Genetically encoded redox sensors

Endogenous redox sensors detect fluctuations in the intracellular redox equilibrium and are critical for the maintenance of homeostasis. Such systems have been exploited to engineer genetically encoded redox sensors to detect dynamic oxidative changes within a cellular environment. Most genetically encoded redox sensors detect reactive oxygen species (ROS) such as superoxide anion, hydrogen peroxide and hydroxyl radical. Technical hurdles including the limited temporal and spatial resolution as well as tissue heterogeneity have complicated the realization of the full potential of genetically encoded redox sensors in animals until recently. Alterations in the concentration and subcellular localization of ROS are integral to numerous disorders, including neurodegenerative diseases and cancer. Thus, genetically encoded redox sensors are useful for the study of the pathogenesis and progression of multiple diseases. Moreover, the ultimate generation of genetically encoded redox sensors provides substantial advantages over conventional methods such as ROS-sensitive fluorescent probes. Here, we review examples of genetically encoded redox sensors, present their application to various fields of biomedical investigation, including the study of oncometabolism, discuss their drawbacks and explore future developments.