Fig. 2: SPX1-PHR2 CC interface is compatible with PHR2 dimer interface.
From: Mechanism of phosphate sensing and signaling revealed by rice SPX1-PHR2 complex structure
a The crystal structure of InsP6-SPX1-PHR2 complex. SPX1 was colored in wheat, and the MYB and CC domains of PHR2 were colored in light blue and pale cyan respectively. InsP6 was represented as a stick model in red. InsP6-SPX1-PHR2 complex was shown in two opposite views. The secondary structure elements and InsP6 molecule were labeled. b Close-up view of SPX1-PHR2 CC domain interface. Critical interface residues were shown as sticks and labeled. The yellow dashed lines represent hydrogen bonds involved in the interaction of SPX1 and PHR2. c Mutations compromised the SPX11–198-PHR2248–380 complex formation. (Upper) Gel filtration profiles of SPX11–198 and PHR2248–380 were color-coded to show different SPX11–198 mutants and PHR2248–380 mutants. (Lower) Coomassie-blue stained SDS-PAGE gels of peak fractions. Experiments were independently repeated three times with similar results. Uncropped gel images are available as source data. d SPX1-PHR2 CC interface does not interfere with PHR2 dimerization. (Left) Superimposition InsP6-SPX1-PHR2-ternary complex structure onto AtPHR1 CC (PDB:6TO5) dimer structure. (Right) Surface representation of rice PHR2 CC dimer model. SPX1-binding interface was colored in wheat and PHR2 dimer interface was colored in teal.
