Figure 5.

Expression pattern of light-regulated marker genes during seedling deetiolation. A, Expression of light-induced marker genes after a red light pulse. Ler wild-type and eid3 mutant seedlings were grown in darkness for 4 d after induction of germination. Expression of light-regulated genes was induced by a saturating 2-min red light pulse. The gel shows representative results of three independent experiments. HY5, PKS1, CHS, and PSAE transcript levels were monitored at the indicated time points after the red light pulse using RT-PCR. ACT transcript levels served as a constitutive control. Gels were stained with SYBR-safe DNA gel stain. Images are shown inverted. B, Quantification of transcript levels of light-induced HY5 and PKS1 marker genes in eid3, pft1-2, and the corresponding Ler and Col wild types. Seedlings were treated as described for A. Transcript levels were determined by quantitative real-time PCR analyses. Results of experiments were normalized according to the constitutively expressed ACT gene. Data represent means of three independent biological replicates ± se. Rp, 2-min red light pulse; cD, dark control. C, Light-independent expression of light-induced marker genes in the eid3 mutant and the Ler wild type. Germination was induced by either 2 h of continuous red light without GA (−GA) or without light treatment and application of 10 µm GA (+GA). Seedlings were grown in darkness for 4 d after germination induction. Expression of light-induced genes was initiated by a saturating 2-min red light pulse, and samples were harvested at 1 and 4 h or before light treatment (0 h). Transcript levels were monitored as described for A. The gel shows the representative result of two independent experiments.