Fig. 3
From: Structural basis for potency differences between GDF8 and GDF11
The structure of the GDF11:FS288 complex. a Comparison of the GDF11:FS288 (top) and GDF8:FS288 (bottom; Protein Data Bank (PDB) 3HH2; [54]) structures. The inset shows the differences between the interaction of the FSND helix and the ligand type I receptor epitope. Recombinant human GDF11 was obtained from Acceleron Pharma for resolution of this crystal structure. b Isoelectric surface representation of the GDF11:FS288 (left) and GDF8:FS288 (right) structures. Surfaces are colored blue (positive) and red (negative) on a scale of –5 to 5 kbT/ec using the APBS plugin [97] for PyMol. c Heparin affinity analysis of FS288 alone, GDF11:FS288, and GDF8:FS288 complexes. GDF11:FS288 complex has higher affinity for heparin than FS288 alone indicated by elution at a higher ionic strength. Purified proteins and complexes (100 μg) were applied to a heparin column and eluted with a linear sodium chloride (NaCl) gradient. The approximate NaCl concentration for protein elution is shown at the peak maxima. Ligand source: gift from Acceleron Pharma