Figure 2.

Expression of selected genes of chlorophyll biosynthesis and HSP70B in mutants lacking cytb₆/f complex components. A, RNA-blot analysis, details of which are given in “Materials and Methods.” Prior to light exposure, cultures were incubated in the dark for 20 h (D). Then, cultures were shifted to light (fluence rate 40 μE m⁻²·s⁻¹) for 1 h (L1) and 2 h (L2). At these time points samples were taken for RNA extraction. For RNA-blot analyses, 10 μg of total RNA were hybridized with probes specific for the genes indicated. The constitutively expressed CBLP gene, encoding a Gβ-like protein (von Kampen et al., 1994), served as a loading control. B, Quantitative evaluation of RNA-blot data from at least three experiments. The relative induction of each gene with sem was normalized using the signal for the CBLP gene. The induction ratios given were determined by dividing the values of the L2 samples by those of the D samples.