Residues Clustered in the Light-Sensing Knot of Phytochrome B are Necessary for Conformer-Specific Binding to Signaling Partner PIF3
A) In vitro co-immunoprecipitation assays of wild-type and mutant Pr and Pfr phyB, performed as in Figure 2. B) Quantification of phyB binding to GAD-PIF3. Black bars represent the wild type interaction and orange bars represent the interaction of the mutants with GAD-PIF3. Inset shows inputs. Quantification is relative to amount of input and amount of GAD-PIF3. Interaction of wild-type Pr phyB with GAD-PIF3 is set equal to one. C) Hypocotyl phenotypes of 4d-old seedlings grown continuously in the dark (D), red (R), or far red (FR) light. Shown are the parental phyB null mutant (phyB) and transgenic lines expressing either a full-length wild-type phyB-GFP-fusion sequence (PBG) or phyB-mutant variants thereof (R110Q, G111D, R352K) in the phyB mutant background.