부산대학교 도서관

We have shown that plant cells act a defense reaction against chemical stress, such as geraniol and bornyl acetate. When the cultured shoot primordia of Marchantia chamomilla and cultured cells of Glycine max were treated with 5mM geraniol, the levels of glutathione S-transferase (GST) mRNA and the GST activity reach peaks at 4 and 8h, respectively. The mRNA levels of McEREBP1 and McWRKY1 transcription factors were severely elevated to maximum at 1h, after treatment of the cultures with geraniol. These increases were specific to geraniol, not geraniol isomers, nerol and linalool. The McEREBP1 may act to a transcription factor on the GST promoter. The p20, a novel-type of trypsin inhibitor mRNA, levels were decrease by the treatment of the cells with geraniol. These results suggest that induction of GST activity and loss of protease inhibitor may participate in defence reaction by monoterpenoid treatment. We reported that when the cultured cells of Marchantia polymorpha were treated with bornyl acetate as a chemical stress agent, the cells secreted lunularin, hydrogen peroxide, peroxidase and phosphatase. A peroxidase was purified from cultured medium and a full-length cDNA clone was isolated. The purified peroxidase catalyzed the oxidative polymerization of lunurarin with hydrogen peroxide. The peroxidase mRNA level elevated to maxima at 1h after treatment with bornyl acetate. An ATPase-like phosphatase was purified from cultured medium induced to chemical stress. The phosphatase differed from normal type phosphatase secreted without chemical stress. These indicated that the secreted peroxidase and ATPase-like phosphatase reinforce cell wall to chemical stress, because the peroxidase promote oxidative coupling of lunularin and hydrogen peroxide.