Entwicklung konformationsspezifischer Furin-Inhibitoren



“The proprotein convertase (PC) furin is a highly specific serine protease involved in the proteolytic maturation of many proteins in the secretory pathway. Similarly, several pathologies such as rheumatoid arthritis and cancer are connected to increased furin activity. Host cell furin is also hijacked by many bacteria and viruses, requiring proteolytic maturation of their toxins and glycoproteins, respectively. Thus, furin inhibitors are promising therapeutics against many diseases and can serve as versatile tools to investigate the physiological functions of this protease and its substrates, e.g., as activity-based probes. Substrate-like furin inhibitors have been developed based on its sequence specificity. These compounds rely on interactions with the highly conserved core segment of the substrate binding site comprising the so-called S1-S4 pockets. However, this strategy proved to be challenging in obtaining selective furin inhibitor. The cross reactivity with several PC family members limits the application of substrate-like ligands as activity probes and inhibitors in biochemical and cell biological studies. The overall aim of the proposed project is the structure-guided discovery and development of selective furin inhibitors with improved biochemical and pharmacological properties.
To reach this goal we will capitalize specifically the conformation of ligand free furin, which we discovered and referred to as the “OFF”-state. The accessible interaction surface in the “OFF”-state is largely different to the canonic interface bound by substrate like ligands (Fig. 4A). These structural features can be specifically targeted by crystallography based fragment screening using crystals of unliganded furin and high throughput protein X-ray crystallography. This approach facilitates the de-novo identification of novel ligands and provides detailed structural information of the interaction site. Due to the differences in conformation and charge distribution, specific ligand interaction patterns are expected for OFF-state furin, including binding sites at the less conserved rim of the active site cleft. To identify furin-specific ligands we plan comparative binding analyses with the PC family members PACE4 and PC7 using biochemical and biophysical methods. The most promising ligands will serve as starting point for the development of novel lead compounds by chemical optimization. Complementarily, we plan to improve an existing “OFF”-state specific small molecule furin inhibitor.”
KurztitelEntwicklung konformationsspezifischer Furin-Inhibitoren
Tatsächlicher Beginn/ -es Ende2/03/201/03/22