title: Protein painting reveals solvent-excluded drug targets hidden within native protein-protein interfaces.
abstract: Identifying the contact regions between a protein and its binding partners is essential for creating therapies that block the interaction. Unfortunately, such contact regions are extremely difficult to characterize because they are hidden inside the binding interface. Here we introduce protein painting as a new tool that employs small molecules as molecular paints to tightly coat the surface of protein-protein complexes. The molecular paints, which block trypsin cleavage sites, are excluded from the binding interface. Following mass spectrometry, only peptides hidden in the interface emerge as positive hits, revealing the functional contact regions that are drug targets. We use protein painting to discover contact regions between the three-way interaction of IL1β ligand, the receptor IL1RI and the accessory protein IL1RAcP. We then use this information to create peptides and monoclonal antibodies that block the interaction and abolish IL1β cell signalling. The technology is broadly applicable to discover protein interaction drug targets.
authors.affiliation: Center for Applied Proteomics and Molecular Medicine, George Mason University, 10900 University Boulevard, Manassas, Virginia 20110, USA.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Luchini
authors.affiliation: Center for Applied Proteomics and Molecular Medicine, George Mason University, 10900 University Boulevard, Manassas, Virginia 20110, USA.
authors.forename: Virginia
authors.initials: V
authors.lastname: Espina
authors.affiliation: Center for Applied Proteomics and Molecular Medicine, George Mason University, 10900 University Boulevard, Manassas, Virginia 20110, USA.
authors.forename: Lance A
authors.initials: LA
authors.lastname: Liotta
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D004396:Coloring Agents / Q000737:chemistry; D053577:Interleukin-1 Receptor Accessory Protein / Q000276:immunology / Q000378:metabolism; D053583:Interleukin-1beta / Q000378:metabolism; D013058:Mass Spectrometry / Q000379:methods; D051379:Mice; D008958:Models, Molecular; D008969:Molecular Sequence Data; D058990:Molecular Targeted Therapy / Q000379:methods*; D010455:Peptides / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D011487:Protein Conformation; D054730:Protein Interaction Domains and Motifs; D025941:Protein Interaction Mapping / Q000379:methods*; D053573:Receptors, Interleukin-1 Type I / Q000378:metabolism; D012997:Solvents; D014357:Trypsin / Q000737:chemistry
chemical_list: D000911:Antibodies, Monoclonal; D004396:Coloring Agents; D053577:Interleukin-1 Receptor Accessory Protein; D053583:Interleukin-1beta; D010455:Peptides; D053573:Receptors, Interleukin-1 Type I; D012997:Solvents; D014357:Trypsin