Figure 8.

Cryptochromes mediate transient blue light suppression of GA₄. The GA₄ content of 6-d-old etiolated wild-type (WT) and cry1cry2 mutant seedlings exposed to blue light (60 μmol m⁻² s⁻¹) for 4 or 24 h are shown in A. The GA₄ content of 5-d-old wild-type (WT) and cry1cry2 mutant seedlings grown in continuous dark or continuous blue light are shown in B. Asterisk indicates a significant difference (P < 0.05, two-way ANOVA). D, Dark; B4 and B24, etiolated seedlings exposed to blue light for 4 and 24 h, respectively; Bc, seedlings grown in continuous blue light. GA₄ in whole seedling samples except roots was separated by HPLC and analyzed by gas chromatography-MS.