Fig. 4: HY5 enhances BIN2-mediated phosphorylation of BZR1 through its C-terminal domain.
From: Modulation of BIN2 kinase activity by HY5 controls hypocotyl elongation in the light
a In vitro kinase assay showing HY5 enhanced kinase activity of BIN2. MBP-BZR1 was used as substrate for BIN2. 1, 2, 4, 8 indicate the mole ratios of HY5-His versus His-BIN2. pBZR1, phosphorylated BZR1; pBIN2, auto-phosphorylated BIN2. 32P, autoradiography of [γ-32P] ATP-labeled proteins. WB, western blot of proteins used in the kinase assay. b Cell-free kinase assay showing BIN2-mediated phosphorylation of BZR1 in the total lysates of Col and hy5. Seedlings grown in cWL were grown for another day in cWL, or transferred to the dark (L to D) for 1 day. Actin was used as a loading control. c Mapping the region of HY5 that was essential for the promotion of BIN2 activity in vitro. Asterisks indicate non-specific bands. d BZR1 protein levels in transgenic plants that overexpressed full-length and truncated HY5 in the hy5 background. Short exp., short exposure. Long exp., long exposure. HSP was used as a loading control. Numbers under lanes in b and c indicate relative band intensities that were quantified for each panel. Source data are provided as a source data file.
