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bioRxiv · 10.1101/2025.05.24.655972

Development of Second-Generation Acyl Silane Photoaffinity Probes for Cellular Chemoproteomic Profiling

Page, A. C. S.·Orr, L. M.·Meyers, M. L.·Belcher, B. P.·Coffey, T. G.·Scholz, S. O.·Cismoski, S.·Nomura, D.·Toste, F. D.
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Abstract

Deconvolution of the protein targets of hit compounds from phenotypic screens, often conducted in live cells, is critical for understanding mechanism of action and identifying potentially hazardous off-target interactions. While photoaffinity labeling and chemoproteomics are long-established approaches for discovering small-molecule-protein interactions in live cells, there are a relatively small number of photoaffinity labeling strategies that can be applied in intracellular settings. Recently, we reported a novel chemical framework for photoaffinity labeling based on the photo-Brook rearrangement of acyl silanes and demonstrated its ability, when appended to protein-targeting ligands, to label recombinant proteins. Here, we report the application of these probes to live cell photoaffinity workflows, demonstrate their complementarity to current state-of-the-art minimalist diazirine-based photoaffinity probes, and introduce a modular synthetic route to access acyl silane scaffolds with improved labeling properties.

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Page, A. C. S., Orr, L. M., Meyers, M. L., Belcher, B. P., Coffey, T. G., Scholz, S. O., Cismoski, S., Nomura, D., Toste, F. D.. 2025-05-28. Development of Second-Generation Acyl Silane Photoaffinity Probes for Cellular Chemoproteomic Profiling. https://doi.org/10.1101/2025.05.24.655972

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