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Updated: Oct 3, 2026

Identification of Small Molecule-binding Proteins in a Native Cellular Environment by Live-cell Photoaffinity Labeling
Published on: September 20, 2016
Mechanisms and Applications of Photocatalytic Proximity Labeling
Enze Gong1,2,3,4,5, Yalan Xie6, Wei Qin1,2,3,4,5
1The State Key Laboratory of Membrane Biology, Tsinghua University, Beijing 100084, China.
Abstract:
Photocatalytic proximity labeling (PPL) is a light-controlled technique for spatially and temporally precise mapping of biomolecular interactions. This review classifies PPL platforms into small-molecule catalysts (transition metal complexes and organic chromophores) and genetically encoded photosensitizers, detailing their mechanisms and biological applicationsfrom subcellular proteomics, cell-cell interface tagging to in vivo labeling. We compare PPL with enzyme-catalyzed methods, highlighting its advantages in spatiotemporal control, minimal genetic manipulation, and suitability for primary cells. Current challenges in PPL are also discussed. As PPL methodologies continue to evolve from mechanistic innovation toward essential biological problem-solving, they hold great promise for elucidating dynamic interaction networks with unprecedented resolution in living systems.
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