Migration from Lysosome to Nucleus: Monitoring Lysosomal Alkalization-Related Biological Processes with an Aminofluorene-Based Probe

Abstract

Aberrant lysosomal alkalization is associated with various biological processes, such as oxidative stress, cell apoptosis, ferroptosis, etc. Herein, we developed a novel aminofluorene-based fluorescence probe named <b>FAN</b> to monitor the lysosomal alkalization-related biological processes by its migration from lysosome to nucleus. <b>FAN</b> possessed NIR emission, large Stokes shift, high pH stability, and high photostability, making it suitable for real-time and long-term bioimaging. As a lysosomotropic molecule, <b>FAN</b> can accumulate in lysosomes first and then migrate to the nucleus by right of its binding capability to DNA after lysosomal alkalization. In this manner, <b>FAN</b> was successfully used to monitor these physiological processes which triggered lysosomal alkalization in living cells, including oxidative stress, cell apoptosis, and ferroptosis. More importantly, at higher concentrations, <b>FAN</b> could also serve as a stable nucleus dye for the fluorescence imaging of the nucleus in living cells and tissues. This novel multifunctional fluorescence probe shows great promise for application in lysosomal alkalization-related visual research and nucleus imaging.