Imaging Intracellular H 2 O 2 with the Genetically Encoded PerFRET and OxyFRET Probes.

Hydrogen peroxide (HO) is an important signaling intermediate with various regulatory and effector functions. Despite its significance, the subcellular organization of HO signals is poorly understood. Introducing novel techniques for the intracellular detection of HO would be essential for a more complete understanding of its role in cellular signaling. We previously reported the development of two novel fluorescence resonance energy transfer (FRET)-based protein sensors that showed opposite emission ratio changes upon reaction with HO. In this chapter, we detail the methods for using OxyFRET and PerFRET for the assessment of changes in subcellular HO levels.