Development of a Golgi-targeted fluorescent chemosensor for detecting ferrous ions overload under Golgi stress

Ferrous ion (Fe2+) is a crucial metal ion in the body and participates in the diseases related to oxidation and reduction. Golgi apparatus is the main subcellular organelle of Fe2+ transport in cells, and the stability of its structure is related to the Fe2+ at an appropriate concentration. In this work, a turn-on type Golgi-targeting fluorescent chemosensor Gol-Cou-Fe2+ was rationally designed for sensitive and selective detection of Fe2+. Gol-Cou-Fe2+ showed excellent capacity of detecting exogenous and endogenous Fe2+ in HUVEC and HepG2 cells. It was used to capture the up-regulated Fe2+ level during the hypoxia. Moreover, the fluorescence of sensor was enhanced over time under Golgi stress combining with the reduce of Golgi matrix protein GM130. However, elimination of Fe2+ or addition of nitric oxide (NO) would restore the fluorescence intensity of Gol-Cou-Fe2+ and the expression of GM130 in HUVEC. Thus, development of chemosensor Gol-Cou-Fe2+ provides a new window for tracking Golgi Fe2+ and elucidating Golgi stress-related diseases.