Figure 5.

Exploring functional redundancy among class B Hsfs for the regulation of HsfA2 expression. A, An alignment of the core sequence of BRD of Arabidopsis class B Hsfs. B, Relative LUC activities after cobombardment of Arabidopsis leaves with plasmids encoding class B Hsf effectors and the ProHsfA2:LUC reporter gene. After particle bombardment, the Arabidopsis leaves were incubated in the dark for 5 h at 23°C, 1 h at 37°C, and then 1 h at 23°C. The relative activity due to the pUC18 vector (gray bar; cont) was taken as 1. Error bars indicate sd (n = 9). Asterisks indicate P values below 0.05 between the control and others. C, Interaction of HsfB1 and HsfB2b in the promoter region of HsfA2 analyzed in the yeast one-hybrid system. The transformed yeast cells were grown on medium containing 60 mm 3-amino-1,2,4-triazole. pDEST_GAD424 empty vector was used as a negative control that contains the activation domain only [AD(cont)]. [See online article for color version of this figure.]