- Mohan K, Ueda G, Kim AR, Jude KM, Fallas JA, Guo Y, Hafer M, Miao Y, Saxton RA, Piehler J, Sankaran VG, Baker D, Garcia KC
- Topological control of cytokine receptor signaling induces differential effects in hematopoiesis.
- Science. 2019 May 24;364(6442). pii: 364/6442/eaav7532. doi:, 10.1126/science.aav7532. Epub 2019 May 23.
- Although tunable signaling by G protein-coupled receptors can be exploited through medicinal chemistry, a comparable pharmacological approach has been lacking for the modulation of signaling through dimeric receptors, such as those for cytokines. We present a strategy to modulate cytokine receptor signaling output by use of a series of designed C2-symmetric cytokine mimetics, based on the designed ankyrin repeat protein (DARPin) scaffold, that can systematically control erythropoietin receptor (EpoR) dimerization orientation and distance between monomers. We sampled a range of EpoR geometries by varying intermonomer angle and distance, corroborated by several ligand-EpoR complex crystal structures. Across the range, we observed full, partial, and biased agonism as well as stage-selective effects on hematopoiesis. This surrogate ligand strategy opens access to pharmacological modulation of therapeutically important cytokine and growth factor receptor systems.