Abstract
To closely analyze a role of reactive oxygen intermediates (ROI) in the cell death of F1 hybrid of Nictotiana gossei x N. tabacum, a cultured cell line (GTH4) from the F1 hybrid seedlings was established. GTH4 showed lethal symptoms at 26C but not at 37C, similar to the original hybrid plants. Larger amounts of O2- and H2O2 were detected in the cells at 26C than 37C. Pharmacological experiments using inhibitors and scavengers of ROI to the cells suggest that H2O2 had more direct effects on the process of cell death. Treatment of cells with H2O2 generating system (G/GO) induced cell death, while that with O2- generating system (X/XO) suppressed cell death. Simultaneous treatments with G/GO and X/XO also reduced the rate of cell death. These results indicate that H2O2 rather than O2- functions as a mediator in cell death of the hybrid.
