Figure 5.

Expression of the GA3 mRNA. The abundance of the GA3 transcript was determined by RNase protection. For each panel the amount of input RNA for each lane was shown to be equal by spectrophotometer and ethidium stained agarose gel analysis. The sizes of the protected fragments from the full-length mRNA (225 nt) and the product of aberrant splicing of intron 6 (186 nt) are shown. Sizes of protected fragments were determined by comparison to end-labeled single stranded DNA fragments from an MspI digest of pBR322. (A) Expression of the GA3 mRNA in Arabidopsis (L.er) seedlings at 5, 12, and 19 days old. RNA was prepared from the aerial parts of the plants. (B) Expression of the GA3 mRNA in tissues of flowering Arabidopsis (L.er) plants. RL; rosette leaf, CL; cauline leaf, Stem; elongating stems stem, Infl; inflorescence. (C) Effect of gibberellic acid (GA₃) and ga mutations on the expression of the GA3 mRNA. RNA was prepared from the inflorescence of flowering plants. Yeast control reaction contained 50 μg of yeast RNA hybridized to the GA3 probe and treated with RNase.