Figure 5.

Fluence response characteristics of transgenic constructs containing the −281 to +2, −281 to +64, and −150 to +64 versions of the pea Lhcb1*4 promoter. A, Six-day-old dark-grown transgenic Arabidopsis containing truncated pea Lhcb1*4 promoter constructs fused to GUS were irradiated with a single pulse of BL with a total fluence of 10⁴ μmol m⁻² or were given no light (D). RNA was prepared 2 h after the light treatment and analyzed by slot blotting. The resulting blots were probed for GUS and Lhcb RNA, representing expression of the transgene and the endogenous Arabidopsis Lhcb, respectively. The pea Lhcb1*4 promoters (as indicated on the figure) extend from either −281 or −150 on the upstream end to either +65 (+5′-UTR, where +1 represents the site of transcriptional initiation, +1 to+64 represents the pea Lhcb1*4 5′-UTR and +65 is the A of the ATG start codon) or +2 (−5′-UTR) on the downstream end. B, Compilation of three independent experiments. All data points were plotted relative to dark levels (set to 1%) and 10⁴ μmol m⁻² BL levels (set to 100%) and represent the constructs −281 with a 5′-UTR (white bars), −281 without a 5′-UTR (light gray bars), −150 with a 5′-UTR (dark gray bars), and the endogenous Lhcb gene (black bars). All signals were normalized to rRNA. Error bars indicate se of the mean.