Abstract
Fatty acid alpha-oxygenase, which is one of the oxylipin metabolism enzymes, produces fatty acid alpha-hydroperoxide by insertion of one oxygen molecule to the alpha-position of free fatty acids. It is known that the fatty acid alpha-oxygenases in dicotyledonous plants such as Arabidopsis and tobacco are induced by pathogen infection and oxidative stress. However, the physiological function of fatty acid alpha-oxygenase is still unclear. In this study, in order to elucidate the physiological function of fatty acid alpha-oxygenase, the expression profile of the enzyme was investigated with rice. Although the fatty acid alpha-oxygenases in dicotyledonous plants were mainly induced via the salicylic acid pathway, that in rice was markedly increased only by the jasmonic acid pathway but not by the salicylic acid pathway. In rice seedlings of 9 days after germination, fatty acid alpha-oxygenase was induced by oxidative stress caused by methyl viologen and by heavy metal-ion stress.
