5LXF

Crystal structure of the human Macrophage Colony Stimulating Factor M- CSF_C31S variant

Summary for 5LXF

• Entry DOI: 10.2210/pdb5lxf/pdb
• Descriptor: Macrophage colony-stimulating factor 1 (2 entities in total)
• Functional Keywords: drug design, rational protein engineering, receptor tyrosine kinase, osteoporosis, signaling protein
• Biological source: Homo sapiens (Human)
• Total number of polymer chains: 2
• Total formula weight: 42709.47

Authors

Shahar, A.,Papo, N.,Zarivach, R.,Kosloff, M.,Bakhman, A.,Rosenfeld, L.,Zur, Y.,Levaot, N. (deposition date: 2016-09-21, release date: 2017-07-12, Last modification date: 2024-10-16)

Primary citation

Zur, Y.,Rosenfeld, L.,Bakhman, A.,Ilic, S.,Hayun, H.,Shahar, A.,Akabayov, B.,Kosloff, M.,Levaot, N.,Papo, N.
Engineering a monomeric variant of macrophage colony-stimulating factor (M-CSF) that antagonizes the c-FMS receptor.
Biochem. J., 474:2601-2617, 2017

PubMed Abstract: Enhanced activation of the signaling pathways that mediate the differentiation of mononuclear monocytes into osteoclasts is an underlying cause of several bone diseases and bone metastasis. In particular, dysregulation and overexpression of macrophage colony-stimulating factor (M-CSF) and its c-FMS tyrosine kinase receptor, proteins that are essential for osteoclast differentiation, are known to promote bone metastasis and osteoporosis, making both the ligand and its receptor attractive targets for therapeutic intervention. With this aim in mind, our starting point was the previously held concept that the potential of the M-CSF mutant as a therapeutic is derived from its inability to dimerize and hence to act as an agonist. The current study showed, however, that dimerization is not abolished in M-CSF and that the protein retains agonistic activity toward osteoclasts. To design an M-CSF mutant with diminished dimerization capabilities, we solved the crystal structure of the M-CSF dimer complex and used structure-based energy calculations to identify the residues responsible for its dimeric form. We then used that analysis to develop M-CSF, a ligand-based, high-affinity antagonist for c-FMS that retained its binding ability but prevented the ligand dimerization that leads to receptor dimerization and activation. The monomeric properties of M-CSF were validated using dynamic light scattering and small-angle X-ray scattering analyses. It was shown that this mutant is a functional inhibitor of M-CSF-dependent c-FMS activation and osteoclast differentiation Our study, therefore, provided insights into the sequence-structure-function relationships of the M-CSF/c-FMS interaction and of ligand/receptor tyrosine kinase interactions in general.

PubMed: 28655719
DOI: 10.1042/BCJ20170276

Experimental method

X-RAY DIFFRACTION (2 Å)