Abstract
To understand how boron (B) deficiency damages plant cells, responses to B-deprivation were studied in tobacco BY-2 cells.
The genes of which expression are up-regulated in low B-tolerant cells (acclimated to a medium containing 0.05 mg B liter-1) were screened with cDNA differential subtraction method. The low B-specific genes include putative antioxidant enzymes such as catalase, glutathione S-transferase, and a glucosyltransferase of phenylpropanoid biosynthesis pathway. This suggests that the acclimated cells have enhanced activity to tolerate oxidative conditions, and that B deficiency may cause oxidative damages to the cells. The generation of reactive oxygen species under B deficiency is now under examination.
Some of the low B-specific genes were induced within 30 minutes after the removal of B from the medium. The result indicates that the absence of B from the surrounding medium immediately affects the cellular functions.
