Figure 5.
CRY1-dependent hypocotyl growth responses to blue light were enhanced by A9. Hypocotyl growth inhibition of 35S:A9 seedlings after illumination with blue light. (A) Hypocotyl length was measured in seedlings grown under darkness for 3 days and then illuminated under continuous monochromatic blue light (Bc) at a fluence rate of 20 μmol m−2. (B) The measured hypocotyl lengths from panel A are represented as the percentage of length measured after illumination with respect to that in dark-grown seedlings. This eliminated the differences between NT and 35S:A9 seedlings observed without illumination and allowed us to assay only the effect on the blue-light response. Note that in tobacco seeds, after 3 days of imbibition under darkness, growth was only detectable as the root point started to protrude the seed coat. Three pairs of 35S:A9/NT sibling lines were analyzed in at least two independent experiments. Numbers in brackets represent the number of measurements. Asterisks indicate the statistically significant differences (see Table S7). Error bars denote the SEM.