Next Generation Protein Arylation Reagents

Researchers from the University of Kentucky are developing a new chemical strategy to control the motion of intrinsically disordered proteins, a large class of proteins that govern gene regulation, cell signaling, immune responses, and the progression of many human diseases. Unlike conventional proteins that fold into stable three-dimensional shapes, intrinsically disordered proteins remain flexible and constantly shifting, which leaves them largely invisible to existing small-molecule tools and has stalled progress in understanding fundamental biology and in creating new therapies. The research team will build a biotechnology platform that unites precise molecular recognition with selective gold-mediated covalent chemistry to bind and modulate these dynamic proteins inside living cells. Their discoveries could establish broadly useful methods for interrogating protein function, greatly expand the set of proteins that can be chemically controlled, and open new routes to studying biological regulation and disease mechanisms. The project will also provide interdisciplinary training in synthetic chemistry, chemical biology, proteomics, and molecular biology for high school, undergraduate, graduate, and postdoctoral researchers, and will support outreach that broadens participation in the chemical sciences. The project will establish a general framework for Metal-Mediated Ligand Affinity Chemistry (MLAC) to target intrinsically disordered proteins and intrinsically disordered regions through bioorthogonal gold-mediated arylation. The central hypothesis is that tunable gold(I) and gold(III) complexes with optimized Lewis acidity and reaction kinetics, paired with high-affinity molecular recognition ligands, will selectively form covalent carbon-sulfur or carbon-nitrogen bonds with nucleophilic cysteine and lysine residues, increasing target residence time and modulating protein function. The work will integrate synthetic organometallic chemistry, ligand design, quantitative chemical proteomics, intact-protein mass spectrometry, and cellular target-engagement assays to identify selective covalent reagents, define proteome-wide selectivity, and determine the functional consequences of engaging disordered proteins in living cells. The resulting molecular toolkit will expand the ligandable proteome, provide versatile reagents for protein labeling and functional interrogation, and establish broadly applicable principles for covalently targeting dynamic proteins that have remained inaccessible to conventional chemical approaches. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.