FIGURE 3.

Serotonin induces defense gene expression and cell death in rice suspension cell cultures. Total RNAs were prepared from rice suspension cells either mock-treated or treated with 400 μg/ml serotonin or tryptamine. The samples were subjected to real time PCR to analyze expression of PBZ1 (A), PAL1 (B), Cht1 (C), and Cht3 (D). Ubiquitin (Ubq) was used as an internal control. Error bars indicate S.D. E, rice suspension cultured cells were treated with 400 μg/ml serotonin or tryptamine. The levels of cell death were measured using Evans Blue staining.