Monoarsenical-based chemical approaches for exploration of endogenous vicinal-dithiol-containing proteins (VDPs): From the design to their biological application

As one final end of the redox buffer network, endogenous protein vicinal thiols show a higher tendency to cope with redox changes and are more sensitive and prone to free-radical oxidation. Therefore, endogenous vicinal-dithiol-containing proteins (VDPs) are of considerable significance for regulating cellular functions through the reversible dithiols/disulfide inter-conversion reaction. However, compared to the critical role of VDPs, the detection approaches for exploration of the protein vicinal thiols and related VDPs are limited. Especially, no effective strategies had been used for in-situ detection of endogenous protein vicinal in live cells until that we discovered a fluorophore with dithiarsenolane to serve as a useful fluorescent probe for in-situ detection of VDPs in live cells. Thus, the idea of harnessing the power of chemical approaches to determine the protein vicinal dithiols and related VDPs has presented an optional tool for investigating the various functions of VDPs in the biological process and related diseases. In this review, we present different chemical probes-based strategies for the detection of endogenous protein vicinal thiols and related VDPs, especially focusing on the different monoarsenic-based fluorescent probes for real-time visualization of VDPs in live cells. The principle involved in the development of chemical strategies for tracing cellular endogenous VDPs, and problems and challenges in this field are also discussed. Finally, we prospect future research directions in this area.