A "Double Click" for Illuminating Plant Cell Walls.

In this issue of Cell Chemical Biology, Lion et al. (2017) report a multiplexed labeling method to visualize plant cell wall lignification in vivo. This approach uses two different lignin precursor analogs tagged with azide and alkyne reporters that can be independently incorporated into cell walls, then differentially derivatized in vivo via two bioorthogonal click reactions: strain-promoted and copper-assisted azide-alkyne cycloadditions.