Identification of Cys255 in HIF-1α as a novel site for development of covalent inhibitors of HIF-1α/ARNT PasB domain protein–protein interaction

摘要: The heterodimer HIF-1α (hypoxia inducible factor)/HIF-β (also known as ARNT-aryl hydrocarbon nuclear translocator) is a key mediator of cellular response to hypoxia. interaction between these monomer units can be modified by the action small molecules in binding interface their C-terminal heterodimerization (PasB) domains. Taking advantage presence several cysteine residues located allosteric cavity PasB domain, we applied cysteine-based reactomics “hotspot identification” strategy locate regions domain critical for its with ARNT. COMPOUND 5 was identified using mass spectrometry-based primary screening and shown react specifically Cys255 domain. Biophysical characterization domains ARNT revealed that covalent reduced affinity approximately 10-fold. Detailed NMR structural analysis HIF-1α-PasB-COMPOUND conjugate showed significant local conformation changes associated involved HIF-1α/ARNT crystal structure heterodimer. Our could other targets identify pockets surrounding reactive cysteines suitable development molecule modulators protein function.