An allosteric switch for pro-HGF/Met signaling using zymogen activator peptides

Abstract

Stimulation of hepatocyte growth factor (HGF) signaling through the Met receptor is an attractive approach for promoting tissue repair and preventing fibrosis. Using structure-guided peptide phage display combined with an activity-based sorting strategy, we engineered allosteric activators of zymogen-like pro-HGF to bypass proteolytic activation and reversibly stimulate pro-HGF signaling through Met. Biochemical, structural and biological data showed that zymogen activator peptides (ZAPtides) potently and selectively bind the activation pocket within the serine protease-like β-chain of pro-HGF and display titratable activation of pro-HGF-dependent Met signaling, leading to cell survival and migration. To further demonstrate the versatility of our ZAPtide platform, we identified allosteric activators for pro-macrophage stimulating protein and a zymogen serine protease, Protein C, which also provides evidence for target selectivity. These studies reveal that ZAPtides use molecular mimicry of the trypsin-like N-terminal insertion mechanism and establish a new paradigm for selective pharmacological activation of plasminogen-related growth factors and zymogen serine proteases.

Probing conformational and functional states of human hepatocyte growth factor by a panel of monoclonal antibodies

“…Antibodies and their fragments are often used as “crystallization chaperone”, where the likelihood of obtaining well-ordered crystals of flexible proteins are increased by the formation of complex with a binder 22 . Currently, the structural information of HGF is available for only a limited set of domains including NK1, NK2 23 , and SP 10 11 24 , and no structures are available for K3 and K4 domains. More importantly, there is no high resolution structures available for the full-length HGF either before or after the proteolytic activation.…”

The cytokines of pulmonary fibrosis: Much learned, much more to learn

“…The relevance of HGF to pulmonary fibrosis has been emphasized by the findings of impaired activation of pro-HGF in patients with IPF [214] and in the bleomycin model in mice [215]. There have been substantial developments in exploring HGF and its engineered derivatives as promising therapeutic agents for fibrosis [212,216,217].…”

Semi-synthesis of a HGF/SF kringle one (K1) domain scaffold generates a potent in vivo MET receptor agonist

“…20,23 As a consequence, the systemic activity of HGF/SF in vivo has been observed only at very high doses incompatible with a clinical development. 24 Therefore, the development of novel potent MET agonists 20,25 or HGF/SF activators 26 acting systemically is of utmost medical importance.…”