Figure 7.

ASR5 Binds to the STAR1 Promoter In Vitro.

(A) ChIP qPCR results showing enrichment of the STAR1 promoter region using the α-ASR5 antibody.

(B) Scheme showing the amplification sites for the STAR1 promoter.

(C) SAPA pull-down system showing that ASR5–GST binds to an F1 biotinylated DNA fragment (F1*). Fragments F1, F2, F3, and Di-Dc were used as competitors. GST alone was used as a negative control.

(D) Transient gene expression assays demonstrating the regulation of STAR1 by ASR5 using GUS/luciferase assays.

(E) A proposed model for the ASR5–STAR1 promoter interaction. ART1 does not respond to Al in rice but maintains a housekeeping expression level of STAR1 under control conditions. In response to Al, ASR5 binds to the STAR1 promoter to enhance its expression. Adapted from Delhaize et al. (2012).