Stress response of OsETHE1 is altered in response to light and dark conditions.

ETHYLMALONIC ENCEPHALOPATHY PROTEIN1 (ETHE1), encoding sulfur dioxygenase activity is believed to be an important candidate in sulfur metabolism, where it is involved in amino acid catabolism during carbohydrate starvation and embryo development as seen in Arabidopsis thaliana. OsETHE1, an ETHE1-encoding gene from rice, is in fact induced in response to abiotic stresses, condition which affects nutritional status of the plant, reflecting the need for nutrient remobilization. Sulfur reduction and assimilation are believed to be light-dependent processes and so the genes involved in sulfur oxidation must also be investigated for light-dependent regulatory effects. To this end, we show that the stress response of OsETHE1 is dependent on light and that darkness largely suppresses the stress response of this gene. However, the observed regulatory effect is intricate, varying according to the stress imposed; thereby suggesting the involvement of various aspects of signaling in this process.