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bioRxiv · 10.64898/2026.08.05.742576

μMap-uAA: Photocatalytic proximity labeling targeted with single-residue precision

Kang, M. S.·Li, C.·Buksh, B. F.·Fernandez, D.·MacMillan, D. W. C.
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Abstract

Mapping protein microenvironments with residue-level precision in living cells remains challenging. We report Map-uAA, a genetically encoded proximity labeling platform that uses unnatural amino acid incorporation to install a tetrazine-quenched iridium photocatalyst at user-defined protein sites through click chemistry. Photocatalysis is activated by covalent attachment to the incorporated uAA, enabling localized catalytic labeling of proximal biomolecules. Applied to membrane receptors, Map-uAA captures domain- and time-dependent GPCR interaction networks with residue-level spatial precision.

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Kang, M. S., Li, C., Buksh, B. F., Fernandez, D., MacMillan, D. W. C.. 2026-08-06. μMap-uAA: Photocatalytic proximity labeling targeted with single-residue precision. https://doi.org/10.64898/2026.08.05.742576

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