Fig. 4.
Reverse transcriptase-polymerase chain reaction (RT-PCR) expression profiles for PYD1–3 in 17-d-old liquid-cultured Arabidopsis seedlings grown in 1/2 × Murashige and Skoog (MS) medium, with a fresh medium change at Day 9. Time = 0 h is 4 h after the beginning of the light period, when cultures received either no supplements (control) or NH3, dihydrouracil (DHU) or uracil (Ura) at 5 mm final concentration. Expression values for each transcript at 2, 6 or 21 h after supplement addition are relative to those in control plants, normalized on the basis of ACT2expression, and are indicated below each band.