Response to cold stress. Control plants are kept at room temperature. Plants are placed in X-gluc solution. Plants are gently removed from soil and put in a microfuge tube containing a small volume of X-gluc solution. Plants are left in the X-gluc solution for 2 hours at 37oC or overnight at room temperature.
Ethanol extracts the chlorophyll.
Store aliquots of the solution in the dark in a refrigerator or freezer. For example, students might devise experiments to determine the shortest exposure to cold that will induce the cor15a gene. They might test the effect of different temperatures, including high temperatures on the expression of the reporter gene. They might examine the effects of drought or other environmental changes or the effects of abscisic acid. Other GUS reporter gene fusions used in plants are in the scientific literature.