Fig. 3.

Phosphorylation alleviates ARF2 DNA binding and repressor activity. (A) DNA:protein pull-down experiments with biotinylated DNA fragments from SAUR-15 promoter with ARF2 translated in vitro. ARF2 protein was incubated with BIN2 or kinase-dead [K69R] BIN2 before pull-down experiments with DNA-bound streptavidin beads. Two representative examples from seven similar experiments are shown. BES1 does not interfere with ARF2 binding to DNA. Purified recombinant MBP-BES1 was added where indicated. (B) Yeast repression assay. Repression of the transcription of a LexAop-CYC1::LacZ reporter by a ARF2-LexA fusion in the presence or absence of BIN2 was assessed by β-galactosidase activity. Results are presented as mean of two separate assays of three independent transformants. Error bars indicate standard error.