Teaching Plants to Speak the Color OrangeNeal StewartCollege of Agricultural Sciences and Natural Resources - Department of Plant Sciences
Phytosensors are engineered plants to report when specific contaminants and disease-causing agents are present in a plant's environment. Gene switches—called promoters—are being discovered which naturally sense, for example, when a harmful bacterium or virus attacks the plant. They naturally switch on a cascade of defenses. Our research group is designing stronger synthetic promoters, which are then used to control the expression of fluorescent protein genes. The brightest discovered fluorescent protein happens to be orange. However, it is still not bright enough to usually be visible under the control of even our stronger designer promoters. Recently, the group has made modifications to make a “Big Orange” fluorescent protein that is accumulated much higher in the plant, which yields three times higher fluorescence than its predecessor. Plants can be engineered temporarily for orange fluorescence, perhaps just in the leaves, to comprise a brief reporter system.