Inhibition of Protein Synthesis with Highly Soluble Caged Compounds

To target protein synthesis in defined areas, e.g. neuropiles of small brains or subcellular structures, locally restricted inhibition of protein synthesis is needed and can be realized by caged compounds of protein synthesis inhibitors (PSI). Since organic solvents interfere with protein synthesis themselves, the use of water-soluble caged PSIs is a prerequisite in studies on protein synthesis. Such compounds are sparsely available. We developed and characterized efficient highly soluble caged compounds of the PSIs anisomycin and emetine masking their biological activity with a {8-[bis(carboxymethyl)aminomethyl]-6-bromo-7-hydroxycoumarin-4-yl}methoxycarbonyl (BBHCMOC) derivative. The absorption spectra of the resulting BBHCMOC-caged anisomycin and BBHCMOC-caged emetine show long-wavelength maxima and the extinction coefficients are high, allowing uncaging under non-damaging light conditions. When uncaged, these caged PSIs reliably inhibit protein synthesis in an in vitro translation system and in cell culture. Taken the whole spectrum of properties into account, our BBHCMOC-caged PSIs are highly qualified for in vivo studies.