Figure 3: Structural analysis of GIF:IL-2 and GIF:GM-CSF complexes by negative-stain EM.
From: Structural basis of GM-CSF and IL-2 sequestration by the viral decoy receptor GIF
(a) Gallery of representative ab initio class averages of the GIF:IL-2 complex and projections of the final 3D reconstruction under similar orientations. (b) Ab initio class averages of the GIF:GM-CSF complex and projections of the GIF:GM-CSF crystal structure under similar orientations. (c) Front and side views of a 3D reconstructed EM map for the GIF:IL-2 complex. The 3D volume displays a characteristic horseshoe shape. (d) Fit of the crystal structure of dimeric GIF and a homology model of ovine IL-2 in the corresponding EM map. The resulting model displays a horseshoe shaped complex formed by a GIF dimer bound by two copies of IL-2 (GIF dimer: green/dark green, IL-2: orange/dark orange) and displays a two-fold symmetry axis centered at the GIF dimer interface, indicated as a black oval.
