Abstract
Detailed mechanisms of the damage to plants caused by ozone have not been clarified yet. To dissect these mechanisms, we screened ozone sensitive mutants from Arabidopsis T-DNA tagging lines by visible injury.
Ethylene is one of the plant hormones, and trigger of cell death. Ethylene emission during an ozone exposure in one of these mutants was higher than that of wild type (Ws-2).
Since jasmonate is known to be involved in plant defence response, we examined methyl-jasmonate (MeJA) sensitivity of the mutant by the inhibition of root elongation. Sensitivity to MeJA of the mutant is lower than that of Ws-2. Therefore, this mutant was named oji1 (Ozone-sensitive, Jasmonate-Insensitive 1).
Treatment by MeJA at low concentration decreased ethylene emission and ion leakage during ozone exposure in Ws-2 but not inoji1.
These results suggest that the ozone sensitivity of oji1 might be caused by ethylene over-emission in consequence of jasmonate insensitivity.
