Host: The Japanese Society of Plant Physiologists
Pages 0030
To better understand plant Se toxicity and resistance mechanisms, we compared the physiological and molecular responses of two Arabidopsis accessions, Col-0 and Ws-2, to selenite treatment. Measurement of root length demonstrated a clear difference between selenite-resistant Col-0 and selenite-sensitive Ws-2. Macroarray analysis showed more pronounced selenite-induced increases in mRNA levels of ethylene or jasmonic acid (JA) biosynthesis and -inducible genes in Col-0 than in Ws-2. Indeed, Col-0 exhibited higher levels of ethylene and JA. The selenite-sensitive phenotype of Ws-2 was attenuated by treatment with ethylene precursor or MeJA. Conversely, the selenite resistance of Col-0 was reduced in mutants impaired in ethylene- or JA-biosynthesis or signaling. Furthermore, the generation of reactive oxygen species (ROS) by selenite was higher in Col-0 than in Ws-2. Together these results indicate that JA and ethylene play important roles in Se resistance in Arabidopsis.
