Figure 5.

ABI5 Expression Is Downregulated in rgl2 Seeds under Low-GA Conditions.

(A) RNA and protein gel blot analysis of a time course of ABI5 mRNA and protein levels upon wild-type (Col) and rgl2-13 seed imbibition in the presence of 5 μM PAC, an inhibitor of GA synthesis. Two micrograms of total RNA was used per lane. DS, dry seeds; rRNA, rRNA loading control. Ten micrograms of total protein was used per lane. Protein extracts were stained with Ponceau S as a loading control prior to detection with antibodies against ABI5. Compare with normal conditions in Figure 1.

(B) RNA and protein gel blot analysis of a time course of ABI5 mRNA and protein levels upon wild-type (Col) and rgl2-13 seed imbibition in the presence of 5 μM ABA. Two micrograms of total RNA was used per lane. Ten micrograms of total protein was used per lane. Protein extracts were stained with Ponceau S as a loading control prior to detection with antibodies against ABI5.

(C) Protein gel blot analysis of ABI5 protein levels upon imbibition of ga1-3 and ga1-3/rgl2-13 seeds under normal conditions. Each lane contained protein extracted from 100 seeds, and Ponceau S staining is shown as a loading control. Germination percentage at each time point is indicated.