TY - JOUR T1 - Photoactivation of silicon rhodamines via a light-induced protonation JF - bioRxiv DO - 10.1101/626853 SP - 626853 AU - Michelle S. Frei AU - Philipp Hoess AU - Marko Lampe AU - Bianca Nijmeijer AU - Moritz Kueblbeck AU - Jan Ellenberg AU - Jonas Ries AU - Stefan Pitsch AU - Luc Reymond AU - Kai Johnsson Y1 - 2019/01/01 UR - http://biorxiv.org/content/early/2019/05/04/626853.abstract N2 - We present a new type of photoactivatable fluorophore that forms a bright silicon rhodamine derivative through a light-dependent isomerization followed by protonation. In contrast to other photoactivatable fluorophores, no caging groups are required, nor are there any undesired side-products released. Using this photoactivatable fluorophore, we created probes for HaloTag and actin for live-cell single-molecule localization microscopy and single-particle tracking experiments. The unusual mechanism of photoactivation and the fluorophore’s outstanding spectroscopic properties make it a powerful tool for live-cell super-resolution microscopy. ER -