Figure 6.

BPBF negative regulation of the transcription of AL21 thiol protease promoter. Intact aleurone layers were prepared from half-grains and were transfected by particle bombardment with the indicated combinations of reporter and effector plasmids at a 1:1 molar ratio. A, Effect of BPBF on the AL21 promoter activity of the reporter construct pCBG13. + indicates the presence and − indicates the absence of the effector constructs shown at the left (BPBF and/or GAMYB). When indicated, half-grains were incubated in the presence of 1 μm GA₃. B, Effect of BPBF on the GA-induced transcription of three different AL21 promoter constructs. Aleurone cells were bombarded with the reporter construct indicated, alone (white bars) or in combination (1:1 molar ratio) with the BPBF effector (dashed bars), and were then incubated with 1 μm GA₃. The p35S construct, where the GUS reporter gene was under the control of the CaMV35S promoter, was used as a control. Relative GUS activity is shown, considering expression levels of the pCBG13 construct in the presence of GA3 as 100%. Column height represents the mean value of 12 replicates from three independent experiments. Bars indicate ses.