An in Vivo Mass Cytometry Probe for Protein Translation

Key words

mass cytometry - protein synthesis - tellurium - imaging mass cytometry

Significance

Protein translation is a dynamic process that is challenging to monitor in vivo; however, competitive incorporation of unnatural amino acids is one way to introduce a probe for detection. Imaging mass cytometry (IMC) is an imaging technique that follows a similar workflow as immuno­fluorescence imaging. It uses a mass-tag instead of a fluorescent dye for detection and does not require post-translational modification. The geometric properties of tellurophene make the unnatural amino acid TePhe an excellent isostere of phenylalanine.

Comment

TePhe is a non-toxic small-molecule probe that can be used to measure and visualize protein translation both in vitro and in vivo. Exploiting the native translation machinery, TePhe is competitively incorporated into proteins without the need for phenylalanine starvation. Using IMC, protein synthesis in mice (gut, brain and tumor) was monitored with spatiotemporal precision. Tellurium isotope enrichment enables multi-channel observations. Additionally, this tellurium-containing probe has also high potential for use in NMR spectroscopy or X-ray crystallography.