Using semi-qRT-PCR, DWF4 hnRNA and mRNA levels were measured to evaluate the effects of Brz and BL on DWF4 transcription. To detect both RNA species, we designed two types of primer (arrow) sets, shown in a schematic diagram of gene expression. The lengths (bp) of the PCR products derived from both RNAs are shown in parentheses (A). Fourteen-day-old wild-type Arabidopsis plants were cultured in liquid MS medium containing 5 µM Brz for the indicated number of days to evaluate the effect of Brz, whereas the seedlings were incubated in the same medium containing 5 µM Brz for 2 days and then cultured in the presence of 0.1 µM BL for the indicated number of hours to evaluate the effect of BL (B). The fluorescence intensity of ethidium bromide of each PCR product band was scanned with a fluoro-image analyzer (FLA 2000; Fujifilm, Tokyo, Japan) after electrophoresis. The relative fluorescence values are shown in graphs comparing the initial period after normalization with that of ACT2, which was used as an internal control. Each experiment was conducted in biologically triplicate, and the means ± SE were calculated.