Figure 3.

AREB1ΔQT Is a Constitutive Active Form of AREB1 in Planta.

(A) RNA gel blot analysis of AREB1 and RD29B expression in wild-type, vector control (vector), 35S-AREB1, and 35S-AREB1ΔQT plants. Two-week-old seedlings were either not treated (−) or treated (+) with ABA for 7 h. Each lane contained 10 μg of total RNA. Two lines of the 35S-AREB1 plants (3 and 6) and three lines of the 35S-AREB1ΔQT plants (5, 12, and 26) are shown. rRNAs on ethidium bromide–stained gel are shown as equal loading controls.

(B) Growth phenotype of 35S-AREB1ΔQT (line 5) and 35S-AREB1 (line 6) plants that were grown for 3 weeks on GM agar plates containing 1% sucrose.

(C) Maximum rosette radius (i.e., length of the longest rosette leaf) of each plant on a GM agar plate containing 3% sucrose was measured 3 weeks after stratification. Three independent lines of wild-type plants and nine independent lines of 35S-AREB1ΔQT plants were used. Bars indicate standard deviation; n = 7.

(D) Expression profile of downstream genes identified by microarray analysis (Table 1) in 35S-AREB1ΔQT plants (line 5). Two-week-old seedlings were either not treated (−) or treated (+) with ABA for 7 h. Each lane contained 7 μg of total RNA. Three to eight independent lines were used, and results from one representative experiment are shown. rRNAs on ethidium bromide–stained gel are shown as equal loading controls.