[31]

PROFILING THE STRESS RESPONSE OF ARABIDOPSIS USING GREEN FLUORESCENT PROTEIN: A PRELUDE TO A FLIGHT EXPERIMENT.  T. Do¹, A-L. Paul² and R. J. Ferl². ¹Spaceflight and Life Sciences Training Program (SLSTP), Kennedy Space Center,  ²University of Florida, Gainesville, FL

   Stress responses in the plant Arabidopsis were initiated by the application of four different stress types: flooding, increased ethylene, increased ethylene with KMnO₄ to absorb the hormone, and a decreased temperature. An engineered reporter gene comprised of the alcohol dehydrogenase (Adh) promoter driving the Green Fluorescent Protein (GFP) reporter was incorporated into Arabidopsis to follow these stress responses in real time. The results were read visually with imagery from fluorescent microscopy and the gene expression was evaluated quantitatively with Real-Time Polymerase Chain Reaction (RT-PCR) “Taqman™” (ABI) chemistry.  Images were read at 24 hr, 72 hr, and 120 hr intervals, then compared to positive control plants transformed with a reporter gene that is constitutively expressed (CaMV35s/GFP).  The fluorescent microscopy results showed the GFP expression primarily in the roots for the flooding and ethylene treatments while expression was shown principally in the leaves for the reduced temperature stress.  Another important result showed no significant difference between the standard ethylene treatment and the sample subjected to KMnO₄ for ethylene absorption.

[