Photocrosslinking of DNA using 4-methylpyranocarbazole nucleoside with thymine base selectivity

A light-initiated chemical reporter strategy for spatiotemporal labeling of biomolecules

The emergence of optochemical approaches has had a diverse impact over a broad range of biological research due to spatiotemporal regulation. Herein, we integrate this feature into the bioorthogonal chemical reporter strategy, which enables visible light-controlled spatiotemporal labeling of cell-surface glycans, lipids, and proteins. The metabolic precursors were first incorporated into live cells, and next the bioorthogonal reaction converted the azide/alkyne into a photo-active functional group, which allowed for subsequent photo-click reaction. We demonstrated this strategy by specifically labeling sialome, mucin-type O-glycome, phospholipids and newly-synthesized membrane proteins, respectively. The sequential photoirradiation-orthogonal reporter tagging (SPORT) should facilitate the probing of biomolecules in complex biological systems with high spatiotemporal precision.