Plant hormone regulation on scopoletin metabolism from culture medium intotobacco cells

Tobacco (Nicotiana tabacum L. Bright Yellow) T-13 cell line has an ability for production of scopoletin. In this cell culture, scopoletin is taken up from culture medium and accumulated in vacuoles after conversion to scopoli n when cells are treated with 2,3-dichlorophenoxyacetic acid (2,4-D) (Taguc hi et al. (2000)). To clarify the effect of 2,4-D on tobacco cells, its int eraction with several other plant hormones was investigated. Other auxins a lso stimulated the uptake in the same manner as 2,4-D did, although higher concentrations were required than that of 2,4-D. When p-chlorophenoxyisobut yric acid (PCIB), an antiauxin, was added to the cell culture before 2,4-D, it inhibited 2,4-D-stimulated scopoletin uptake. This result suggests that the stimulation of scopoletin uptake was one of the auxin effects on tobac co cells. Among other classes of plant hormones that were tested: only sali cylic acid stimulated the uptake. When these hormones were added to the cel l cultures before 2.4-D, methyl jasmonate and kinetin reduced scopoletin up take. These results suggest that this scopoletin uptake by tobacco cells is regulated by the interaction between different plant hormones. (C) 2001 El sevier Science Ireland Ltd. All rights reserved.