org/uploads/2018/06/shimomura_lecture.pdf
[3] Morin, J. G., & Hastings, J. W. (1971). Energy transfer in a bioluminescent system. Journal of Cellular Physiology, 77(3), 313-318.
doi:10.1002/jcp.1040770305
[4] Zimmer, M. (n.d.). Green Fluorescent Proteins - Douglas Prasher. Retrieved from https://www.conncoll.edu/ccacad/zimmer/GFP-ww/
prasher.html
[5] Chalfie M., Tu Y., Euskirchen G., Ward W. W., & Prasher D. C. (1994). Green fluorescent protein as a marker for gene expression. Science,
263(5148), 802-805.
[6] Zimmer, M. (n.d.). GREEN FLUORESCENT PROTEIN: A MOLECULAR MICROSCOPE. Retrieved from http://photobiology.info/Zimmer.html
[7] Campbell, R., Tour, O., Palmer, A., Steinbach, P., Baird, G., Zacharias, D., & Tsien, R. (2002). A monomeric red fluorescent protein.
Proceedings of the National Academy of Sciences of the United States of America, 99(12), 7877-7882.
[8] Nobel Media AB (2018). The Nobel Prize in Chemistry, 2008. Press Release. Retrieved from
https://www.nobelprize.org/prizes/chemistry/2008/press-release/